多波长线性回归法校正火焰原子吸收光谱干扰

用多波长线性回归法校正了火焰原子吸收分析中Ｇａ４０３．２９８ｎｍ对Ｍｎ４０３．３０７ｎｍ的吸收线重叠干扰，对合成样中Ｍｎ和Ｇａ含量的测定，结果令人满意。     

火焰原子吸收光测定合成羰基镍残渣中高含量的铜钴镍铁

本文研究了用火焰原子吸收光谱法测定合成羰基镍残渣中高含量Ｃｕ，Ｃｏ，Ｎｉ，Ｆｅ，系统地试验了测定条件和Ｈ２ＳＯ４浓度，Ｓｉ含量对测定的影响，以及Ｃｕ，Ｃｏ，Ｎｉ，Ｆｅ之间相互干扰情况，研究了合适的溶样方法，选择理想了的分析谱线等，有效地消除了共存元素的干扰，实现了在同一溶液中测定合成羰基镍残渣中的高含量多元素，方法简便，快速，准确。     

亚硝基红盐吸光光度法同时测定铜铁钴

研究在ＰＨ５时，以亚硝酸红盐为显色剂在同一份溶液中分别测定铜、铁、钴，７２０ｎｍ测定铁时钴不干扰，铜干扰用Ｋ系数校正，Ｆｅ－ＮＲＳ络合物在４７０－５６０ｎｍ无吸收，钴、铜测定波长选在５５０、４９０ｎｍ，用Ｋ系数相互校正干扰，方法简便快速，相对标准偏差≤６％，     

火焰原子吸收法测定合成羰基镍残渣中高含量的铜钴镍铁

本文研究了用火焰原子吸收光谱法测定合成碳基镍残渣中高含量Ｃｕ、Ｃｏ、Ｎｉ、Ｆｅ，系统地试验了测定条件和Ｈ＿２ＳＯ＿４浓度、Ｓｉ含量对测定的影响，以及Ｃｕ、Ｃｏ、Ｎｉ、Ｆｅ之间的相互干扰情况，研究了合适的溶样方法，选择理想了的分析谱线等，有效地消除了共存元素的干扰，实现了在同一溶液中测定合成基镍残渣中的高含量多元素，方法简便，快速，准确。     

LaNi5和CeNi5标准生成自由能的研究

用０．９５Ｌａｆ３．０．０５ＣａＦ２多晶固体电解质组成原电池测定了ＬａＮｉ５和ＣｅＮｉ５标准生成自由能与温度的关系，电池形式如下：Ｍｏ｜Ｌａ，Ｌａｆ３｜０．９５ＬａＦ３．０．０５ＣａＦ２｜ＬａＮｉ５，Ｎｉ，ＬａＦ３｜Ｍｏ（９０３～１１７３Ｋ）；ＭＯ｜Ｌａ｜０．９５ＬａＦ３．０．０５ＣａＦ２｜ＬａＮｉ５，Ｎｉ｜Ｍｏ（９０３～１１７３Ｋ）；Ｍｏ｜Ｃｅ，ＣｅＦ３｜０．９５ＬａＦ３．０．０５ＣａＦ２｜Ｃｅ     

火焰原子吸收法连续测定肥料中多元素

应用火焰原子吸收法连续测定肥料中Ｃｕ、Ｚｎ、Ｆｅ、Ｍｎ、Ｃａ、Ｍｇ，并对测定条件、干扰因素进行了综合考察。方法简便、快速、适用于多元素复合肥料生产控制分析和样品系统分析。     

原子吸收法直接测定食用L-赖氨酸盐酸盐中的锌和铁

1 引 言作为食品营养强化剂，Ｌ－赖氨酸盐酸盐越来越受到人们的青睐。据报道，目前在国际上氨基酸工业中，除谷氨酸外，生产最多的是Ｌ－赖氨酸。产品的质量与人体健康密切相关，Ｚｎ和Ｆｅ的含量是Ｌ－赖氨酸产品质量的重要指标，我们选择石墨炉－原子吸收法对这两种元素进行了测定。样品的预处理，诸如湿法消解、干法灰化、萃取等，易引起待测成分的逸失或干扰测定结果，使操作繁琐，分析时间延长。本实验将样品用稀酸溶解，直接注入石墨炉进行Ｚｎ和Ｆｅ的测定。操作简便、快速，缩短了分析周期。2 实验部分2．且 仪骼与试剂 仪器：ＡＡ…     

停留—催化反应速差动力学法同时测定Fe,Mo

根据Ｆｅ（Ⅲ）、Ｍｏ（Ⅵ）对Ｈ２Ｏ２氧化邻氨基酚的催化反应速率不同，结合流动注射停留技术，建立了同时测定Ｆｅ（Ⅲ）、Ｍｏ（Ⅵ）的速差动力学分光光度法．测定铁和钼的线性范围分别为０．１～２．５μｇ／ｍＬ和０．５～１５μｇ／ｍＬ．除Ｗ（Ⅵ）的允许量较小外，其它离子不干扰测定．用本法测定了合成样液中铁和钼含量，结果满意．     

环状配合物Me_2Si［η~5－C_5H_4Fe（CO）_2］_2SnR_2的合

通过ＳｎＣｌ_２对化合物Ｍｅ_２Ｓｉ［η~５－Ｃ_５Ｈ_４Ｆｅ（ＣＯ）］_２（μ－ＣＯ）_２（Ⅰ）中Ｆｅ－Ｆｅ键的插入反应以及Ⅰ被Ｎａ－Ｈｇ齐还原所生成的相应双铁负离子｛Ｍｅ_２Ｓｉ［η~５－Ｃ_５Ｈ_４Ｆｅ（ＣＯ）_２］_２｝~（２－）与ＳｎＲ_２Ｃｌ_２（Ｒ＝Ｍｅ，Ｐｈ）的亲核反应，合成了环状化合物Ｍｅ_２Ｓｉ［η~５－Ｃ_５Ｈ_４Ｆｅ（ＣＯ）_２］_２ＳｎＲ_２［Ｒ＝Ｃｌ（１），Ｍｅ（２），Ｐｈ（３）］。以元素分析、ＩＲ和~１ＨＮＭＲ谱表征了它们的结构，并用Ｘ射线衍射测定了配合物３的晶体结构。３为单斜晶系，空间群Ｐ２_１／ｎ，ａ＝１．０３８４（３）ｎｍ，ｂ＝１．６３８４（１）ｎｍ，ｃ＝１．５７６２（５）ｎｍ，β＝９７．９３（２）°，Ｖ＝２．６５６（２）ｎｍ~３，Ｚ＝４，Ｄｘ＝１．７１ｇ／ｍＬ。     

流动注射分析光度法同时测定镍和铁

建立了流动注射（ＦＩＡ）光度法同时测定镍和铁的新方法，以乙酸－乙酸钠缓冲溶液（ＰＨ４．５０）作载液，溴化十六烷基三甲胺作增溶剂，记录５６０ｎｍ处Ｎｉ（Ⅱ）－Ｂｒ－ＰＡＤＡＰ与Ｆｅ（Ⅱ）－Ｂｒ－ＰＡＤＡＰ的峰值吸收之和７４６ｎｍ处Ｆｅ（Ⅱ）－Ｂｒ－ＰＡＤＡＰ的吸不度测定了钠基合金中的镍和铁。两咱离子的定量线性范围分别为０．１０－１．２０ｍｇ／ｌＬ和０．２０－１．６０ｍｇ／Ｌ，检出限为０．０２ｍｇ／Ｌ     

An investigation into the use of platinum ware for silicate analysis

The amount of platinum dissolved from platinum apparatus used for dissolving silicate materials to obtain solutions for analysis has been determined. The study included apparatus made from an alloy containing 95 % platinum and 5 % gold. The affinity of iron and platinum was investigated, together with the problem of removing iron from platinum after the latter has been contaminated during fusions. The behaviour of platinum in a classical scheme for the analysis of silicate materials was investigated and the distribution of the platinum in various precipitates established. Platinum has been found to interfere in commonly used methods for the determination of silica, aluminium, iron, titanium, calcium and magnesium.     

Methyl orange degradation enhanced by hydrogen spillover onto platinum nanocatalyst surface

Following a thermal reduction method, platinum nanoparticles were synthesized and stabilized by polyvinylpyrrolidone. The colloidal platinum nanoparticles were stable for more than 3 months. The micrograph analysis unveiled that the colloidal platinum nanoparticles were well dispersed with an average size of 2.53 nm. The sol–gel‐based inverse micelle strategy was applied to synthesize mesoporous iron oxide material. The colloidal platinum nanoparticles were deposited on mesoporous iron oxide through the capillary inclusion method. The small‐angle X‐ray scattering analysis indicated that the dimension of platinum nanoparticles deposited on mesoporous iron oxide (Pt‐Fe₂O₃) was 2.64 nm. X‐ray photoelectron spectroscopy (XPS) data showed that the binding energy on Pt‐Fe₂O₃ surface decreased owing to mesoporous support–nanoparticle interaction. Both colloidal and deposited platinum nanocatalysts improved the degradation of methyl orange under reduction conditions. The activation energy on the deposited platinum nanocatalyst interface (2.66 kJ mol^?1) was significantly lowered compared with the one on the colloidal platinum nanocatalyst interface (40.63 ± 0.53 kJ mol^?1).     

Voltammetric behavior of the iron(II)-(III) and cerium(III)-(IV) couples in potentiometric titrations at constant current and amperometric titrations with two indicator electrodes

The voltammetric behavior at the rotated platinum electrode of the iron(II)-(lII) and cerium (III)-(IV) couples in sulfuric and hydrochloric acids has been investigated The iron and cerium couples are not reversible at a platinum electrode when current flows in the system, and the current-potential curves deviate considerably from those predicted on the basis of reversibility Titration curves for potentiometric titrations at constant current using one and two indicator electrodes are predicted from the current-potential curves and compared with the experimental curves.The degree of reversibility of the iron couple depends greatly on the pretreatment of the electrode The current-potential curves of the iron couple at a platinum electrode coated with a monomolecular film of platinum oxide approach reversibility while those at a clean electrode are highly irreversible Experimental and calculated titration lines for amperometric titrations using two indicator electrodes are compared, and the effects of medium and applied e.m.f. upon the characteristics of the titration curves are considered.     

Rapid potentiometric determination of the iron oxidation state in silicates

The rapid potentiometric determination of the oxidation state of iron in a wide range of silicates is described. A platinum/platinum—rhodium (20%) bimetallic electrode with a small constant applied current is used for end-point detection. Samples are decomposed in 10–60 min by boiling with hydrofluoric—sulphuric acid in special PTFE decomposition—titration vessels in an atmosphere of nitrogen. Total iron is reduced with mercury-treated zinc or nickel reductors. Sulphides or other constituents do not interfere significantly and the procedures are relatively insensitive to aerial oxidation. The average standard deviation is 0.35% for iron(II) and 0.22% for total iron. The accuracy compares well to the available data for international standard rocks.     

Analysis of platinum for certain elemental imparities by neutron activation

Silver, ruthenium, cobalt, iron, zinc, cadmium and mercury are determined in platinum by neutron-activation analysis. The scheme developed requires the removal of the platinum matrix by reduction and the sequential separation of the elements by ion-exchange chromatography. The method is suitable for the simultaneous determination (at the ppm level) of these elements in milligram quantities of platinum.     

The Direct Electron Transfer of Iron‐containing Metal Organic Frameworks (Mil‐100) and Its Catalysis for the Oxygen Reduction Reaction in Room‐Temperature Alkaline Media on a Glass Carbon Electrode

The most common electrocatalysts for the oxygen reduction reaction (ORR) are platinum‐based ones. This work demonstrates the performance of iron‐containing metal organic frameworks (MOFs) as non‐platinum‐based nano‐electrocatalysts for ORR in an alkaline medium. As a new non‐platinum catalyst to achieve the active sites for the ORR, Mil‐100 (Fe) nanoparticles were used in aqueous KOH by the rotating‐disk electrode method. The main objectives of this study are the investigations on the electron transfer number (n ), Tafel slope, and catalytic performance. The particles size of the obtained powders is in the nanoscale range (approximately 25 nm). The electron transfer number for the ORR on the surface of iron‐containing catalyst is approximately 4, and the Tafel slope of diffusion‐corrected kinetic current density is ~50.7 mV per decade at low overpotential. This work might extend a new non‐precious‐metal catalyst structure for ORR for use in low‐temperature fuel cells.     

Behaviour of ferroin indicator in iron(ii)- dichromate titrations A Critical study

A critical evaluation has been made of the optimum conditions for a successful direct and reverse titration of iron(II) with dichromate, with ferroin as indicator, taking into account the influence of acidity, the catalytic effect of iron(III) and the induction effect of the iron(II)-dichromate reaction on the indicator oxidation reaction. The difference in the behaviour of the indicator in the direct and reverse titrations is believed to be due to the presence of a slow : step in the indicator oxidation mechanism ; this is however surmounted in the reverse titration, making it possible to use the indicator even in a 2N sulphuric add medium for this titration. The higher potentials recorded in the reverse titration are believed to be due to the oxide film on the platinum metal electrode. While iron(III) seems to help lower the kinetic barrier of the slow step sufficiently in the indicator oxidation mechanism, the ferriin-ferroin system seems to help m a similar way toe establishment of a more positive potential of the Ct(VI)/Cr(III) system at the platinum electrode in me direct titration; this value explains the feasibility of the direct visual titration in 2N sulphuric acid, although the colour change at the end-point is slow for other reasons.     

Potentiometric determination of iron with DTPA in the presence of a large amount of aluminium

Potentiometric determination of iron with DTPA at pH 1.6 (platinum and calomel electrodes) permits determination of iron in the presence of aluminium up to an Al:Fe ratio of 70. Aluminium is determined indirectly by addition of excess of DCTA, adjustment to pH 5, and back-titration with iron(III) chloride.     

The Electrode Behavior and the Storing Capacity from Liver Ferritin of Dasynatis Akajei

Ferritin, a metallic protein, is a special biological large molecule that plays two central physiological functions in living cell simultaneously^[1]. In addition, the ferritin is able to express two functions having activity of H₂-uptake and exhibiting electrode behavior that picks the electrons up from a bare platinum electrode directly under anaerobic condition^[2-3]. In this paper, a direct electrochemical technology under aerobic conditions is employed to study kinetics of iron release from liver ferritin of Dasyatis akajei (DALF). Using aerobic condition, an electron tunnel across the ferritin shell plays still a critical role in taking the electrons from a bare platinum electrode for iron release without any mediator aid. Moreover, using similar condition, two reduction potentials of the ferritin core with -135 mV and -416 mV vs. NHE are measured by the technology. Unlike other processes of iron release, a kinetic study for complete iron release is confirmed to show a triphasic behavior defined as zero-order reaction. DALF is known to heme bind to generate a hemeoprotein, named DALF_h The heme function has been investigated to accelerate rate of iron release. Using similar studies, the kinetic datum indicates that the rate of iron release depends tightly on not only the reduction potential of the electrode, but also the regulation capacity of protein shell itself.     

Voltammetric determination of iron(II) and iron(III) in standard rocks and other materials

Voltammetry at a rotating platinum electrode in concentrated electrolyte solutions containing HCl and LiCl is described for simultaneous determinations of iron(II) and iron(III) in a variety of materials. Applications of the method to some U.S. Geological Survey standard rocks, a Georgian clay, and an iron-containing multiple vitamin tablet are described. For materials which can be dissolved without altering the original iron(II)/ iron(III) ratio, this method enables the two valence states to be determined rapidly and simultaneously. The technique is precise (r.s.d. ≈ 2%) and relatively free from interference, and requires only a recording d.c. polarograph.