首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
建立了同时测定氧化槐果碱、槐定碱和苦参碱的HPLC(高效液相色谱)方法.用VP-ODS(维普C18柱)150mm × 4.6 mm, 5 μm 色谱柱,柱温40 ℃,流动相为0.01mol/L pH 8.5磷酸盐缓冲溶液-甲醇(40 ∶60),流速 1.0 mL/min,紫外检测器波长215 nm.结果表明,3种生物碱在确定的色谱条件下得到很好的分离,且在所选质量浓度范围20~200 mg/L 内线性关系良好,回收率范围97.2%~102%.  相似文献   

2.
建立一种快速、简单、有效的胶束电动色谱技术分别检测猪饲料、猪肝、猪肉和猪尿中的5种β2受体兴奋剂.获得优化后的分离缓冲液为15 mmol/L SDS、15 mmol/L硼酸钠、p H=10、以及毛细管温度为25℃.在优化条件下,5种β2受体兴奋剂在18 min内完成分离,在0.1~40μg/m L浓度范围内具有良好的线性关系(R20.999),其检出限(S/N≥3)在0.05~0.08μg/m L范围之间.西马特罗,莱克多巴胺,克伦特罗具有较好的回收率(n=3),分别为95.8%,93.1%,95.0%;而沙丁胺醇和特布他林的回收率较低,分别为52.3%和69.4%.被测物的峰面积和迁移时间的相对标准偏差分别小于4.86%和1.25%.利用该方法对5种不同猪饲料、猪肝、猪肉和猪尿样品中的沙丁胺醇,特布他林,西马特罗,莱克多巴胺和克伦特罗进行了筛查.  相似文献   

3.
高效液相色谱法测定大蒜中吡虫啉残留   总被引:2,自引:0,他引:2  
建立了大蒜中吡虫啉残留分析的高效液相-二极管阵列检测方法。样品经甲醇提取浓缩后,用5%氯化钠水溶液及石油醚萃取,再用二氯甲烷反萃取水相,吹干,定容,采用反向C 18色谱柱,流动相为甲醇/水(体积比32:68),波长为272nm。结果表明:在0.1~10.0μg/mL范围内回归方程为:Y=126.208X-1.348,相关系数为0.99998,呈良好的线性关系,方法检出限为0.05m g/kg,平均回收率为79.6%~88.2%,相对标准偏差为2.1%~3.2%。  相似文献   

4.
研究了用ALLIANCE自动分析仪测定烟草中的果胶的方法.样品经80%乙醇回流抽提后,在55~60℃和pH为4.0的磷酸盐缓冲溶液中用果胶酶酶解,用流动分析仪测定酶解液中的果胶含量.与传统的重量法相比,该法的回收率为97~104%,RSD为0.58~1.07%,且操作简便快速,准确度高,精密度好,便于批量样品的处理,为准确、快速地测定烟草中的果胶提供了一种便利的方法.  相似文献   

5.
研究了用微波消解矿石样品中的金,并用火焰原子吸收分光光度法对其进行测定的方法.结果表明,金含量在0~3.5μg/mL范围内符合比耳定律,方法相对标准偏差在2.5%~3.2%之间,标准回收率在89%~104%之间,其结果令人满意.  相似文献   

6.
研究了用3,5-二溴-2-吡啶偶氮重氮氨基偶氮苯(3,5-DB-PDAB)固相萃取光度法测定镉,在pH=10的硼砂-氢氧化钠缓冲介质中,TritonX-100存在下,3,5-DB-PDAB与镉反应生成2:1稳定络合物,体系最大吸收波长为528nm,摩尔吸光系数ε=1.65×105L.mol-1.cm-1,样品中的镉用强阴离子交换固相萃取柱固相萃取预分离和富集后用该方法测定,结果令人满意.  相似文献   

7.
目的 建立测定清肺排毒汤中盐酸麻黄碱、盐酸伪麻黄碱、甘草苷、苦杏仁苷、甘草酸、黄芩苷和黄芩素含量的高效液相色谱(HPLC)法。方法 采用Venusil MP-C18色谱柱(4.6 mm×250 mm,5μm);柱温:25℃;流速:1.0 mL·min-1;检测波长:210 nm;流动相:A:0.1%磷酸,B:乙腈,梯度洗脱。结果 在各成分浓度范围内,浓度与峰面积呈良好线性关系,相关系数r在0.999 3~0.999 9之间,平均回收率99.21%~102.66%,RSD0.63%~1.88%(n=9),该方法的精密度、重复性及稳定性的RSD均小于2.0%。结论 本方法可用于清肺排毒汤中盐酸麻黄碱、盐酸伪麻黄碱、甘草苷、苦杏仁苷、甘草酸、黄芩苷和黄芩素的含量测定。  相似文献   

8.
目的:建立西洋参药材根中12种农药残留的分离测定方法.方法:采用气相色谱法,HP-608弹性石英毛细管柱,ECD检测器,柱温起始温度150℃,以5℃/min速度升温,至230℃,保温5min;进样器温度240℃,检测器温度250℃,载气为高纯氮,柱流速20mL/min,层吹流速40mL/min,用外标法计算农药残留的含量.结果:12种农药的峰面积和质量浓度(mg/L)在测定范围内均具有良好的线性关系,精密度良好,平均回收率为94.1%~99.4%.结论:所用方法简单准确,灵敏度高,适用于西洋参药材根中12种农药残留含量的同时测定.  相似文献   

9.
建立党参中18种农药残留量的分析方法,对10种不同批次的党参样品进行农药残留测定。样品以乙腈-水(5+1)涡旋震荡萃取,提取液经Carb/NH2固相萃取柱(SPE)净化后、再经在线凝胶渗透色谱(gel permeation chromatography,GPC)净化,利用气相色谱-质谱选择离子监测模式进行分析,外标法定量。18种农药峰面积与质量浓度在10~1000μg·L-1呈良好线性关系,相关系数为0.993~1.000;定量限(10S/N)在0.06~6.3μg·kg-1;在20~200μg·kg-13个浓度水平下,方法回收率为76.8%-104.4%,RSD为4.2%~9.9%。该方法简便、快速,灵敏度高、重复性好,能够准确地检测党参中18种农药残留。  相似文献   

10.
研究了8-羟基喹哪啶与铁的显色反应,在pH为8.0的氯化氨-氨水缓冲介质中,在乳化剂-OP存在下,8-羟基喹哪啶与铁反应生成3∶1的稳定的蓝紫色络合物.该络合物可被W aters Plus-C18固相萃取小柱萃取富集,富集的络合物用乙醇为洗脱剂洗脱后用光度法测定.在乙醇介质中,络合物最大吸收波长λmax=595 nm,ε=7.82×103L.mol-1.cm-1.铁含量在0.1~5.0μg/mL内符合比尔定律,方法用于生物样品中痕量铁的测定,结果令人满意.  相似文献   

11.
The article introduces Shakespeare's tragedy "Hamlet".Hamlet wants to revenge for his father.But when the opportunity is coming,he delays his revenge.The passage analyzes the causes of his delay from Hamlet's characters.  相似文献   

12.
Since the late 1960s,culture has been considered tighter with communication.Culture IS based on the community of communication.Communication involves people and their environment.Thus culture is an important factor in communication.Today with modem economic and technological development,intercultural communication is mole important than ever before. When people from different cultural background communicate with each other,their social stereotype pattern of behavior, their habits of language and thought differ from one another,because these are the possible factors that affect intercultural communications.Culture norms also change,culture may be transferred as signs but we have to study and understand the above carefially.  相似文献   

13.
The thesis mainly discusses the character of the heroine in Charlotte Brontes famous novel "Jane Eyre". There are three major parts-introduction,analysis which is the main body of the thesis,and conclusion.Jane Eyre,the heroine,is a new woman image who requires independence equality and freedom.The thesis just analyzes Janes these rebellious characters through four peroods of her experiences.First,in her childhood,she has shown her rebellious spirit.As an orphan,Jane suffers a lot of misery.Not only her aunt treats her cruelly,her cousins despise her,but also do servants have a prejudice against her.In Janes immature heart, she is unwilling to bear ill treatment.She rebels them bravely.Second,when she studies at Lowood,her rebellious spirit is exposed furtherly.Her view doest stay in Mrs Reeds,instead turns to the whole society.She makes hypocrisy of so-called charity to be discovered completely.At the same time,she declares her independent,equal rebellious thought to her friend-Helldn who endures oppression willingly.Third,she,as a governess in Thornfield Hall falls in love with Rochester-her master.During this period,her thought grows into maturity.Thought she loves him passionately,she never loses her dignity and independence for him.When she knows his mad wife still lives,she makes up her mind to leave him.For she doesnt want to become his mistress.Fourth,her refusal of St Johns proposal of marriage depicts Janes character.She knows John does not love her at all and his purpose of marriage is only to perform his great task missionary.Jane does want to become a sacrifice.She breaks traditional morality,then she goes back to Rochester.  相似文献   

14.
The context of a word consists of the other words surrounding it and the situation in which it is used.When we come across a new word in our reading,instead of looking it up in a dictionary for its definition,we can guess its meaning from its context.  相似文献   

15.
Introduction Whatisculture?Toputitsimply,culturemeansthe totalwayoflifeofaperson.Thissimpledefinitionimplies thatculturereferstothepattersofcustoms,traditions,socialhabits,values,beliefsandlanguageofasociety.As cultureissoinclusive,itincludesvirtuallyeverythingthat agroupofpeoplethink,say,doandmake.Followingthedefinitionofsociologists,theterm culturereferstothetotalpatternofbeliefs,customs,institutions,objects,andcharacterizesthelifeofhuman community.“Cultureconsistsofallthesharedproductsof …  相似文献   

16.
"Midnight"is a poem written by Archibald·Lampman,a Canadian poet,who loved nature very much,but his poor health prevents him from being very active in the outdoor life.So he is often the quite,thoughtful observer of nature in his poems.This article mainly talks about how to appreciate the poem in the following aspects:word selecting,rhyme,sentence structure and atmosphere.After reading this poem,we cannot get rid of the air of horror and mystery."Midnight" reveals another aspect of the nature:wild,rough and unknown.There is something else in the nature that can awe human beings even though we don't know what it is.  相似文献   

17.
当代中国武术经历了时代的沧桑和变迁,在历经了文化和历史的发展与洗礼之后,依然发展、繁衍至今。在这样一个漫长的过程中,伴随着以社会环境和社会人群价值取向为主的变迁与变化,当代中国武术的发展与当代社会的发展正逐渐的呈现出某些相背离和不和谐的表象。通过研究,我们发觉中国武术中原本一些内在的东西正在不断的被遗忘,正在不断的流逝。本文试从中国武术在当代发展中的问题境域入手,解读中国武术在当今世界和社会中存在的一些问题,希望能够从中找到中国武术发展的"合法性"或"合时性"的内在依据,以挺立中国武术的脊梁。  相似文献   

18.
Chapter Ⅰ Introduction Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.  相似文献   

19.
运用临场观察统计法、访谈法、文献资料法以及归纳法等研究方法,对现阶段国内青少年足球守门员防守技术运用情况进行统计与分析研究.结果表明:判断反应与选位能力不足是青少年守门员防守技术失误的主要原因,预判失误与技术粗糙以及缺乏自信等导致青少年守门员对抗条件下难以有效发挥位置优势,强干扰情况时出击争夺球失误多,重视反应训练和提高接球动作质量要求是提高青少年守门员技术水平的重中之重.  相似文献   

20.
提高体校学生的语素质的主要途径是课堂教学。体校语教师在教学过程中必须根据学生身心特点.设置合理的结构模式,以便顺利实现教学目标。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号