Solubility of iron(Ⅲ) and nickel(Ⅱ) acetylacetonates in supercritical carbon dioxide

As a common precursor for supercritical CO_(2)(scCO_(2))deposition techniques,solubility data of organometallic complexes in scCO_(2)is crucial for the preparation of nanocomposites.Recently,metal acetylacetonates have shown great potential for the preparation of single-atom catalytic materials.In this study,the solubilities of iron(Ⅲ)acetylacetonate(Fe(acac)3)and nickel(Ⅱ)acetylacetonate(Ni(acac)2)were measured at the temperature from 313.15 to 333.15 K and in the pressure range of 9.5–25.2 MPa to accumulate new solubility data.Solubility was measured using a static weight loss method.The semi-empirical models proposed by Chrastil and Sung et al.were used to correlate the solubility data of Fe(acac)3 and Ni(acac)2.The equations obtained can be used to predict the solubility of the same system in the experimental range.

锑氧化菌Pseudomonas sp.AO-1的分离鉴定及其对Sb(III)的氧化性能

采用抗性筛选法从锡矿山筛选出一株锑氧化菌,并利用分子生物学技术对其进行鉴定;考察了其氧化Sb()Ⅲ的性能和氧化次生矿物的特征.结果表明:锑氧化菌属于假单胞菌属(Pseudomonas),将其命名为Pseudomonas sp.AO-1(简称:AO-1);影响AO-1氧化Sb(Ⅲ)的因素主要有溶液pH值、溶解氧和铁锰氧化物(单质铁、FeCl_(3)和MnO_(2))等;AO-1在好氧和缺氧条件下均能氧化Sb(Ⅲ),好氧氧化Sb(Ⅲ)的米门常数Km和最大氧化速率Vmax值分别为393.05µmol/L和0.271µmol/(L·min),体现了较强的锑氧化性;AO-1和铁锰氧化物的耦合作用能促进Sb(Ⅲ)的氧化,且铁锰氧化物促进AO-1氧化Sb(Ⅲ)的速率依次为:FeCl_(3)>MnO_(2)>单质铁;AO-1和铁锰氧化物耦合氧化Sb(Ⅲ)生成含Sb(Ⅴ)的次生矿物,次生矿物会加速Sb(Ⅲ)的氧化以及影响锑在环境中的迁移转化.菌株AO-1的锑氧化性能良好,对于锑的生物化学转化和土壤微生物修复的应用有重要意义.

Synthesis and Crystal Structure of Tris(N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinonato)iron(III)

The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively.

Kinetics on Thermal Decomposition of Iron(III) Complexes of 1,2-Bis(Imino-4’-Antipyrinyl)Ethane with Varying Counter Anions

A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, and Br-, has been done by thermogravimetric analysis by using Coats-Redfern equation. The kinetic parameters like activation energy (E), pre-exponential factor (A) and entropy of activation (ΔS) were quantified. On comparing the various kinetic parameters, lower activation energy was observed in second stage as compared to first thermal decomposition stage. The same trend has been observed for pre-exponential factor (A) and entropy of activation (ΔS). The present results show that the starting materials having higher activation energy (E), are more stable than the intermediate products, however;the intermediate products possess well-ordered chemical structure due to their highly negative entropy of activation (ΔS) values. The present investigation proves that the counter anions play an important role on the thermal decomposition kinetics of the complexes.

Synthesis, characterization, and stability of iron (III) complex ions possessing phenanthroline-based ligands

It has previously been demonstrated that phenanthroline-based ligands used to make gold metallotherapuetics have the ability to exhibit cytotoxicity when not coordinated to the metal center. In an effort to help assess the mechanism by which these ligands may cause tumor cell death, iron binding and removal experiments have been considered. The close linkage between cell proliferation and intracellular iron concentrations suggest that iron deprivation strategies may be a mechanism involved in inhibiting tumor cell growth. With the creation of iron (III) phen complexes, the iron binding abilities of three polypyridal ligands [1,10-phenanthroline (phen), 2,9-dimethyl-1, 10-phenanthroline (methylphen), and 2,9-di-sec-butyl-1, 10-phenanthroline (sec-butylphen)] can be tested via a competition reaction with a known iron chelator. Therefore, iron (III) complexes possessing all three ligands were synthesized. Initial mass spectrometric and infrared absorption data indicate that iron (III) tetrachloride complex ions with protonated phen ligands (RphenH+) were formed: [phenH][FeCl4], [methylphenH][FeCl4], [sec-butylphenH][FeCl4]. UV-vis spectroscopy was used to monitor the stability of the complex ions, and it was found that the sec-butylpheniron complex was more stable than the phen and methylphen analogues. This was based on the observation that free ligand was observed immediately upon the addition of EDTA to the [phenH][FeCl4] and [methylphenH] [FeCl4] complex ions.

Syrup versus Drops of Iron III Hydroxide Polymaltose in the Treatment of Iron Deficiency Anemia of Infancy

Background: Iron deficiency anemia in infants is the most common micronutrient deficiency worldwide. The main cause is low iron intake in the presence of accelerated physiologic growth rate. Objective: The current study aimed at prospectively comparing the efficacy of iron III hydroxide polymaltose syrup (IPS) versus iron III hydroxide polymaltose drops (IPD) in treating iron deficiency among infants attending the hematology outpatient clinic. Our hypothesis was that IPS would be less effective possibly related to the difficulty of giving the medication. Methods: Participants diagnosed with iron deficiency anemia between 11-24 months were randomly assigned to receive either IPS or IPD for 3 months. The main outcome parameter was hemoglobin blood level, while the secondary outcome parameters were: 1) iron;2) ferritin;3) transferrin (i.e.?total iron binding capacity);4) mean corpuscular volume;and 5) red blood cell distribution width. Results: Out of the 104 recruited infants, 55 (52%) completed the study: 29 in the IPS group and26 inthe IPD group. There was no significant difference in the main outcome parameter at either 1 or 3 months of treatment: mean hemoglobin was 10.5 versus 10.7 g/dL within a 1 month treatment, P = 0.4;mean hemoglobin was 11.0 versus 11.1 g/dL within a 3 months of treatment, P = 0.59. Likewise, no significant differences were found with respect to the occurrence of side effects. Conclusion: Oral IPD and IPS are equally effective in treating iron deficiency anemia in infants aged 11 - 24 months.

Structural Analysis of Magnesium-Aluminium Hydrotalcites Modified with Iron III Obtained by Hydroxide Precipitation Method

Hydrotalcite-type anionic clays are a group of important materials used in adsorption processes, mainly for organic pollutants removal due the layered double hydroxide structure. The layer-interlayer interactions provide a structural memory even after dehydration and dehydroxylation process, since a very stable interlayer anions are part of material composition, like the carbonate one. A limited numbers of trivalent modifier cations can replace the aluminium cation due the ionic radii mismatch or oxidation state restrictions. Transition metal cations can replace the aluminium one in octahedral site of hydroxide lamellas in order to improve the adsorptive behaviors. In this work, we have investigate three compositions of carbonated magnesium-aluminium hydrotalcite with dif-ferent iron (III) contents through the co-precipitation method at pH 11 and aging step at 60°C for 6 hours. Thermal analysis was performed aiming the determination of the hydration water and hydroxyl amounts in dried precipitate samples, taking in account the results obtained for X-ray diffractometry, infrared spectroscopy, and nitrogen adsorption-desorption characterization for several thermally treated samples. All of synthesized samples showed high surface areas, even for high temperature of thermal treatment. The co-substitution with iron (III) reduced the temperature of dehydration and dehydroxylation process, but the co-substitution at 5 mol% provides other desirables characteristics, like a more amount of rhombohedral HDL phase and higher porosity, even after the thermal treatment at 500°C for 4 hours. This result makes that composition very applicable as a reusable adsorbent material in order to removal several types of micro-pollutant compounds in aqueous media.

偶氮胭脂红B动力学光度法测定Fe(III)

A new kinetic spectrophotometric method for the determinations of iron(III) has been developed based on its catalytic effects on the oxidation reactions of azocarmine B by KIO4.Under the optimum conditions,the linear range for the determination of Fe3+ by the proposed method is 0～08μg/25ml,and the detection limit is 695×10-10g/ml.The relative standard deviation for 11 replicate determinations of 04 μg Fe(III) is 15%.The results obtained from the studies on the effects by more than 30 kinds of foreign ions indicated that the method free from most interference.The method has been applied for the determination of iron in water,human hair and food samples with relative standard deviations between 08% and 34%,and the recovery between 96% and 104%.

纳米铁用于饮用水中As(III)去除效果

主要考察实验室合成制得的纳米铁对毒性高,迁移能力强,在厌氧地下水中作为砷的主要存在形式的As(III)去除效果。通过批实验探讨吸附动力学,以及pH和纳米铁投加量对As(III)的去除影响。反应1h时,0.25g纳米铁对起始质量浓度为910μg·L-1As(III)的去除率高达99%以上;反应遵循准一级反应动力学方程,标准化后的速率常数kSA为1.64mL·m-2·min-1。研究结果表明,具有高反应活性的纳米铁将成为饮用水中砷去除非常有效的吸附材料。

电感耦合等离子体发射光谱法直接测定磷酸铁中磷含量

采用电感耦合等离子体发射光谱法,通过筛选合适的分析谱线消除共存元素干扰,实现了磷酸铁中磷含量的直接测定,磷浓度在100~500 mg/L范围内具有良好的线性关系(r≥0.9990),10次重复测定相对标准偏差(RSD)0.06%~0.49%,加标回收率在99.6%~100.9%,检出限为0.01%,能够满足实际样品的分析检测要求。

Sorption Kinetic of Arsenate as Water Contaminant on Zero Valent Iron

This study investigates the sorption of arsenate from water using zero-valent iron ZVI as sorbent. Batch experiments were carried out to study the sorption kinetics of arsenate under different concentrations of arsenate varies from 0.5 to 200 mg/l. A kinetic model was considered to describe the arsenates sorption on ZVI material. The kinetics of the arsenate sorption processes were described by the Langmuir kinetic model. The sorption capacity increases with high initial concentration which obtained the maximum sorption 2.1 mg/g at 200 mg/l of arsenate initial concentration. The results show that the rapid initial sorption rates of arsenate were occurred at the beginning of experiments running time, followed by a slower removal that gradually approaches an equilibrium condition. The data from laboratory batch experiments were used to verify the simulation results of the kinetic model resulting in good agreement between measured and modeled results. The results indicate that ZVI could be employed as sorbent materials to enhance the sorption processes and increase the removal rate of arsenate from water.

Responses of Aerobic Rice (Oryza sativa L.) to Iron Deficiency

Aerobic rice has the advantage of saving water. Most published work has focused on improving its yield, while few reported on its micronutrient status. In fact, Fe deficiency is a common nutritional problem in the production of aerobic rice. Short- term hydroponic culture experiments were conducted to study the response of aerobic rice to Fe deficiency and the effect of root exudates from Fe-deficient wheat on its Fe uptake ability. The results indicate that the amount of phytosiderophores （PS） released from aerobic rice did not increase under Fe deficient conditions. The Fe（III） reducing capacity of Fe-deficient aerobic rice did not increase and the solution pH did not decrease significantly. What＇s more, no obvious swelling was observed in the root tips. Aerobic rice did not show special responses to improve their Fe nutrition under Fe deficiency as both strategy I and II plants though they were very sensitive to Fe deficiency. This may be a reason which causes Fe deficiency problem in aerobic rice. However, root exudates from Fe-deficient wheat （PSw） could improve its Fe nutrition in the presence of insoluble Fe（OH）3. This suggests that aerobic rice could utilize Fe activated by PSw.

The reaction of the iron thiosulfate-nitrosyl complex with adenosine triphosphoric acid

Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndrome. In this work, the reaction of the TNIC with adenosine triphosphoric acid (ATP) was studied. Formation of the products for the reaction of ATP with TNIC was shown by electronic microscopy. The kinetics of the reaction was controlled by spectrofluorometric method, and the complexation constant was measured. The mechanism of interaction of ATP with TNIC was proposed, and the relevant kinetic model satisfactorily described the experimental data, which permitted to calculate the rate constants for these process stages. NMR, IR, and M?ssbauer studies were used for determination of the reaction product structure. NMR study showed TNIC interaction only with adenine part of ATP. The method of IR spectroscopy identified both the absence NO in the reaction products and the occurrence of new Fe-S and Fe-N bonds. M?ssbauer study showed that iron in the reaction products was presented by two forms: Fe(II) and Fe(III). Thus, the structures for the [ATP-Fe2+S] and [ATP-Fe3+S] complexes were proposed.

A new method for quantification of total polyphenol content in medicinal plants based on the reduction of Fe(III)/1,10-phenanthroline complexes

This paper proposes an alternative analytical spectrophotometric method for the total polyphenol quantification in the aqueous extract of plants. When these extracts are added to solutions of Fe(III), in presence of 1,10-phenanthroline, the absorbance values at 551 nm (A511nm) due to the complexes formed are proportional to the total polyphenol concentration expressed as pyrogallic acid (PA). A typical calibration graph of A511nm values vs. PA is linear from 0.16 to 0.64 mg L-1 (r = 0.994, n = 6) with a limit of detection 0.041 mg L-1. The results of the polyphenol content of the aqueous extracts of twenty medicinal Brazilian plants obtained with the proposed method were compared with values using the Folin-Ciocalteu reagent. A paired t-test revealed no statistically significant difference for the species analyzed. The total antioxidant capacity of the same twenty extracts was determined based on the scavenging of stable radical DPPH.

基于Fe(Ⅲ)和邻苯二胺显色反应快速检测硫化物

比较了不同金属离子(Fe^(2+)、Fe^(3+)、Cu^(2+)、Zn^(2+)、Al^(3+)、Na^(+)、Ca^(2+)、Mg^(2+)、K^(+)、Ag^(+)、Cr^(3+))对邻苯二胺(OPD)的氧化能力,基于Fe^(3+)能直接氧化OPD产生黄色发荧光的产物而构建了Fe^(3+)-OPD显色体系。结合硫化物的还原性以及对金属离子较强的亲和性,开发了一种通过比色法选择性检测硫化物的方法。结果表明,在pH 4.0NaAc-HAc缓冲液中,Fe^(3+)-OPD显色体系的吸光度和荧光强度与NaHS的浓度分别在10~200μmol/L和5~150μmol/L范围内呈线性关系,荧光法的检出限可达0.1μmol/L,体系内其他还原性物质及硫醇对NaHS的检测无干扰。将Fe^(3+)-OPD显色体系结合纸芯片构建的纸基比色体系蓝色分析色道值(B值)与NaHS的浓度在20~150μmol/L范围内呈线性关系,检出限为2μmol/L,并可用于定量检测加标自来水和胎牛血清中的硫化物。

铜冶炼企业生产废水除氟工艺实践研究

以某铜冶炼企业生产废水为研究对象,采用聚合硫酸铁协同硫酸铝对生产废水进行除氟试验。根据试验结果表明,在低砷废水(砷含量小于1mg/L)中氟含量小于30mg/L条件下,废水与一定量的聚合硫酸铁、硫酸铝、PAM、熟石灰(聚合硫酸铁添加量为0.1g/L,硫酸铝添加量为2~3g/L)反应并将溶液的pH值调整至在6~8的之间时,反应后的废水中氟<5mg/l,低于回用水标准,砷含量可以降低至0.5mg/L以内,能够满足GB 25467—2010《铜、钴、镍工业污染物排放标准》。

以磷铁为原料水热法制备电池级磷酸铁的研究

以黄磷所得副产品磷铁为原料,通过湿法溶解、除杂、结晶等工艺制备电池级磷酸铁,然后利用制备出的磷酸铁制备磷酸铁锂。制备电池级磷酸铁的最佳工艺参数为:硝酸浓度为3.0 mol/L、最佳反应温度为110℃、最佳反应时间为120 min、反应体系铁质量浓度为18.0 g/L,此时样品中铁含量与铁磷比接近理论值。LiFePO_(4)/C样品首次充电容量、放电容量、放电的库伦效率分别为158.8 mAh/g、147.8 Ah/g、93.1%,说明磷酸铁锂电化学性能较好,能用于锂电池的正极材料。

利用实验室废硫酸制备聚合硫酸铁及处理效果的研究

实验室每年都会产生较多的废硫酸,废硫酸的处理也会产生不少的费用,储存在实验室也会产生安全隐患,本文主要研究利用实验室废硫酸与工业硫酸按照一定比例混合采用氯酸钠氧化法来制备聚合硫酸铁,将废硫酸加以利用变废为宝,不但对环境没有影响而且将废硫酸变成了净水剂,达到了以废治废的目的。自制聚合硫酸铁通过检测分析Fe^(3+),盐基度,Fe^(2+)等指标来判断自制聚合硫酸铁的可行性,结果显示检测指标均可满足国家对聚合硫酸铁生产的各项要求。通过应用自制聚合硫酸铁与市售聚合硫酸铁对污水的处理效果的各项指标来对比分析自制聚合硫酸铁对污水处理效果的可行性。结果显示:自制聚合硫酸铁与市售聚合硫酸铁对污水处理的各项指标的去除率基本相同,对污水的处理效果是一样的。

流动注射-多道检测-催化动力学同时测定铜和铁

基于Cu(Ⅱ),Fe(Ⅲ)在pH3～9范围内能同时催化过氧化氢氧化罗丹明B的褪色反应,探讨了最佳反应条件,通过构建流动注射pH梯度,采用CCD-二极管阵列检测器检测吸光度差值,反向传播-人工神经网络(BP-ANN)处理数据,实现了Cu(Ⅱ),Fe(Ⅲ)流动注射-催化动力学光度法的同时测定。Cu(Ⅱ)和Fe(Ⅲ)的检出限分别为0.10和0.21μg·L^(-1),采样频率为10次·h^(-1),本法用于标准参考物质和食品样品中铜、铁的同时测定,结果满意。

β-环糊精构筑氨基酸氧化酶的研究

报道了用β-环糊精二间羧基苯磺酸酯与三氯化铁形成的配合物构筑模拟氨基酸氧化酶,将苯丙氨酸氧化脱氨生成苯丙酮酸,在过量H_2O_2的存在下,苯丙酮酸进一步被氧化脱羧生成苯乙酸,若此反应体系是在N,N-二甲基甲酰胺(以下缩写DMF)的弱碱性条件下。