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1.
8-羟基喹啉萃取双波长分光光度法测定铬铁矿中铝、铁已有报导。由于8-羟基喹啉与铝形成不溶性的络合物,故不能在水相中直接显色测定。Katsumi Goto等介绍应用铁试剂(7-碘-8-羟基喹啉-5-磺酸,即Ferron)可省略萃取步骤。徐辉远也阐述由于磺酸基的存在,增大了络合物的溶解度,但所形成络合物的络合比及稳定性受到溶液酸度及其它  相似文献   

2.
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   

3.
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   

4.
一阶导数吸光光度法同时测定纯硅中铁和铝的研究   总被引:4,自引:0,他引:4  
提出了用一阶导数光光度法同时测定铁和铝的方法,在pH6.5乙二胺缓冲溶液中,乳化剂OP存在下,Fe^3+Al^3+与络天青S形成Fe^3+,Al^3+-CAS-OP三元络合物,络合物一阶导数光谱等吸收点分别在606.2,638.0nm记录混合体系在两波长处一阶导数数值可以分别测定铝,铁含量,互不影响,铁,铝含量分别在1.0~16μg/25ml,0.3~10μg/25ml范围内呈良好线性,用于测定纯  相似文献   

5.
在溴化十六烷基吡啶(CPB)存在下,用分光光度法研究了茜素黄GG与铁(Ⅲ)的显色反应性能.在pH 8.0~10.0范围内,茜素黄GG与铁(Ⅲ)形成3:1的红色络合物.该络合物的最大吸收波长在470 nm处.铁的质量浓度在1.0 mg·L-1以内服从比耳定律,表观摩尔吸光率为5.281×104L·mol-1·cm-1.所拟方法用于纯铝及铝合金样品中微量铁的测定,测定值与已知值相符,测定值的相对标准偏差(n=8)均小于3%.  相似文献   

6.
在邻二氮菲(Phen)、铬天青S(CAS)和十四烷基二甲基苄基氯化铵(TDMBA)的共同存在下,于pH 5~6的酸性介质中,铁、铝分别生成Fe-Phen和Al-CAS-TDMBA络合物,用同一份试液,在波长510 nm测定铁,在625 nm测定铝,两种络合物互不干扰。用该法可同时测定硅石中的铁和铝。  相似文献   

7.
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   

8.
设计合成了双8-羟基喹啉端的开链冠醚QP3Q,研究了金属离子铝或锌与其形成络合物的组成和发光性质,并测定了络合物的激发态寿命.这些络合物在溶液中有较高的荧光量子产率,所得到的络合物固体具有较强的蓝光发光性能.结果表明,有可能通过QP3Q与不同离子形成的络合物得到不同发光波长的发光材料.  相似文献   

9.
8-羟基喹哪啶固相萃取光度法测定水样中的铁   总被引:4,自引:0,他引:4  
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,在十六烷基三甲基溴化铵(CTMAB)存在下,8-羟基喹哪啶与铁反应生成3:1稳定的蓝紫色络合物,该络合物可被Waters Sep-Park-C18固相萃取小柱萃取,用乙醇洗脱后用光度法测定,络合物λmax=600nm。在此波长下其它金属离子的络合物无光吸收,对铁选择性很好,铁含量在0-5mg/L内符合比尔定律,方法用于水样中痕量铁的测定,结果令人满意。  相似文献   

10.
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   

11.
Hydrotalcite-like compounds (HTlc) are composed of trivalent and divalent metal ions, the general formula 1 is: [M2+1-xM3+x(OH)2]x+An-x/n·mH2O M3+ is trivalent metal ions, M2+is divalent metal ions, A is negative ions whose valence is n, and m is the amount of water in the crystal, and x is the molar ratio of trivalent metal ions to all metal ions. A lot of studies have been done on the synthesis and property of HTlc, which is made up of two kinds of the metal ions. It has been found …  相似文献   

12.
IntroductionLayered double hydroxides( LDHs) with hy-drotalcite ( HT ) - type structure are composed oftrivalent and divalent metal ions and have the gen-eral formula[1] ,[M2 + 1-x M3 + x ( OH) 2 ]x+ An-x/ n· m H2 O,where M3 + is a trivalentmental ion,such as Al3 + ,Fe3 + ,La3 + ,Ni3 + ,Mn3 + etc.,M2 + is a divalentmetal ion,such as Mg2 + ,Zn2 + ,Ca2 + ,Cu2 + ,Co2 +etc.,An-is a charge compensating anion,such asOH-,Cl-,NO-3 ,CO2 -3 etc.,m is the number ofthe moles of co- intercalat…  相似文献   

13.
A spectrophotometric method for simultaneous determination of Al(III) and Fe(III) using the chelator Desferal® (desferrioxamine B) was developed. Partial least squares (PLS) regression was performed to resolve the overlapped signals obtained from Al(III) and Fe(III) complexes. The parameters controlling behavior of the system were investigated and optimum conditions were selected. PLS was the choice for the analysis of binary mixtures of Fe(III) and Al(III) over the range of 0.1 to 0.8 mg L?1 by using the data of first derivative spectra. Absorbance data were taken between 200 and 600 nm. The calculated sensitivity values for the multivariate method were 4.88 and 5.64 for Al(III) and Fe(III), respectively. Multivariate detection limits were 0.075 and 0.064 mg L?1 for Al(III) and Fe(III), respectively. The method was applied to real post-hemodialysis samples, and sample digestion by UV irradiation was discussed.  相似文献   

14.
采用分子动力学(MD)方法模拟了不同半径大小的纳米Al2O3颗粒夹杂在三个温度下(1750、1730和1710K)对纯Fe液的诱导凝固过程,并分析了作为诱导核心的纳米Al2O3颗粒的结构演变及其对Fe原子体系的凝固过程的影响.发现在诱导过程中,纳米Al2O3颗粒的内部保持较好的晶型结构,仅表面原子有结构变形;诱导凝固的Fe原子主要为面心立方(fcc)和密排六方(hcp)原子;纳米Al2O3颗粒的尺寸越大,发生诱导凝固的温度越高;诱导凝固得到的Fe晶体的晶格取向受纳米Al2O3颗粒在Fe液中的漂移程度影响.  相似文献   

15.
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   

16.
用溶胶—凝胶法合成了非晶态Fe0.5Al0.5PO4。用XRD和TPR表征了其结构和晶格氧的活性;用IR和TPD表征了CH4在其表面上的吸附行为;用LSSR方法考察了CH4直接氧化合成CH3OH的反应规律。结果表明,Fe0.5Al0.5PO4具有非晶态的结构,FePO4和AlPO4的微区被均匀地相互隔离,导致固体本身不具有长程有序性。非晶态的Fe0.5Al0.5PO4与晶态的Fe0.5Al0.5PO4相比,其晶格氧的活性大且活性氧的含量高。CH4以分子态吸附于固体表面P=O键上,非晶态Fe0.5Al0.5PO4表面上CH4的吸附强度和吸附量都较晶态Fe0.5Al0.5PO4上大。用1073 cm-1的激光激发固体表面P=O键,在100℃以上CH4的直接氧化反应顺利进行,CH3OH保持高选择性。在相同的反应条件下,非晶态Fe0.5Al0.5PO4能更有效地促进反应的进行,表明在激发相同表面化学键的情况下,固体表面材料的其它性质如粒度、比表面积和晶格氧的活性对反应也有一定程度的影响。  相似文献   

17.
采用过氧化钠和氢氧化钠高温熔融铬矿石样品,以盐酸溶解熔块,合并溶液后用电感耦合等离子体原子发射光谱法测定样品中硅、铝、镁和铁的含量。选择212.412,308.215,285.213,238.204 nm分别作为硅、铝、镁、铁的分析谱线。用铬矿石标准样品配制标准溶液,对标准溶液的贮存方法进行了研究,对影响标准曲线稳定性的因素进行了讨论。SiO2、Fe2O3、Al2O3和MgO的线性范围依次为0.61%~14.64%,13.62%~27.74%,9.29%~15.17%和9.87%~21.49%。采用该法对铬矿石样品进行30d的连续测定,SiO2、Fe2O3、Al2O3和MgO测定值的相对标准偏差分别在0.51%~1.3%,0.45%~2.0%,0.50%~2.5%和1.4%~2.3%之间。  相似文献   

18.
A new, simple, sensitive and selective method for the simultaneous determination of trace iron and aluminum by catalytic spectrophotometry was presented, based on the catalytic effects of iron and aluminum on the discoloring reaction of xylene cyanol FF proceeded by hydrogen peroxide and potassium periodate in weak nitric acid medium. No catalytic effect was obtained in the presence of hydrogen peroxide or potassium periodate only. With the conditional rate constants determined in reaction systems catalyzed by Al or Fe only, the concentrations of Fe and Al in the samples can be calculated. The method was applied to the simultaneous determination of trace Fe and Al in tap water, lake water, river water and tea leaves without separation and preconcentration.  相似文献   

19.
Insufficient understanding of the interactions of reactive phases (e.g., Fe and Al oxides) with minerals, other reactive phases and sorbing species has made predicting and modeling metal sorption on natural sediment surfaces difficult. This work develops a method to create mixed Fe/Al planar oxide surfaces by coating well-characterized planar gamma-Al2O3 with ferric iron. The objective is to closely control the Fe/Al ratio as well as the distribution of Fe on the planar surface. Effects of starting Fe(III) concentration, reaction time and number of coating sequences were examined using XPS and ToF-SIMS. No observable trend was seen in Fe/Al ratios by varying the starting Fe(III) concentration or reaction time. For both 4- and 14-day reactions, lower concentrations of Fe(III) produced oxide phases with a homogeneous distribution of Fe at the surface as detected by ToF-SIMS. ToF-SIMS Fe elemental maps of the oxide phases resulting from the highest Fe(III) concentration showed areas of localized Fe deposition. A sequential coating procedure allowed for a closer control of the concentration and spatial distribution of Fe(III) in the resulting oxide phase. This work provides methodology that can be used to create Fe/Al oxide phases whose Fe/Al content can be controlled for use in subsequent sorption studies to better understand the effects of mixed phase oxides on metal ion uptake.  相似文献   

20.
采用碱熔法,以移液枪分取试样,用电感耦合等离子体原子发射光谱法同时分析石灰石中铁、铝、钙、镁、硅5种化学成分。在分析过程中对氩气加湿,避免盐析效应的影响,铁、铝、钙、镁、硅的分析谱线分别为259.940,396.152,315.887,279.553,251.611 nm。5种成分在各自的线性范围内均具有良好的线性,线性相关系数在0.990 74~0.999 99之间,方法检出限为0.000 6%~0.005 1%,回收率为95.6%~105.4%,测定结果的相对标准偏差小于1%(n=6)。该方法检出限低、重现性好,适合于石灰石样品中铁、铝、钙、镁、硅的快速检测。  相似文献   

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