原子吸收光谱法测定葛花微量元素的含量

葛花具有多种保健和医疗功效,为了解其花部的人体必需微量元素含量,研究采用HCl和HN03混合液消解样品,用原子吸收光谱法对其花中的Fe,Cu,Zn,Mn四种元素进行了分析测定.方法的加标回收率为97.57%～100.27%,RSD值小于1.34%,具有良好的准确度和精密度,完全可以满足葛花样品中人体必需微量金属元素的测定要求.测定结果表明:葛花中Fe,Cu,Zn,Mn含量分别为237.62μg·g-1,14.13 μg·g-1,28.17μg·g-,1,16.12μg·g-1,四种元素含量由高到低的顺序是Fe＞Zn＞Mn＞Cu.证明葛花中Fe,Cu,Zn,Mn含量丰富.研究为进一步科学合理地利用葛花提供了依据.     

不同产地白花蛇舌草元素含量测定分析

为了比较不同产地的白花蛇舌草的差异,测定了6个不同产地的白花蛇舌草中主要元素的含量。实验采用电热套改进装置消解,原子吸收火焰法进行测定,并分析比较元素含量与其药理作用的关系。结果测得白花蛇舌草中Ca,Mn,Fe,Cu,Zn,Mg等元素含量较高,其中Mn的最低含量达224.7μg/g,云南产地白花蛇舌草Mn含量达到1 362.6μg/g,R2=0.991 3~0.998 4,回收率90%~108%。元素分析结果表明:白花蛇舌草中6种元素含量较高,是其具有很好的清热解毒作用和很强的癌抑制作用的依据。     

湿法消解-火焰原子吸收光谱法测定两种茶叶中锌、铁、铜、锰的含量

本实验采用湿法消解处理样品、火焰原子吸收光谱法测定样品溶液中的四种微量元素.结果:北川绿茶中Zn、Fe、Cu、Mn的含量分别为10.60μg/g、66.55μg/g、8.80μg/g、145.8μg/g,北川茉莉花茶中Zn、Fe、Cu、Mn的含量分别为11.40μg/g、64.35μg/g、9.20μg/g、149.2μg/g.两种茶叶的相对标准偏差(RSD)均小于1.0%,线性范围在0.00²0.00μg·m L-1,平均回收率在95.5%20.00μg·m L-1,平均回收率在95.5%¹01.0%.该方法简单、快速、准确性高用于两种茶中四种微量元素的测定,结果令人满意.     

火焰原子吸收光谱法测定肾豆中四种微量元素的含量

用火焰原子吸收光谱法测定了肾豆中铁、铜、锌、锰等四种微量元素的含量.本试验方法的相对标准偏差在0.72%~2.51%之间,加标回收率在96.0%~100.5%之间.结果表明,肾豆中铁元素、铜元素、锌元素、锰元素含量分别是65.5μg·g-1,11.0μg·g-1,29.2μg·g-1,11.8μg·g-1,说明肾豆中含有人体必须的铁、铜、锌、锰等微量元素.本试验方法简便、经济、准确、可靠.     

AAS法测定亳白芍水提液中微量元素的含量

目的:探讨AAS法测定亳白芍水提液中Fe、Mn、Zn元素含量的可行性及准确性.方法:采用索氏提取法处理样品,用火焰原子吸收光谱法测定亳白芍水提液中Fe、Mn、Zn元素的含量.结果:亳白芍水提液中含有Fe、Mn、Zn等微量元素,线性范围(μg·mL-1):Fe 1.000～9.000,Zn 0.500～4.000,Mn 0.400～4.000;平均回收率:Fe 101.4%,Zn 101.4%,Mn 107.5%;相对标准偏差(RSD):Fe 4.31%,Zn 5.22%,Mn 2.79%.结论:亳白芍中含有丰富的对人体有益的微量元素.该测定方法简便,精密度及重复性均较好.     

原子吸收法测定当归补血汤等方剂中常见微量元素

为了研究经典方剂中微量元素含量与疗效之间的关系,用原子吸收光谱法对当归补血汤、归脾汤、六味地黄汤3个方剂中的Cu、Zn、Fe、Mn、Co等5种微量元素进行了测定.结果表明:当归补血汤中的Zn、Fe、Mn含量分别为36.75μg/g、500.25μg/g和28.31μg/g,均远高于其他两种方剂.从微量元素的角度来看,当归补血汤的补血效果应该更好.     

FAAS法测定山丹黄参中金属元素Ca、Mg、Fe、Cu、Zn、Pb的含量

目的:测定山丹黄参中金属元素Mg、Ca、Fe、Cu、Zn、Pb的含量.方法:采用浓硝酸—高氯酸(V∶V=4∶1)常压微沸条件下消解黄参样品,应用火焰原子吸收法(FAAS)测定黄参中的金属元素Mg、Ca、Fe、Cu、Zn、Pb的含量,研究了测定不同元素的仪器最佳工作条件,并作了测定方法的准确性和精密度考察.结果:山丹黄参中Mg、Ca、Fe、Cu、Zn、Pb的含量分别为1932.8、3272.1、687.6、7.3、17.1μg.g-1,Pb未检出.方法的加标回收率为97.50%～102.16%,相对标准偏差(n=9)为0.21%～1.46%.结论:测定方法简单易行,方便快捷,结果可靠.     

原子吸收光谱法测定几种蕨类中矿质元素含量

采用原子吸收光谱法测定了凤尾草、贯众、海金沙、蜈蚣草中Ca、Mg、Cu、Zn、Mn、Fe、Pb、Cd等8种元素的含量.结果表明.几种蕨类药材中矿物质元素Ca、Mg、Cu、Fe、Zn、Mn含量丰富,Cu含量小于9.89μg/g,Pb、Cd含量低,均符合《中国药典》2005年版重金属及有害元素限量要求,矿物质元素含量与生长环境及药材对元素的富集作用存在一定关系,部分元素含量与药材种类及区域不同具有显著性差异.测定结果相对偏差小于4.3%,工作曲线回归方程的相关系数在0.9984~1.000之间,加标回收率为92.5%~105.3%.     

三种长白山野生食用菌多糖和微量元素含量测定

目的测定三种长白山野生食用菌—牛肝菌、密环菌、香菇的中多糖和微量元素的含量.方法采用水提醇沉法提取多糖,苯酚—硫酸法测定多糖含量,火焰原子吸收光谱法测定Ca、Fe、Zn、Mg四种微量元素的含量.结果牛肝菌、密环菌、香菇中多糖含量依次为7.67%、14.45%6、.92%.微量元素含量依次为（μg.g-1）：Fe：910.97,69.4,473.0,Ca：176.1,68.8,141.7;Mg：34.3,25.33,0.1;Zn：128.7,83.91,24.9.结论三种长白山野生食用菌均含有丰富的多糖和微量元素,其中密环菌多糖含量最高,牛肚菌微量元素含量最高.     

大别山葛根微量矿质元素测定及对比分析

为客观了解大别山区葛根微量矿质元素含量,运用国标检测方法,对大别山腹地自然野生葛根和人工种植葛根Fe、Zn、Cu、I、Mn、Se元素含量进行测定,其结果为:人工种植组平均含量分别为58.76μg/g,11.36μg/g,4.85μg/g,3.13μg/g,7.66 1μg/g,1.21μg/g;自然野生组平均含量分别为257.33μg/g,91.58μg/g,6.29μg/g,3.83μg/g,9.23μg/g,1.23μg/g。说明:在葛根Fe、Zn微量矿质元素利用开发方面,自然野生组葛具有优越性,而其他矿质元素差异不明显。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.