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1.
目的:采用火焰原子吸收光谱测定五倍子中钙、镁、铁、铜、锰、锌6种微量元素的含量。方法:采用硝酸-高氯酸常压250℃条件下消解样品,并进行了方法的准确性和精密度考察。结果:对于所测元素,工作曲线的相关系数r〉0.998 2,回收率96.0%~109.8%,RSD〈4.70%。五倍子中上述6种元素的含量由高到低依次是钙,镁,铁,锌,锰,铜。结论:五倍子中含有较丰富的钙,镁,铁,锌,锰,铜元素。所得数据可为五倍子药物的进一步研究和综合开发利用提供新的科学依据。  相似文献   

2.
了解兰州地区大学生头发中无机盐与微量元素的含量水平。采用原子吸收分光光度法对824大学生头发中的钙、镁、铁、锌、铜、锰等6项元素进行检测与分析。兰州地区大学生头发中6种元素含量均呈偏态分布,钙、镁、铁、锌、铜、锰的含量分别为(1042.69±570.8)、(143.68±72.0)、(119.96±72.8)、(200.72±91.4)、(14.60±11.6)、(18.69±9.9)ug·g-1。其中钙、铁、铜、锰女生高于男生,锌男生高于女生,差异均有异著性(p0.05);与1994年报道相比,锌、铜、锰的含量水平均有明显上升(p0.01),铁的水平有明显下降(p0.01);钙、铁、锌、铜、镁的总体缺乏率分别为13.7%、2.8%、21.1%、10.4%和0.6%,锌缺乏率最高。不同性别间,男生钙和铜的缺乏率均比女生高(p0.01),锌则是女生缺乏率高于男生(p0.01),铁和镁整体缺乏较低,无性别差异,锰无缺乏。兰州地区大学生微量元素营养状况正在改善,但还存在不平衡的问题,建议高校加强营养健康教育,正确引导大学生养成良好的生活行为方式。  相似文献   

3.
应用ICP-AES法同时测定植丰素中的铜、锌、铁、锰、镁含量,结果表明:该方法的回收率为95.9%~107%,相对标准偏差值为0.40%~0.60%,能满足进出口植丰素中的铜、锌、铁、锰、镁含量的测定要求,具有分析速度快、操作简便、检验效率高等优点.  相似文献   

4.
在选用不同消化剂对武功紫红米进行微波消解处理的基础上,利用空气-乙炔火焰原子吸收光谱法测定武功紫红米中铜、锌、镁、锰、铁、钙6种矿物质元素含量。研究结果表明:选择硝酸-过氧化氢(7+3)作为消化剂,能最大程度将武功紫红米消解。6种元素的精密度介于0.003%~0.29%之间,回收率在93.25%~108.35%之间,说明这种方法的精确度和准确度高,可以用于这6种元素的测定。测得该批次的武功紫红米中矿物质元素铜、锌、镁、锰、铁、钙的含量分别为3.17、15.98、1043.56、19.83、10.06、98.30 mg/kg。  相似文献   

5.
刘爱萍 《甘肃科技》2007,23(10):212-213
为探讨卵巢癌患者体内微量元素变化,本文采用原子吸收光谱法测定了25例卵巢癌病人血清中锌、铜、铁、钙、镁、锰、几种元素含量,采用化学法测定硒元素,并与30例正常人为对照。结果表明,卵巢癌患者血清中锌、铁、锰、硒均低于正常人,血清铜与对照组无显著差异,但铜/锌值升高,钙、镁无显著差异。提示:低锌、低锰、低硒与卵巢癌的发生有一定的关系,锌、硒、锰在卵巢癌预防及辅助治疗上均有一定的价值。  相似文献   

6.
本文采用湿法消化试样,火焰原子吸收法测定中药潞党参中铜、铁、锌锰等微量元素,对标准物桃叶测定结果表明方法准确度高,精密度好,适用于中草药中微量元素的测定。  相似文献   

7.
烤烟营养元素分布特征的主组分分析   总被引:3,自引:1,他引:2  
以烤烟为对象,按田间试验和盆栽试验测定其不同生育期叶、茎、根的生育期叶,磷,钾,钙,镁,铁,锰,锌、铜、硼10种元素含量。运用化学计量学中的主组分分析方法,讨论了这些营养元素分布特征,表明,各部位有特征元素,硫,磷,钾,钙,镁等中常量元素,在烟叶中有较高的浓度分布,而烤烟中的铁,锰,锌,铜,硼等微量元素则在根部有较高的浓度分布。提示在进行烤烟矿质的植株诊断时要十分注意不同部位的差异,也说明了可将化  相似文献   

8.
用等离子体发射光谱测试吉林大学120名男、女学生发样中锰、锌、铜、铁、钙元素的质量比,并将所得数据用SPSS10.0进行非参数检验.结果表明:男女生发样中锌、铜质量比在正常值范围内,铁的质量比偏高;男女生发样中锰的质量比和男生发样中钙的质量比均低于参考值;男女生发样中的铜、锌和钙的质量比及大一女生和大二女生发样中锰和铜的质量比存在统计学上的显著性差异.  相似文献   

9.
用火焰原子吸收分光光度法测定了山茱萸中的铁、铜、镁、锌、锰、铬、铅、镉八种微量元素的含量.结果表明镁含量很高,铁、铜、铬、锌、锰含量较高,铅含量很低,不合镉.  相似文献   

10.
铅测定方法是基于使铅生成硫酸铅沉淀,与锌、铜、铁、锰等元素分离、而后将硫酸铅转化为醋酸铅,在 pH 5.5—6的溶液中,以二甲酚橙作指示剂,以 EDTA 标准溶液滴定铅。锌的测定法基于硝酸、氯酸钾溶矿测定铅后的分离液中测定锌。以氢氧化铵、溴水等沉淀铁、锰、铝分离除去干扰,在 pH5—6的条件下,以 EDTA 滴定锌。其反应式:H_2Y~(-2)+Zn~(+2)→ZnY~(-2)+2H~+ 铜、镉干扰滴定以碘化钾、硫代硫酸钠消除。铝、钡、铁等部分残余干扰元素,分别以氟化铵、酒石酸消除。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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