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1.
流动注射—双显色剂双波长分光光度法同时测定铝与铁   总被引:1,自引:0,他引:1  
本文将流动注射与双波长双光束分光光度计联用,选择铬天菁S和亚硝基R盐双显色剂使AI(Ⅲ)和Fe(Ⅱ)同时显色。建立了同时测定铝、铁的流动注射-双波长等吸收法。方法用于岩矿样品中铝、铁的测定,结果满意。  相似文献   

2.
双波长分光光度法同时测定灌木饲料中的铁和铝   总被引:4,自引:0,他引:4  
利用铁、铝与邻苯二酚紫(PCV)形成的络合物的最大吸收波长相差30nm的光谱性质,建立了同时测定铁和铝的双波长分光光度法,并对络合物的形成条件及相互干扰情况进行研究,方法用于灌木饲料样品中铁和铝测定。  相似文献   

3.
双显色剂双波长系数补偿法同时测定铝和铁的研究   总被引:4,自引:0,他引:4  
本文提出了一种双显色双波长系数补偿法测定食品中微量铝、铁的新方法,在pH=6.2缓冲液中,以络天青S为显色剂选择622/506nm波长对测定铝,以5-Br-PADAP为显色剂选择560/660nm波长对测定铁,不经分离可直接测定样品中的铝、铁,铝量在0.2~5.0μg/25ml、铁量在1.0~15.0μg/25ml符合朗伯比耳定律。本法应用于食品中铝、铁测定,得到较满意结果。  相似文献   

4.
研究了新显色剂二甲氧基羟基苯基荧光酮(DMH-PF)双波长分光光度同时测定铝和铁的新方法。在氨性介质中,氟化钠及Triton X-100 存在下,铝、铁与试剂分别形成红色和紫色配合物,最大吸收波长分别为547 nm 和578 nm 。选定铝的测定波长对为547~615.5 nm ,铁的测定波长为610 nm ,表观摩尔吸收系数ε547Al = 1.67×105 L·m ol- 1 ·cm - 1,ε610Fe = 8.30×104 L·m ol- 1·cm - 1,0~3 μg Al3+ /25m L和0~6 μg Fe3+ /25m L范围内符合比耳定律。应用于工业硅中铝和铁的同时测定,获得满意结果。  相似文献   

5.
流动注射标准加入双波长光度法同时测定铁和铝   总被引:5,自引:1,他引:5  
研究了用流动注射分析(FIA)进行双波长标准加入法同时测定铁和铝的新方法.方法基于在溴化十六烷基三甲胺存在下,络天青S与铁和铝在同一酸度(pH 6.75)均有灵敏的显色反应,但两配合物的吸收光谱互相重叠.在优化的试验条件下,铁和铝检出限分别为0.001和0.002μg·ml~(-1),铁浓度在0~1.2μg·ml~(-1)、铝浓度在0~0.8μg·ml~(-1)时服从比耳定律,测样频率为60样·h~(-1),所拟方法用于实际样品分析,结果良好.  相似文献   

6.
以铁(或铝)-铬天青S-十二烷基二聚氧乙烯基氨基甲酸多元络合物体系的双波长分光光度法,可不经分离,同时测定铁和铝。定铝的波长对是610.0-639.5nm;定铁的波长对是630.0—579.5nm。应用该法测定了硅石、硅砖、纯硅及白云石中的铁铝含量,并以加入法检验回收,结果较满意。  相似文献   

7.
研究了Al(Fe)-CAS、Al(Fe)-CAB在不同增溶体系中的双波长光度行为,提出了双波长等吸收法中“非零等吸收点”的可用性,并在铝铁同时测定中得到验证。  相似文献   

8.
提高灵敏度与改善选择性一直是光度分析研究的重要课题,为此近年来提出了许多方法,但部分改善选择性的方法如双波长[1]及三波长法等往往导致灵敏度下降。标准加入双波长光度法[2]是基于等吸收双波长法原理及标准加入法的特点而设计的,该法可消除干扰、改善选择性且不致降低灵敏度。本文在弱酸性介质中,以络天青S(CAS)为显色剂,采用标准加入双波长光度法,建立了同时测定微量铝、铁的方法。本法Al(Ⅲ)的测定范围0.01~0.35mg·L-1,Fe(Ⅲ)的测定范围0.05~0.40mg·L-1,用于二元混合物中铝、铁的同时测定,结果的准确度和精密度均较高。1…  相似文献   

9.
流动注射停流—分光光度法同时测定痕量铝和铁   总被引:9,自引:0,他引:9  
在弱酸性溶液中,基于铝、铁与铬天青S、溴化十六烷基吡啶形成蓝色三元络合物,采用两次标准加入法,建立了流动注射停流技术同时测定铝、铁的新方法。测定频率90次/h。铝、铁的线性范围分别为0-0.4mg/L,和0-0.8mg/L。应用于水及食品中痕量铝、铁的测定,结果满意。  相似文献   

10.
本文以络菁R(ECR)为显色剂,在六次甲基四胺缓冲体系中,用双波长分光光度法,在751型分光光度计上,顺利地进行了铝铁的同时测定。对混合试样及实物分析表明,操作简便,选择性好。由于将双波长的优越性扩展到通用分光光度计上进行,因此便于普及推广。  相似文献   

11.
多环芳二酐型聚酯亚胺膜的透气性能李悦生,丁孟贤,徐纪平(浙江大学高分子科学与工程研究所,杭州,310027)(中国科学院长春应用化学研究所)关键词聚醚酰亚胺,聚酯酰亚胺,膜,透气性通常的聚酰亚胺加工性能较差,在芳环二酐的苯环间引入醚键等柔性基团后,其...  相似文献   

12.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

13.
微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述,包括:微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。  相似文献   

14.
15.
Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.  相似文献   

16.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB5型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。  相似文献   

17.
In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.  相似文献   

18.
钒与糖代谢及糖尿病   总被引:1,自引:0,他引:1  
微量元素钒作为生物体内必需元素,经证实有很重要的生理学功能,与机体糖代谢有十分密切的关系,且能降低糖尿病动物模型的高血糖,极有可能被开发为治疗糖尿病的药物。  相似文献   

19.
Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.  相似文献   

20.
The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R2UPh type and -thioureas of the R2TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.  相似文献   

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