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高粱壳制色素
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《林业与社会》 1997年第3期10-10,共1页
利用红高粱壳生产天然红色素其成本只有用红辣椒生产红色素的1/4,且工艺简单,产品提取率可达6%左右。产品果颗粒状,粒度小于100目。
关键词 高粱壳 天然红 制色 提取率 红辣椒 理化指标 安全性能 脱贫致富 保健品
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中国礼制建筑的色彩伦理探析 被引量:1
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作者 王萍 《流行色》 2020年第8期50-53,共4页
礼制是中国传统文化的核心,中国古代建筑是中华文化及意识形态的载体。在中国古建筑中能体现宗法礼制的建筑都称为礼制建筑,以祭祀性建筑最为典型。对礼制建筑的探索十分有价值,不仅能从建筑中总结我国传统文化的独特性,还能梳理中国传... 礼制是中国传统文化的核心,中国古代建筑是中华文化及意识形态的载体。在中国古建筑中能体现宗法礼制的建筑都称为礼制建筑,以祭祀性建筑最为典型。对礼制建筑的探索十分有价值,不仅能从建筑中总结我国传统文化的独特性,还能梳理中国传统建筑的设计特点,尤其是色彩在伦理意识形态下的应用特点,这对东方美学意识下的色彩实践,对美丽乡村、美丽城镇的色彩营造都有积极意义。本文侧重中国礼制建筑在敷色过程中的色相选择,并探究其背后的伦理缘由。 展开更多
关键词 中国礼建筑 彩伦理
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多色纹制工艺自动化中分色原理的研究
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作者 蔡乃琛 《丝绸》 CAS 北大核心 1989年第12期17-20,共4页
由于电子计算机处理纺织图样信息的过程中要求数值化,所以在分解色彩时,首先是由光电扫描器正确地取得图样上象素的R、G、B信息;其次是必须建立适合于电子线路判别色彩的分色模型,求得各种色彩的数值表示。文章从色度学的角度提出了更... 由于电子计算机处理纺织图样信息的过程中要求数值化,所以在分解色彩时,首先是由光电扫描器正确地取得图样上象素的R、G、B信息;其次是必须建立适合于电子线路判别色彩的分色模型,求得各种色彩的数值表示。文章从色度学的角度提出了更合理的分色模型和相应的数学关系。 展开更多
关键词 模型 纺织图样
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安全帽实名制管理 被引量:1
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作者 陈必文 罗洪明 何文 《企业管理》 北大核心 2014年第7期92-94,共3页
对企业管理者来说,管理方法越简单越适用越好。罗洪明项目部的安全帽实名制管理,虽是小革新,但解决了实际问题,也引起了管理者对安全管控的重新思考。
关键词 安全帽 实名 安全管控 四川电力
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彩色图象的反扩散恢复
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作者 林瑛 蔡利栋 《暨南大学学报(自然科学与医学版)》 CAS CSCD 1999年第5期37-44,共8页
讨论由扩散引起模糊的彩色图象恢复问题结果表明即使扩散系数的选取是适当的,由于 R G B 彩色空间的非线性,直接对彩色图象的 R G B 三色进行反扩散恢复仍是不合理的为此考虑了其它几种不同的彩色表示法,分析比较了它们对... 讨论由扩散引起模糊的彩色图象恢复问题结果表明即使扩散系数的选取是适当的,由于 R G B 彩色空间的非线性,直接对彩色图象的 R G B 三色进行反扩散恢复仍是不合理的为此考虑了其它几种不同的彩色表示法,分析比较了它们对彩色图象反扩散恢复的影响,并介绍了一种新颖的颜色空间——— I Z 展开更多
关键词 图像 反扩散恢复 扩散系数 HSV RGB
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制造企业节电增效的技术与管理协同推进机制 被引量:1
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作者 梁祖坤 易小明 《上海节能》 2023年第12期1788-1798,共11页
电力等能源消耗是制造企业的主要成本构成因素之一,节电降耗对于企业的利润改善和社会效益提升有重要作用。文献分析发现,制造企业的节电降耗主要分成技术创新和管理改善两个方面,相关的研究与实践也集中于这两条路径,但对于如何发挥这... 电力等能源消耗是制造企业的主要成本构成因素之一,节电降耗对于企业的利润改善和社会效益提升有重要作用。文献分析发现,制造企业的节电降耗主要分成技术创新和管理改善两个方面,相关的研究与实践也集中于这两条路径,但对于如何发挥这两条路径的协同作用及建立综合推进机制却未见有充分的研究。通过分析节能降耗的机会和所需的支持资源,总结出技术性和管理性节电增效推进力量的共性部分,并归纳出制造企业节电增效的技术与管理协同推进机制模型,然后依据该模型对4家案例企业的节电管理工作进行了实证分析并找出问题。该模型对于制造企业的节能降耗具有较好的指导意义。 展开更多
关键词 节电 技术创新 管理架构 协同推进机
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离子色谱法测定蚀刻槽废氢氟酸中的六氟硅酸 被引量:4
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作者 霍世欣 罗全迁 曹琳 《色谱》 CAS CSCD 北大核心 2016年第10期982-985,共4页
建立了一种新的检测蚀刻槽废氢氟酸中六氟硅酸的离子色谱方法.色谱柱为Metrosep A Supp 7 阴离子交 换柱,流动相为3. 2 mmol/L 碳酸钠-1. 0 mmol/L 碳酸氢钠,流速为0. 7 mL/min.六氟桂酸经过抑制型电导检测 器后进行衍生化反应,在360 n... 建立了一种新的检测蚀刻槽废氢氟酸中六氟硅酸的离子色谱方法.色谱柱为Metrosep A Supp 7 阴离子交 换柱,流动相为3. 2 mmol/L 碳酸钠-1. 0 mmol/L 碳酸氢钠,流速为0. 7 mL/min.六氟桂酸经过抑制型电导检测 器后进行衍生化反应,在360 nm波长下用紫外检测器检测.六氟硅酸的线性范围为2. 4- 120 mg/L ,相关系数r 2 大于0. 999,定量限为0. 24 mg/L ,平均加标回收率为97. 2%.本方法还可以同时利用电导检测器检测废氢氟酸中 的氢氟酸、醋酸、盐酸、硝酸、磷酸和硫酸的含量.该方法快速、准确,适用于蚀刻槽液中六氟硅酸的检测. 展开更多
关键词 离子 紫外检测器 电导检测器 六氟硅酸
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严把“进口”畅通“出口”完善党员发展教育管理制度的探索
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作者 赵连城 《大观周刊》 2012年第34期15-16,42,共3页
农村党员发展“进口把关不严”、党员队伍“质量不优”、不合格党员“出口不畅”的问题令人困惑。浙江省新昌县建立以“三分四步法”为主要内容的党员教育管理制度体系,形成了农村党员“进出口”通道的初步模式,构建了农村党员发展教... 农村党员发展“进口把关不严”、党员队伍“质量不优”、不合格党员“出口不畅”的问题令人困惑。浙江省新昌县建立以“三分四步法”为主要内容的党员教育管理制度体系,形成了农村党员“进出口”通道的初步模式,构建了农村党员发展教育管理的长效机制。 展开更多
关键词 农村党员管理 “进出口”通道 预警 公层亮分 分步退出
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链霉菌702抗尖孢镰刀菌次级代谢产物的分离鉴定及活性研究 被引量:3
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作者 魏赛金 张智平 +2 位作者 涂晓嵘 何健 涂国全 《江西农业大学学报》 CAS CSCD 北大核心 2011年第5期982-986,共5页
从链霉菌702代谢产物中分离纯化抗尖孢镰刀菌的活性成分。以抗尖孢镰刀菌活性为导向,采用多种色谱分离技术对活性成分进行分离纯化,并对其理化性质和波谱学数据进行测定和综合解析,鉴定其化学结构。结果从链霉菌702代谢产物中分离得到1... 从链霉菌702代谢产物中分离纯化抗尖孢镰刀菌的活性成分。以抗尖孢镰刀菌活性为导向,采用多种色谱分离技术对活性成分进行分离纯化,并对其理化性质和波谱学数据进行测定和综合解析,鉴定其化学结构。结果从链霉菌702代谢产物中分离得到1个多烯大环内酯化合物,经鉴定为制霉色基素(Fungichromin),该化合物具有显著的抗尖孢镰刀菌作用,其尖孢镰刀菌古巴"专化型"FOC1、FOC4的EC50和EC90分别为4.7、3.4μg/mL和21.5、53.1μg/mL。 展开更多
关键词 链霉菌702 抗尖孢镰刀菌古巴“专化型”活性 次生代谢产物 基素
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两种新型多烯大环内酯抗生素对四种水稻病原真菌的抗菌活性和毒力测定 被引量:3
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作者 芦慧 魏赛金 +2 位作者 涂晓嵘 徐佳 涂国全 《湖北农业科学》 北大核心 2012年第6期1123-1127,共5页
离体条件下,采用菌丝生长速率法和菌丝干重法测定新型多烯大环内酯抗生素——抗真菌霉素702和制霉色基素对水稻纹枯病菌(Rhizoctonia solani)、水稻菌核病菌(Helminthosporium sigmoideum Cav.)、稻瘟病菌(Magnaporthe grisea)、稻曲病... 离体条件下,采用菌丝生长速率法和菌丝干重法测定新型多烯大环内酯抗生素——抗真菌霉素702和制霉色基素对水稻纹枯病菌(Rhizoctonia solani)、水稻菌核病菌(Helminthosporium sigmoideum Cav.)、稻瘟病菌(Magnaporthe grisea)、稻曲病菌(Ustilaginoidea virens)4种水稻病原真菌的抗菌活性和毒力。结果表明,抗真菌霉素702和制霉色基素对4种水稻病原真菌具有较强的抗菌活性,50μg/mL抗真菌霉素702对水稻纹枯病菌、水稻菌核病菌、稻瘟病菌和稻曲病菌的抑菌率分别为100.00%、100.00%、91.72%和68.06%,EC50分别为7.00、10.30、14.41、26.71μg/mL,EC90分别为13.20、17.66、27.67、128.28μg/mL。13μg/mL制霉色基素对水稻纹枯病菌、水稻菌核病菌、稻瘟病菌和稻曲病菌的抑菌率分别为78.20%、100.00%、100.00%和79.17%,EC50分别为1.47、1.91、2.37、0.20μg/mL,EC90分别为41.05、3.92、4.34、135.54μg/mL。总体上,制霉色基素对4种水稻病原真菌的抑菌活性强于抗真菌霉素702。 展开更多
关键词 链霉菌702 抗真菌霉素702 基素 抗菌活性 水稻病原真菌
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A New Role Hierarchy Model for Role Based Access Control 被引量:2
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作者 吕宜洪 宋瀚涛 龚元明 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期409-413,共5页
A new role hierarchy model for RBAC (role-based access control) is presented and its features are illustrated through examples. Some new concepts such as private permission, public permission and special permission ar... A new role hierarchy model for RBAC (role-based access control) is presented and its features are illustrated through examples. Some new concepts such as private permission, public permission and special permission are introduced, based on the RRA97 model. Some new role-role inheriting forms such as normal inheritance, private inheritance, public inheritance and special-without inheritance are defined. Based on the ideas mentioned, the new role hierarchy model is formulated. It is easier and more comprehensible to describe role-role relationships through the new model than through the traditional ones. The new model is closer to the real world and its mechanism is more powerful. Particularly it is more suitable when used in large-scale role hierarchies. 展开更多
关键词 RBAC access control ROLE INHERIT role hierarchy
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Multimodal background model with noise and shadow suppression for moving object detection 被引量:1
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作者 毛燕芬 施鹏飞 《Journal of Southeast University(English Edition)》 EI CAS 2004年第4期423-426,共4页
A statistical multimodal background model was described for moving object detection in video surveillance. The solution to some of the problems such as illumination changes, initialization of model with moving objects... A statistical multimodal background model was described for moving object detection in video surveillance. The solution to some of the problems such as illumination changes, initialization of model with moving objects, and shadows suppression was provided. The background samples were chosen by thresholding inter-frame differences, and the Gaussian kernel density estimation was used to estimate the probability density function of background intensity. Pixel's neighbor information was considered to remove noise due to camera jitter and small motion in the scene. The hue-max-min-diff color information was used to detect and suppress moving cast shadows. The effectiveness of the proposed method in the foreground segmentation was demonstrated in the traffic surveillance application. 展开更多
关键词 Gaussian noise (electronic) Image segmentation Space surveillance Tracking (position) Traffic control Video cameras
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Attribute-based access control policy specification language 被引量:6
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作者 叶春晓 钟将 冯永 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期260-263,共4页
This paper first introduces attribute expression to describe attribute-based access control policy.Secondly,an access control policy enforcement language named A-XACML (attribute-XACML)is proposed,which is an extens... This paper first introduces attribute expression to describe attribute-based access control policy.Secondly,an access control policy enforcement language named A-XACML (attribute-XACML)is proposed,which is an extension of XACML.A-XACML is used as a simple,flexible way to express and enforce access control policies,especially attribute-based access control policy,in a variety of environments.The language and schema support include data types,functions,and combining logic which allow simple and complex policies to be defined.Finally,a system architecture and application case of user-role assignment is given to show how attribute expressions and A-XACML work in access control policy description and enforcement.The case shows that attribute expression and A-XACML can describe and enforce the complex access control policy in a simple and flexible way. 展开更多
关键词 role-based access control POLICY XML XACML
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Novel scheme to specify and integrate RBAC policy based on ontology 被引量:1
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作者 孙小林 卢正鼎 +2 位作者 李瑞轩 王治刚 文坤梅 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期394-398,共5页
To describe and integrate various policies applied in different domains, the definition of the family of OntoRBAC based on the ontology of a general role-based access control (RBAC) policy is proposed, which can sup... To describe and integrate various policies applied in different domains, the definition of the family of OntoRBAC based on the ontology of a general role-based access control (RBAC) policy is proposed, which can support and extend the RBAC96 model. The uniform ontology-based description mechanism of secure policies is applied in OntoRBAC, which can be used to describe different secure policies in distributed systems and integrate policies in semantic level with upper concepts. In addition, some rules have been defined to reason within the OntoRBAC to extend the inference algorithms in ontology, which makes the system accommodate itself to RBAC policies better. 展开更多
关键词 ONTOLOGY POLICY role-based access control
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Plasma methods for preparing green catalysts: Current status and perspective 被引量:8
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作者 刘昌俊 李敏悦 +4 位作者 王嘉琪 周昕瞳 郭秋婷 严金茂 李英芝 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第3期340-348,共9页
Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catal... Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks (MOFs), covalent organic framework(COFs), high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water(or solution) surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed. 展开更多
关键词 Catalyst preparation PLASMA Green chemistry Porous material
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Research Progress on Mechanized Mixed Sowing Seed Production Technology of Hybrid Rice 被引量:4
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作者 张德文 《Agricultural Science & Technology》 CAS 2017年第5期924-929,939,共7页
Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The resea... Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The research progress on mixed sowing seed production techniques of hybrid rice was introduced from the aspects of rice resources creation, breeding, sowing seed technology research and cost benefit analysis. The production technology of the new mixed seeding combina- tion "Xinhunyou 6" was investigated, including the research and validation of benta- zon treatment period and dosage, mixing ratio of male and female parents, and the comparative test of different different sowing methods, which revealed that the mechanization technology of seed production of hybrid rice was mature and feasible and would be one of the most important development trend of technological devel- opment of hybrid rice production. 展开更多
关键词 Hybrid rice Mechanized seed production Glume color marker gene BENTAZON Research progress
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Effect of Quercetin on CYP1A2, CYP2E1, CYP3A2 Activities and its Inhibitory Mechanism Studies in Rat Liver Microsomes 被引量:6
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作者 周江泉 汤致强 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期231-236,共6页
Aim To assess the potential effect of quercetin (QU), an natural plant estrogen, on CYP1A2, CYP2E1, and CYP3A2 activities in rat liver microsomes; and to identify the magnitude of inhibitory effect and the probable ... Aim To assess the potential effect of quercetin (QU), an natural plant estrogen, on CYP1A2, CYP2E1, and CYP3A2 activities in rat liver microsomes; and to identify the magnitude of inhibitory effect and the probable inhibitory mechanism of QU. Methods QU and specific substrate were concurrently incubated, with HPLC detection of the substrate metabolites for data analysis. The magnitude of inhibitory effect of QU on CYP3A2 was compared with those of ketoconazole (Ket) and erythromycin (Ery). The mechanism of its inhibitory effect on CYP3A2 and CYP2E1 was derived from Lineweaver-Burk plots. Results HPLC methods were in good linear relationship with r〉0.999 1. Relative standard deviations for intra-day and inter-day were〈8.4%. Recovery of each analyte in the concentrations studied was between 91.1% and 107.6 %. QU (up to 8 μmol·L^-1) showed potent induction to CYP1A2 (338.1% of the negative control)while inhibited CYP2E1 (49.2% of the negative control) and CYP3A2 (60.3% of the negative control) activity. The magnitude of inhibitory effect for QU on CYP3A2 was between those for Ket and Ery (Ket〉QU〉Ery). QU exhibited competitive inhibition of CYP3A2 dextromethorphan N-demethylation reaction and expressed noncompetitive inhibition of CYP2E1 chlorzoxazone-6-hydroxylation reaction. Conclusion HPLC assay has been validated with precision and accuracy. QU is an effective inhibitor of several CYP isoforms. It may cause relevant drug-drug interactions with CYP3A substrates. As a plant flavonoid, QU has potential not only in molecular advantage but also in CYP450 module capability for further application in cancer chemotherapy. 展开更多
关键词 QUERCETIN cytochrome P450 liver microsome HPLC INHIBITOR
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Segmental Duplications Are Common in Rice Genome 被引量:1
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作者 王石平 刘克德 张启发 《Acta Botanica Sinica》 CSCD 2000年第11期1150-1155,共6页
Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hyb... Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hybridization bands detected by a repetitive sequence probe, rTRS, were mapped to the ends of all the four chromosomes. Two or three of the bands detected by each of the other 12 probes were also mapped to different chromosomes. The bands detected by the same probe usually occurred in similar locations of different chromosomes. Loci detected by different DNA probes were often similarly arranged on different chromosomes. Chromosomes 8 and 9 showed colinearity of marker loci arrangement indicating a possible common origin. A segment on chromosome 9 was also very similar to the previously reported duplicated fragments on the ends of chromosomes 11 and 12 which were also detected in this study, indicating a likely common origin. Moreover, the various degrees of distributional similarity of the segments suggest a complex relationship among the chromosomes in the evolution of the rice genome. These results support the proposition that chromosome duplication and diversification may be a mechanism for the origin and evolution of the chromosomes in the rice genome. 展开更多
关键词 chromosomal duplication repetitive sequence molecular mapping EVOLUTION r€
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Determination of Eleutheroside B and E in Acanthopanax Preparations by High-P erformance Liquid Chromatography with Solid-Phase Extraction 被引量:6
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作者 胡芳弟 封士兰 +2 位作者 赵健雄 陈立仁 徐静汶 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第1期51-55,共5页
Aim An HPLC method for analyzing eleutheroside B (ELU B) and eleutheroside E(ELU E) , two of the main active substances of Acanthopanax preparations were studied. Methods Thesamples were analyzed on a kromasil ODS col... Aim An HPLC method for analyzing eleutheroside B (ELU B) and eleutheroside E(ELU E) , two of the main active substances of Acanthopanax preparations were studied. Methods Thesamples were analyzed on a kromasil ODS column with water-acetonitrile as a gradient mobile phase.The flow rate was 0.8 mL·min^(-1) and detecting wavelengths were 206 nm for ELU B, 220 nm for ELUE, solid phase extraction (SPE) and internal standard-salicin were selected. Results The recoveriesof Acanthopanax tablets and injection were 90.4% - 96.8% and 96.4% - 99.8% for ELU B, 87.7% -93.3%and 95.7% - 98.5% for ELU E, respectively. The linear ranges were 4.45 - 22.25 μg· mL^(-1) (r =0.999 8) and 5.11 - 25.55 μg·mL^(-1) ( r = 0.999 7) respectively. Conclusion This method can savethe time for cleaning the chromatographic system and improve sensitivity for Acanthopanaxpreparations , thus providing a way to evaluate the quality of Acanthopanax preparations. 展开更多
关键词 eleutherosides acanthopanax preparations HPLC solid phase extraction
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Simultaneous Determination of Tetramethylpyrazine and Aspirin in a New Compound Formulation by Liquid Chromatography 被引量:2
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作者 王鹏 齐美玲 +1 位作者 周莉 方林 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期58-62,共5页
Aim To establish a reversed-phase liquid chromatographic (LC) method forsimultaneous determination of tetramethylpyrazine (TMP) and aspirin in a new compound formulation.Methods Chromatographic separation of the two d... Aim To establish a reversed-phase liquid chromatographic (LC) method forsimultaneous determination of tetramethylpyrazine (TMP) and aspirin in a new compound formulation.Methods Chromatographic separation of the two drugs was achieved on a Diamonsil C_(18) column, usinga binary mixture of methanol-1.5% acetic acid (35:65, V/V, pH = 3.1) as mobile phase at a flow rateof 1.0 mL·min^(-1). Results Separation was completed in less than 12 min. Benzoic acid was used asthe internal standard. Recoveries at levels corresponding to 80 % to 120 % of the label claim ofthe formulation ranged from 99.6 to 100.3 % for aspirin and from 99.9 to 101.3% for TMP. The linearrange was 12.6 - 150.9 μg·mL^(-1)(r= 0.9997, n = 5) for aspirin and 25.0- 300.0 μg·mL^(-1) (r =0.9999, n = 5) for TMP. Conclusion The method developed can be used for the simultaneousdetermination of TMP and aspirin in pharmaceutical preparations. 展开更多
关键词 liquid chromatography TETRAMETHYLPYRAZINE ASPIRIN ASSAY
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