(1,5-环辛二烯)氯化钌(II)多聚体的合成及表征

在无水乙醇介质中,将水合三氯化钌与1,5-环辛二烯加热回流,一步合成了(1,5-环辛二烯)氯化钌(II)多聚体[Ru(cod)Cl2]n,产率96%。用元素分析、核磁共振(¹H-NMR、¹³C-NMR)和红外光谱(IR)等分析表明产物为目标化合物。     

1,5-环辛二烯(乙酰丙酮)铱(Ⅰ)的合成及结构表征

在四氢呋喃介质中,将1,5-环辛二烯氯化铱(Ⅰ)二聚体([Ir(cod)Cl]_2)与乙酰丙酮加热回流,一步合成了1,5-环辛二烯(乙酰丙酮)铱(Ⅰ)[Ir(acac)(cod)],产率88.6%。用元素分析、红外光谱(IR)和核磁共振(~1H-NMR、~(13)C-NMR)等分析,结果表明产物为目标化合物。     

Rh(I)中间体及抗高血压药物用手性催化剂的合成及性能研究

在微压状态下,以95%的乙醇为溶剂,三氯化铑、乙烯等为原料,合成了Rh(I)中间体,产率85%;再以该中间体、1,5-环辛二烯、四氟硼酸银和(+)-1,2-双((2S,5S)-2,5-二甲基膦基)苯为原料,四氢呋喃为溶剂合成了Rh(I)手性催化剂,产率91.09%。采用元素分析、¹H-NMR、¹³C-NMR、MS-ESI⁺和IR对其化学结构进行了表征。以合成抗高血压药物雷米普利为反应模型进行催化活性评价,结果表明,该手性催化剂与商业对照品的催化活性相当,转化率≥70%,产品光学纯度≥98%。     

(1,5-环辛二烯)氯铑二聚体的合成、表征及制备工艺优化

合成了(1,5-环辛二烯)氯铑二聚体([Rh(cod)Cl]2)，用元素分析、红外吸收光谱、X射线单晶衍射仪(XRD)对其结构进行了表征，并用热重-差热(TG-TDA)分析测试其热分解特性。结果表明，该化合物为单斜晶系，P21/n空间群，晶胞参数为:a=0.72848(4) nm，b=2.51434(14) nm，c=0.88794(5) nm，β=91.0450(10)°，V=1.62612(16) nm³，R1=0.0235，wR2=0.0580，为一种同核双金属氯桥连化合物。TG-DTA测试显示该化合物分解峰出现在225℃。     

铱的氯桥双核配合物作为均相催化剂在有机合成中的应用

铱的氯桥双核配合物—1,5-环辛二烯氯化铱二聚体[Ir(COD)Cl]2由于具有独特的催化性质,已作为均相催化剂,广泛应用于各类有机合成反应进行重要药品和精细化工产品的制备。这些反应包括烷基化反应,氢化反应,氧化反应及环加成反应。[Ir(COD)Cl]2催化剂具有适用底物范围广、原料易得,对映选择性高的优点。本文对[Ir(COD)Cl]2催化的反应类型、应用和相关的反应机理进行介绍和总结。     

Ir(mpiq)2(tmd)的合成、表征及光物理性能研究

以2-(3,5-二甲苯基)异喹啉(mpiq)作为环金属配体，2,2,6,6-四甲基庚二酮(tmd)为辅助配体合成了红光铱配合物Ir(mpiq)2(tmd)，产率91.4%。采用元素分析、核磁共振谱、质谱、红外光谱及单晶X射线衍射表征了分子结构，采用紫外-可见吸收光谱和光致发光光谱研究了它的光物理性能。结果表明，该配合物呈稍微扭曲的六配位八面体配合物，为单斜晶系，C2/c空间群。在室温下最大发射波长为632 nm，为深红光发射铱磷光配合物。     

一种新型三氮唑铱(Ⅲ)配合物的合成和表征

以5-(4-氟苯基)-1,3-二甲基-1H-1,2,4-三唑(fdpt)为环金属配体、乙酰丙酮(Hacac)为辅助配体合成出一种新型铱(Ⅲ)配合物Ir(fdpt)2(acac)。采用元素分析、红外光谱、核磁共振谱分析和单晶X衍射对其组成和化学结构进行了表征。结果表明,该配合物化学组成为C25H25F2IrN6O2,属于单斜晶系,P21/c空间群。晶胞参数为a=1.58917(14) nm,b=1.64798(15) nm,c=1.06146(9) nm,β=94.741(3)°,V=2.7704(4) nm³,Z=4。     

顺式-二氯[(1R,2R)-(-)-环己二胺]合铂(Ⅱ)的合成与结构表征

顺式-二氯[(1R,2R)-(-)-环己二胺]合铂是一种铂类抗癌药物及一种合成药效基团为(1R,2R)-(-)-环己二胺的铂类抗癌药物的中间体。通过两种常规方法合成了顺式-二氯[(1R,2R)-(-)-环己二胺]合铂,产率均高达90%以上,并采用元素分析、核磁共振谱、红外光谱及X-射线单晶衍射分析对其进行了结构表征。结果表明:此化合物的单晶结构含有1分子结晶水,为单斜晶系,C2空间群,晶胞参数为:a=12.753(3) nm,b=6.8749(16) nm,c=12.325(3) nm,α=90°,β=97.577(3)°,γ= 90°,V = 1071.1(4) nm³,Z=4,Pt-N键长分别为2.047和2.027 nm,Pt-Cl键长分别为2.326和2.330 nm,且Pt²⁺、N和Cl不在同一平面上,可能与结晶水、两个交错排列的分子间N-H...Cl氢键的存在有关。     

对伞花烃二氯化钌(II)二聚体的合成及表征

采用无氧Schlenk真空技术,在无水乙醇介质中,将水合三氯化钌与α-水芹烯加热回流,一步合成了对伞花烃二氯化钌(II)二聚体([Ru(p-cymene)Cl2]2)化合物,产率93.8%,用溶剂缓慢挥发法培养出单晶。元素分析、质谱(MS)、核磁共振(¹H-NMR、¹³C-NMR)和红外光谱(IR)等分析表明产物为目标化合物;X射线单晶衍射仪表征获得的晶体结构参数表明,该化合物为正交晶系、Fdd2空间群,[Ru(p-cymene)Cl2]2为二聚体化合物。     

醋酸铑的高效液相色谱分析

二价醋酸铑为有机配合物，具有多种工业用途。建立了用高效液相色谱(HPLC)分析醋酸铑纯度的方法。最佳色谱条件为:使用C18色谱柱(φ4.6 mm×250 mm, 5 μm)，流动相为甲醇:水(pH=3)=30:70(V/V)，流速1 mL/min，柱温为25 ℃，检测波长为230 nm，进样量为10 μL。方法的线性范围为0.10~2.00 mg/mL，相关系数r=0.9997；平均回收率为100.25%，RSD=0.91%(n=3)。     

Influence of metal ions on the formation of artificial zinc rusts

The artificial rust particles were prepared from ZnCl₂ solutions dissolving Al(III), Fe(III), Fe(II), Ni(II), Co(II) and Mg(II) at different atomic ratios from 0 to 0.3 in metal/Zn. With increasing metal/Zn the crystal phases of the products turned following as ZnO → a mixture of ZnO and Zn₅(OH)₈Cl₂ · H₂O (ZHC) → ZHC. Al(III) most facilitated the formation of ZHC but Mg(II) and Fe(III) produced no ZHC. The morphology of the formed particles varied following as agglomerate → fine → rod → sheet → irregular with the increase of metal/Zn. The sheet and irregularly shaped particles were identified as ZHC and the other particles as ZnO.     

NiAl－Fe金属间化合物合金的正电子寿命谱

测量了塑性金属间化合物合金Ｎｉ（５０）Ａｌ（３０）Ｆｅ（２０），Ｎｉ（５０）Ａｌ（２０）Ｆｅ（３０）和Ｎｉ（６０）Ａｌ（２０）Ｆｅ（２０）单晶和多晶的正电子寿命谱．基于正电子寿命谱的特征参数引入了正电子双区域捕获模型，并讨论了这些合金微观结构与力学性能之间的关系．     

NiAl—Fe金属间化合物合金的正电子寿命谱

测量了塑性金属间化合物合金Ｎｉ５０Ａｌ３０Ｆｅ２０，Ｎｉ５０Ａｌ２０Ｆｅ３０，Ｎｉ６０Ａｌ２０Ｆｅ２０单晶和多晶的正电子寿命谱。基于正电子寿命谱的特征参数引入了正电子双区域捕获模型，并讨论了这些合金微观结构与力学性能之间的关系。     

Effect of dislocation density on the low temperature aging behavior of an ultra low carbon bake hardening steel

Strain aging was studied in an ultra low carbon (ULC) steel with a total carbon content of 20 ppm (wt.%) in order to identify the process stages and mechanism of bake hardening in this type of steel. The effects of dislocation density, varied by means of uniaxial tensile prestraining (1–10%) on the aging kinetics were investigated within an aging temperature range of 50–170°C. The aging was evaluated by means of strength measurements and the determination of interstitial carbon content after aging using a piezoelectric composite oscillator operating at 40 kHz. The interaction between interstitial carbon and dislocations was examined through amplitude dependent internal friction measurements. The influence of dislocation density on the aging behavior have been discussed with reference to the kinetics and mechanism of the aging process.     

Effect of solution heat treatment on galvanic coupling between intermetallics and matrix in AA7075-T6

Susceptibility to localised corrosion is strongly affected by heat treatments performed on Al-Zn-Cu-Mg alloys. In order to study how galvanic coupling between intermetallics and matrix is affected by solution heat treatment, AA7075-T6 and solution heat treated AA7075 have been characterised by means of scanning electron microscopy and scanning Kelvin probe force microscopy. Solution heat treatment strongly increased the Volta potential difference between the intermetallics and the surrounding matrix showing a strong increase in galvanic coupling. This is explained by Zn and Mg enrichment of the matrix caused by dissolution of strengthening particles during solution heat treatment.     

Characterizing corrosion behavior under atmospheric conditions using electrochemical techniques

AC and DC electrochemical experiments were performed as a function of humidity and contaminant concentration in an effort to identify the range of atmospheric environments where corrosion processes could be detected and possibly quantified. AC measurements exhibited two time constants at 25% relative humidity (RH), possibly indicating the ability to resolve both electrolyte resistance and interfacial impedance. Galvanic current measurements were sensitive to the presence of Cl_2(g) at 30% RH and electrochemical transients were detected at both 30% and 50% RH levels, also indicating sensitivity to interfacial processes. Higher humidity levels allowed better quantification due to decreasing electrolyte and interfacial impedances.     

A study on the deactivation of an IrO2–Ta2O5 coated titanium anode

The deactivation of an IrO₂–Ta₂O₅ coated titanium anode was studied during an accelerated life test at 2 A cm⁻² in 1 mol dm⁻³ H₂SO₄ solution using CV, EIS, SEM and EDX. The changes of voltammetric charge, double layer capacitance, oxide film resistance and charge transfer resistance of oxygen evolution with time during the electrolysis were monitored. The morphology and surface composition of the oxide anode before and after electrolysis test were analysed. A comprehensive process of deactivation of the oxide anode was proposed based on the test results and analysis.     

Electrochemical behaviour of amorphous and nanoquasicrystalline Zr-Pd and Zr-Pt alloys in different environments

The corrosion behaviour of melt spun amorphous and nanoquasicrystalline Zr₇₀Pd₃₀ and Zr₈₀Pt₂₀ alloy ribbons has been investigated using potentiodynamic polarization study in NaCl, H₂SO₄ and NaOH solutions at different concentrations. The amorphous and nanoquasicrystalline alloys show better corrosion resistance than Zr in all the solutions studied. Both the alloys are susceptible to chloride attack and pitting has been observed. Complete passivation has been observed in H₂SO₄, while gradual break down of passivating layer occurs in NaOH. In general, nanoquasicrystalline state in both the alloys shows better corrosion resistance than amorphous state in all the solutions studied.     

Corrosion behaviour of powder metallurgical and cast Al-Zn-Mg base alloys

The behaviour of Al-Zn-Mg base alloys produced by powder metallurgy and casting has been studied using potentiodynamic polarisation in 0.3% and 3% NaCl solutions. The influence of alloy production route on microstructure has been examined by scanning electron microscopy, Auger electron spectroscopy and secondary ion mass spectrometry. An improvement in performance of powder metallurgy (PM) materials, compared with the cast alloy, was evident in solutions of low chloride concentration; less striking differences were revealed in high chloride concentration. Both powder metallurgy and cast alloys show two main types of precipitates, which were identified as Zn-Mg and Zr-Sc base intermetallic phases. The microstructure of the PM alloys is refined compared with the cast material, which assists understanding of the corrosion performance. The corrosion process commences with dissolution of the Zn-Mg base phases, with the relatively coarse phases present in the cast alloy showing ready development of corrosion.     

Inhibitors performance in CO2 corrosion: EIS studies on the interaction between their molecular structure and steel microstructure

The performance of three imidazoline-like inhibitors in CO₂ corrosion was studied by means of electrochemical measurements employing a.c. and d.c. techniques. Carbon steel with two different microstructures (annealed, and quenched and tempered (Q&T)) was used in a deoxygenated 5% wt. NaCl solution, saturated with CO₂ at 40 °C and pH 6. Aminopropylimidazol (API) and two commercial imidazoline-based products (PC and QB) were used as inhibitors. Electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LRP) studies showed that the annealed samples have a better corrosion resistance than the Q&T samples when API and PC were added. On the other hand, the presence of QB yielded the opposite results. From the Bode phase angle plots it can be concluded that in the first case and for both microstructural conditions, there is no indication of formation of an inhibitor film, whereas in the presence of QB its formation is clearly evident. Based on these experimental findings, a mechanism of action for each inhibitor is proposed.