钢大气腐蚀锈层的红外、拉曼光谱研究

运用红外光谱、拉曼光谱分析的方法,对碳钢A₃和低合金钢10CrMoAl经青岛大气腐蚀的锈层样品,进行了比较测试,综合分析得出锈层中主要组成物相为α-Fe₂O₃,γ-FeOOH, α-FeOOH, δ-FeOOH,Fe₃O₄,以及各组成物相相对含量随腐蚀时间的变化情况。     

氧化铁还原率及金属化率的测量新方法

用H₂及CO还原氧化铁过程中,使用了X-ray粉末衍射和化学分析方法确定了氧化铁及金属铁的定量分析关系。铁素体(α_Fe)、奥氏体(γ_Fe)、碳化铁(Fe₃C)、磁铁矿(Fe₃O₄)、赤铁矿(Fe₂O₃)与浮氏体(Fe_0.947O)的摩尔强度定量关系的系数分别为0.56,0.56,0.52,0.87和2.57。通过这些系数,可以计算出氧化铁的金属化率和还原率。     

3-甲基-1-乙酰基-5-(2-羟基苯基)-4,5-二氢吡唑及其铕和铽配合物的合成与光谱学研究

以六水合硝酸铽和六水合硝酸铕,3-甲基-1-乙酰基-5-(2-羟基苯基)-4,5-二氢吡唑(HL),1,10-邻菲罗啉和三苯基氧磷(TPPO)合成了TbL₃·2H₂O,TbL₂(phen)·H₂O,TbL₂(TPPO),EuL₃·2H₂O,EuL₂(phen)·2H₂O,EuL₂(TPPO)·2H2O 6个固体配合物。用元素分析,红外光谱,荧光光谱对配合物进行了组分确定和结构表征。IR表明,自由配体HL与稀土离子配位后,位于1644 cm-1处的ν_CC发生移动,相应的ν_CN振动吸收峰降到了1 600 cm-1,结合元素分析等其他表征说明HL和稀土离子发生配位。室温下测定了配合物的荧光激发光谱和发射光谱,激发光谱表明配合物EuL₂(Phen)·2H₂O和TbL₂(Phen)·H₂O的最佳激发波长分别为310和320 nm, 在此激发波长下扫描发射光谱,EuL₂(Phen)·2H₂O和TbL₂(Phen)·H₂O相对荧光强度最强,第二配体phen对Eu3+和Tb3+离子的荧光发射强度有明显的增强作用。     

三种具有Keggin结构的硅钨氧簇化合物的光谱研究

合成了三种具有Keggin结构的硅钨氧簇化合物：K₃H[SiWⅥ₁₂O₄₀]·3H₂O(Ⅰ),(H₃O)₄[H₃SiWⅥ₉WⅤ₃O₄₀]·2H₂O(Ⅱ)和[(CH₃)₄N]₄[SiWⅥ₁₂O₄₀]·4.5 H₂O(Ⅲ),用FTIR,NIR FT-Raman,UV-Vis和荧光光谱等研究手段进行了光谱研究,探讨其结构与性能的关系。在这些化合物中, 阴离子相同或类似,具有孤立的[SiW₁₂O₄₀]簇骼基元,通过静电作用和弱的氢键与阳离子及水相连。它们的FTIR和NIR FT-Raman光谱研究表明：硅钨酸盐的特征振动频率与其结构相关,由于化合物Ⅱ中的部分W6+已被还原成W5+,使ν_as(WO_d)振动频率降低,且簇阴离子电荷大小也明显地对ν_as(W—O_c—W),ν_as(Si—O_a),δ(O_a—Si—O_a)等产生影响;化合物Ⅰ和Ⅱ的UV-Vis光谱显示,在200和250 nm左右有紫外吸收谱带;化合物Ⅰ的稳态荧光光谱观察到分别以220,350和440 nm激发时,相应在350,440和520及675 nm左右产生一个或两个发射峰。     

呋喃甲酰基吡唑啉酮缩氨基硫脲配合物的合成、光谱表征及生物活性

合成了含硫席夫碱试剂1-苯基-3-甲基-4-(α-呋喃甲酰基)吡唑啉酮-5缩氨基硫脲(HL)及其Zn(Ⅱ),Cd(Ⅱ),Co(Ⅱ)配合物。元素分析及摩尔电导值表明新配合物的组成为[ZnL₂]·1.5H₂O,[CdL₂]·C₂H₅OH和[CoL₂]·H₂O。运用红外光谱、紫外光谱、核磁共振谱和磁矩, 对配合物进行了表征。抗菌实验表明配合物具有较强的抗菌生物活性。     

氯柱硼镁石在硼酸溶液中溶解转化的Raman光谱

利用Raman光谱对氯柱硼镁石在30 ℃时,4.5%的硼酸水溶液中溶解相转化过程进行了研究。研究结果表明相转化产物为库水硼镁石(2MgO·3B₂O₃·15H₂O)。根据Raman光谱位移对溶液中各种聚硼酸根B(OH)-₄,B₂O(OH)2-₆,B₃O₃(OH)-₄等阴离子的Raman峰进行了归属以及它们间的相互作用分别进行了讨论分析。提出了溶液中硼氧配阴离子的存在形式及其相互作用机理和我国青藏高原盐湖区库水硼镁石形成的地球化学成盐条件和机理。     

两种含铋的杂多化合物的光谱研究

在水热条件下合成了两个含铋的杂多化合物：Co₅[Bi₂Co₂W₂₀O₇₀(H2O)₆]·44H₂O(Ⅰ)和Na₃H₂[Ce₃(H₂O)₁₈Bi₂W₂₂O₇₆]·23H₂O(Ⅱ),通过用FTIR, NIR FT-Raman和UV-Vis DRS光谱研究了它们的结构和性能的关系。ν_as(MO_d)和ν_s(M—Ob—M)的特征振动频率和材料的结构相关。ν_as(M—O_b—M)振动频率可说明当W原子被Co原子取代时氧化活性增强。在化合物Ⅰ和Ⅱ的UV-Vis DRS谱中,分别存在254,319和220,310 nm的(O_d→W),(O_b, c→W)的荷移跃迁特征峰,化合物Ⅰ还在529 nm处出现宽而弱的Co2+的d-d跃迁吸收谱带。最后,文章还对化合物Ⅰ进行了量子化学计算,用于说明其结构特征。     

对氨基马尿酸铽二元、三元配合物的合成、表征及荧光光谱研究

在乙醇溶液中以邻菲咯啉(phen)、2,2’-联吡啶(bipy)和对氨基马尿酸(PAH,HL)为配体与铽离子(Tb(Ⅲ))合成了二元和三元稀土配合物。通过元素分析、差热-热重分析、紫外光谱、红外光谱分析,确定了配合物的组成为TbL₃(1)、TbL₃·phen·H₂O(2)和TbL₃·bipy·H₂O(3),并讨论了配合物1～3的谱学性质和荧光性能。推测出羧基中的氧原子以桥式双齿的形式与稀土离子配位。由红外光谱和热分析测试确定的配合物1及配合物2中的水分子未参与配位。研究表明,铽配合物在489,583和621 nm处出现发射峰,它们分别归属于5D₄→7F₆,5D₄→7F₅,5D₄→7F₄和5D₄→7F₃的跃迁。其中544 nm处5D₄→7F₅跃迁的强度最强,配体的共平面性和共轭性越大,配合物的荧光性能越高,三元配合物TbL₃·phen·H₂O和TbL₃·bipy·H₂O的荧光强度优于二元配合物TbL₃的荧光强度。     

绿松石的激光拉曼光谱研究

对湖北、安徽地区绿松石进行了激光拉曼光谱测试分析。结果表明,绿松石中H₂O,OH-及PO3-₄的基团振动是导致其激光拉曼光谱形成的主要原因。3 510～3 440 cm-1的谱峰是由ν(OH)伸缩振动所致,其中ν(OH)振动导致的强拉曼特征谱峰在3 470 cm-1附近,ν(H₂O)伸缩振动致拉曼谱峰位于3 290～3 070 cm-1附近的较为宽缓的弱谱峰处;由ν₃(PO₄)伸缩振动致强拉曼特征谱峰在1 200～1 030 cm-1之间,其中ν₃(PO₄)振动导致的强拉曼特征谱峰在1 039 cm-1附近,ν₄(PO₄)弯曲振动位于650～540 cm-1范围,ν₂(PO₄)的弯曲振动谱峰位于500～410 cm-1处;不同产地、不同结晶类型的绿松石表现出的拉曼谱峰特征基本一致。     

氧氟沙星的荧光光谱与质子化作用研究

研究了氧氟沙星(Ofloxacin,OFL)在不同pH条件下的荧光光谱、紫外光谱和质子化作用。在强酸性溶液中,OFL分子可以结合两个质子而以三元酸H₃L2+的形式存在,最大荧光发射波长(λ_max)为505 nm。随着pH值升高,OFL的荧光光谱发生变化,在激发光谱中352 nm 形成一等荧光点,同时在紫外吸收光谱中出现等色点,这一光谱特征表明H₃L2+逐渐失去4位C羰基氧结合的质子。在pH 2.5～4范围内,OFL以H₂L+形式存在,λ_max为499 nm。当pH＞4时,随pH值升高,位于499 nm 的荧光发射峰逐渐蓝移至455 nm,在484 nm形成一等荧光发射点,表明C-3位羧基质子的离解。在pH 7左右,OFL以双极离子HL形式存在,λ_max为455 nm,是最强的荧光型体。当pH＞8时,随pH值升高,λ_max由455 nm红移至约475 nm,同时荧光强度下降,表明HL失去哌嗪环N-4上结合的质子。当pH＞10时,OFL以阴离子L-形式存在, 荧光强度随pH值升高而降低,但λmax基本不变,表明介质环境对OFL的荧光性质有一定影响。     

Analysis of the Products from the Reaction of L-Cysteine with Fe(III) Compounds in Acidic Medium

Journal of Applied Spectroscopy - The reaction of L-cysteine solution with the iron(III) compounds FeCl3, Fe2(SO4)3, and Fe(NO3)3 in an acidic medium (pH 2) was studied. The reaction was complete...     

Density functional theory study of water adsorption on FeOOH surfaces

Using density functional theory (DFT) calculations with an on-site Coulomb repulsion term, we study the composition, stability, and electronic properties of the most common FeOOH surfaces goethite(101), akaganeite(100), and lepidocrocite(010), and their interaction with water. Despite the differences in surface structure, the trends in surface stability of these FeOOH polymorphs exhibit remarkable similarities. We find that the reactivity and the binding configuration of adsorbates depend strongly on the coordination of surface iron: at the fourfold coordinated Fe2 site water is chemisorbed, whereas at the fivefold coordinated Fe1 water is only loosely bound with hydrogen pointing towards the surface. Our results show that the oxidation state of surface iron can be controlled by the surface termination where ferryl (Fe^4 +) species emerge for oxygen terminated surfaces and ferrous iron (Fe^2 +) at iron and water terminations leading to a reduced band gap. In contrast, the fully hydroxylated surfaces, identified as stable surface configurations at standard conditions from the surface phase diagram, show electronic properties and band gaps closest to bulk FeOOH with ferric surface iron (Fe^3 +). Only in the case of goethite(101), a termination with mixed surface hydroxyl and aquo groups is stabilized.     

铁的氢氧化合物稳定相α, β-FeOOH的表征及光谱分析

铁的氢氧化合物稳定相针铁矿(α-FeOOH)及四方纤铁矿(β-FeOOH)的合成材料因具有纳米颗粒粒径、较高比表面积,在工业生产和环境治理中被广泛应用。α,β-FeOOH作为重金属等污染物的吸附材料尤受关注。但其合成过程中溶液pH值和反应条件(如不同温度下加热或室温磁力搅拌等)对α,β-FeOOH矿物材料晶型、颗粒形貌、尺寸和界面特性的影响及其与矿物环境功能的相关性报道较少。故本工作基于Fe(NO₃)₃和FeCl₃溶液在一定pH值范围内分别易于形成α-FeOOH和β-FeOOH稳定相,利用X射线衍射仪、透射/扫描电子显微镜和激光粒度分析仪对加热(40和70 ℃)和磁力搅拌(25 ℃)条件下形成的矿物α, β-FeOOH的晶型和颗粒形貌结构进行了鉴定与表征,同时利用红外光谱仪测定了矿物表面的特征结构基团。研究结果表明,40和70 ℃反应温度下形成的矿物Aka-T40, Aka-T70, Gth-T70具有颗粒均一、结晶型较好、比表面积较大等特性,是良好的去除环境污染物的吸附剂材料。     

Raman spectroscopic studies of the corrosion of model iron electrodes in sodium chloride solution

We have explored the un‐enhanced Raman spectra of both single and twin electrodes in 3.5% NaCl solution (at ambient temperatures) over a range of applied potentials (between 20 and 200 mV) and times (between 0 and 5 h). Under these conditions, we observed the initial formation of ‘green rust’ (hydroxychlorides and/or hydroxycarbonates), followed by the formation of magnetite (Fe₃O₄) and then a mixture of the α‐ and γ‐FeOOH (goethite and lepidocrocite, respectively). These data are consistent with a model for corrosion during which the initially formed magnetite is either covered, or replaced, by layers of the FeOOH oxidation products. Fitting of the data as a function of time and potential shows that, although the product range is independent of potential, the relative kinetics of formation of magnetite and its subsequent conversion to the γ‐FeOOH were potential and time dependent. Analysis by mapping of the dry corroded surface showed a variety of species, including green rust, some Fe(OH)₃, as well as the γ‐FeOOH, and possibly some β‐FeOOH. But no surface magnetite was found, indicating that this material had been either covered up or converted to FeOOH. We noted several complications during this work, including the interference of resonance effects (on the Raman intensities) and the heterogeneity of the corrosion process (and hence distribution of species on the corroded surface). However, we believe that the use of un‐enhanced Raman methods has led to conclusions more likely to be relevant to ‘real’ corrosion processes. Copyright © 2007 John Wiley & Sons, Ltd.     

Superparamagnetic behaviour of goethite prepared in sulphated medium

The formation of goethite is simulated by stirring up in the presence of air a mixture of FeSO₄, 7H₂O and NaOH in the 1∶5 ratio at different initial concentrationC of ferrous ions. Mössbauer spectra of the oxidation end products display the sextet of goethite (αFeOOH) and a paramagnetic ferric doublet increasing whenC decreases; the crystal structure of goethite is also being modified. At a critical low concentration, the orthorhombic structure is no longer justified; inactive α′-FeOOH, which has a similar X-ray diffraction pattern as δ-FeOOH is obtained. All these compounds are crystallographically related.     

Role of pH and calcium ions in the adsorption of an alkyl N-aminodimethylphosphonate on steel: An XPS study

The role of pH and calcium ions in the adsorption of an alkyl N-aminodimethylphosphonate on mild steel (E24) surfaces was investigated by XPS. Fe 2p_3/2 and O 1s spectra show that the oxide/hydroxide layer developed on the steel surface, immersed in the diphosphonate solution (7 ≤ pH ≤ 13, without Ca²⁺) or in a filtered cement solution (pH 13, 15.38 mmol l⁻¹ of Ca²⁺), consists of Fe₂O₃, covered by a very thin layer of FeOOH (goethite). The total thickness of the oxide/hydroxide layer is ∼3 nm and is independent of the pH and the presence/absence of Ca²⁺. In the absence of Ca²⁺ ions, the N 1s and P 2p spectra reveal that the adsorption of the diphosphonate on the outer layer of FeOOH takes place only for pH lower than the zero charge pH of goethite (7.55). At pH 7, the adsorbed diphosphonate layer is continuous and its equivalent thickness is ∼24 Å (monolayer). In the presence of Ca²⁺ ions, the C 1s and Ca 2p signals indicate that calcium is present on the steel surface as calcium phosphonate (and Ca(OH)₂, in very small amount). The adsorption of the diphosphonate molecules on the steel surface is promoted in alkaline solution (pH > 7.55) by the doubly charged Ca²⁺ ions that bridge the O⁻ of goethite and the P-O⁻ groups of the diphosphonate molecules. The measured values for the Ca/P intensity ratio are in the range 0.75-1, which suggests that the diphosphonate molecules are adsorbed on steel forming a polymer cross-linked by calcium ions through their phosphono groups. In the presence of Ca²⁺ ions in alkaline solution, the adsorbed diphosphonate layer is discontinuous and the surface coverage is found to be ∼34%.     

光度法研究聚乙二醇-硫酸铵-邻苯三酚红体系中铋(Ⅲ), 铁(Ⅲ), 铜(Ⅱ), 镍(Ⅱ), 钴(Ⅱ), 铅(Ⅱ)的萃取分离

本文研究了在聚乙二醇(PEG)-硫酸铵[(NH_4)_2SO_4]-邻苯三酚红(PR)体系中Bi(Ⅲ),Fe(Ⅲ),Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ),Pb(Ⅱ)的萃取行为。实验结果表明,Bi(Ⅲ)在pH3.5～6.5及Fe(Ⅲ)在pH4.0～7.0范围内可以被PEG相几乎完全萃取,而Cu(Ⅱ),Co(Ⅱ)在pH1.0～7.0,Pb(Ⅱ)在pH2.0～7.0,Ni(Ⅱ)在pH1.0～4.5则不被萃取。从而实现了将Bi(Ⅲ)(pH3.5),Fe(Ⅲ)(pH5.0)与Cu(Ⅱ),Co(Ⅱ),Pb(Ⅱ),Ni(Ⅱ)混合离子的定量分离。同时探讨了PEG相的萃取机理。     

离子色谱法测定清洗液废酸中的4种阴离子

介绍了清洗液废酸中F-、Cl-、SO42-和NO3-的测定方法,通过一定的前处理,减少清洗液废酸中金属离子及残留酸液的干扰,有效去除了对色谱柱带来的污染。利用优化的实验条件,准确测定了清洗液废酸中F-、Cl-、SO42-和NO3-的含量,检出限分别为0.04、0.09、0.71、0.27mg/L,回收率为94%—109%。     

Fluctuations of magnetic moments in fine particles: SEDM studies

The spectra of γ-quanta resonantly scattered on the nuclei⁵⁷Fe contained in the goethite FeOOH microparticles reveal the presence of energetically shifted (satellite) component that arises due to the repopulation of hf sublevels during the lifetime of excited nuclear state. This observation confirms the hypothesis of relaxation behaviour of magnetic moments in microcrystalline goethite.     

CuCl_2-H_2O体系和FeCl_3-H_2O体系络合物拉曼光谱研究与溶液拉曼定量分析探索

详细研究了CuCl2-H2O体系和FeCl3-H2O体系络合物拉曼峰。对于CuCl2-H2O体系,认为286cm-1峰可能是[CuCl4]2-和[CuCl6]4-等Cu2+和Cl-形成的各种形式络合物的特征峰叠加的结果,412 cm-1峰可能是以[Cu(H2O)4]2+和[Cu(H2O)6]2+为主的Cu2+的水合物的特征峰叠加在一起形成的;通过对特征峰参数的分析得到了286和412 cm-1特征峰的强度与3 400 cm-1左右水的O—H伸缩振动最强峰强度之比(I1/I3 400和I2/I3 400)以及这两个特征峰的积分面积(A1和A2)和浓度的定量关系曲线,从络合物角度实现了对CuCl2溶液的定量分析。对于FeCl3-H2O体系认为173和331 cm-1两个特征峰可能都是归属于FeCl3在水溶液中最常见的络合形式—[FeCl4]-,173 cm-1峰形很宽可能是由于Fe3+和Cl-形成的其他各种形式络合物,如[FeCl]2+,[FeCl2]+等的特征峰叠加的结果,331 cm-1之后的弱宽峰可能是以[Fe(H2O)4]3+,[Fe(H2O)6]3+为主的Fe3+的水合物的特征峰叠加在一起而形成的;通过...