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悬浮液进样火焰原子吸收光谱法测定百合中的锌和锰 总被引：1，自引：0，他引：1
将处理后的百合研磨成粒度小于0.1 mm的粉状物,加入稳定剂琼脂制成悬浮液,用LaCl3消除相关化学干扰,采用标准加入法在同一试液中利用空气—乙炔火焰原子吸收光谱法测定锌和锰元素含量.结果表明,兰州百合中Zn和Mn的含量分别是162.02μg.g-1、4.95μg.g-1,且Zn和Mn的加标回收率分别为99.35%~112.60%、92.00%~101.50%.以传统湿法的测定结果为参考对测定值进行t检验,发现两者无显著性差异,说明悬浮液进样法的测定结果准确可靠. 相似文献
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用湿法消化法处理样品,建立湿法消化法-火焰原子吸收光谱法快速测定蝉蜕中钙、铁、锌、锰、铜、镉6种微量元素的分析方法。实验结果表明,在待测液中加入适量盐酸可提高被测元素的吸光度。详细研究了HClO4和HNO3的两种不同体积比对测定结果的影响,前者回收率为96．2％-123．4％,后者回收率为97．3％-108．1％。相对标准偏差小于1．4％,标准偏差小于2．6％。 相似文献
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铝锰合金样品用过氧化钠熔融,使样品完全分解后,加乙醇煮沸使高价锰还原,消除高价锰的干扰,再利用铝是两性元素的特性,使铁、锰、钛生成碱性氧化物沉淀,过滤与铝分离。然后采用EDTA容量法可测得铝锰合金中铝量。该方法一次分离,简便、快速、准确,可适用于测定铝锰合金中10%~50%的铝量。其相对标准偏差(RSD,n=5)小于0.5%,加标回收率98.5%~101%。 相似文献
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介绍了一种悬浮液进样火焰原子吸收光谱法（FAAS）测定怀地黄中铜的方法。以琼脂为悬浮剂将粉碎、过筛的怀地黄样品均匀、稳定地悬浮于琼脂溶胶中,直接喷入空气-乙炔火焰中,采用标准加入法测定,省去了以往繁琐的样品化学前处理过程,解决了因操作环节多,被测元素丢失或污染所引起的分析误差。用该法测定怀地黄样品,并与湿法消化法对照,获得满意结果。该方法简便、快速,准确,可以代替湿法消化法。 相似文献
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本文应用二甲酚橙分光光度法测定植株中钙、镁.样品首先采用H_2SO_4-H_2O_2-HCLO_4法进行快速消化,二甲酚橙在PHl0.8NH_4OH-NH_4CL缓冲液中与钙、镁配合,用EGTA.8羟基喹啉、硫代乙醇酸、三乙醇胺等掩蔽剂,详细研究了在各种实验条件下对钙、镁测定的影响与干扰.最终在自动分析中使用二甲酚橙分光光度法测定植株中的钙、镁、磷、钾. 相似文献
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用蒸馏水将烘干、研碎后的铁观音茶叶样品制成均匀悬浊液,用SrCl2来消除相关干扰,然后直接进样,通过火焰原子吸收法测定锰的含量.优化条件下,悬浊液进样-火焰原子吸收法在实验范围内,线性关系良好,方法的检出限为0.079 mg/L,加标回收率为95.8%~99.8%,相对标准偏差为1.7%.该法简便、快速、准确,用于实际样品测定结果满意. 相似文献
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王晓艳 《河北能源职业技术学院学报》2009,9(3):65-67
将非完全消化法应用于火焰原子吸收光谱法,成功地测定了人造奶油中的微量镍。在低温下用高氯酸：硝酸（1：3,v／v）混合酸消解样品,再用20％的OP乳化剂溶液溶解消解过程中产生的油脂,配制成均匀、淡黄色、稳定的样品溶液。以空白溶液为参比,用工作曲线法测定,建立了测定人造奶油中镍的快速火焰原子吸收光谱法,该方法简便、快速、准确,加标回收率为94．15％～108％。 相似文献
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鸡蛋壳中钙镁含量的测定 总被引：1，自引：0，他引：1
分别采用干式灰化法、湿式消化法、直接酸溶法处理蛋壳,并对上述三种方法进行了比较,从中选择出适合实验教学的简便方法为直接酸溶法。采用EDTA络合滴定法测定鸡蛋壳样品中的钙、镁含量分别约为38．77％．0．49％。 相似文献
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石墨炉原子吸收法测定自来水中的有害元素铅 总被引：1，自引：0，他引：1
采用石墨炉原子吸收光谱法,水样处理后加入基体改进剂,测定水中有害元素痕量铅.实验优化了石墨炉原子吸收光谱法的测定条件.重点讨论了铅的灰化温度、原子化温度以及基体改进剂的选用对铅测定结果的影响,结果表明,以磷酸二氢盐、钯盐为基体改进剂可提高灰化温度,消除样品中的钙、镁、钠等复杂基体的干扰,相对标准偏差为2.23%,回收率为94.0%-102.0%,具有良好的精密度和回收率.方法简便快速、结果准确. 相似文献
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《海外英语》2007,(5):10-11
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? 相似文献
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邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
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《海外英语》2007,(4):36
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. 相似文献
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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. 相似文献
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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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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. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献