喹啉型双季铵盐酸化缓蚀剂的合成与性能评价

以喹啉和双卤代烃为原料经季铵化反应合成了三种喹啉型双季铵盐酸化缓蚀剂:溴化1,4-二喹啉丁烷(Q-4-Q)、溴化1,6-二喹啉己烷(Q-6-Q)和溴化1,8-二喹啉辛烷(Q-8-Q),采用核磁共振氢谱对其结构进行表征。采用失重法,电化学方法和SEM等方法研究了三种产物在15%HCl溶液中对N80钢的缓蚀性能。结果表明,Q-8-Q的缓蚀性能最佳;双季铵盐Q-8-Q与肉桂醛(CA)最佳复配比为cQ-8-Q∶cCA=1∶1。在15%HCl,90℃条件下,6mmol/L该复配缓蚀剂对N80钢片的缓蚀率达99.79%,缓蚀性能优良;缓蚀剂分子在N80钢片表面形成一层保护膜;该复配缓蚀剂能有效抑制酸液对N80钢表面的腐蚀,是一种以抑制阴极反应为主、属"负催化效应"作用机理的混合型缓蚀剂。     

乌洛托品季铵盐缓蚀剂的合成与复配研究

以乌洛托品、溴己烷为主要原料,甲醇为溶剂,合成了一种乌洛托品季铵盐缓蚀剂,采用失重法研究了季铵盐缓蚀剂在15%(质量分数) HCl溶液中的缓蚀性能及复配性能,并采用量子化学计算对缓蚀剂机理进行分析,通过红外光谱、SEM对腐蚀后表面进行分析。结果表明,季铵盐缓蚀剂具有良好的缓蚀性能,在15%HCl、90℃下,加量0.5%(质量分数)时,缓蚀率达98.41%,并且与聚乙二醇、KI、丙炔醇复配后协同增效效果较好;量子化学计算表明该季铵盐缓蚀剂分子活性主要分布在分子环上,与乌洛托品相比具有更小的能隙,在Fe表面也具有更大吸附能,因此乌洛托品季铵盐活性更高。表面分析实验进一步验证了该缓蚀剂分子在QT-800钢片表面形成一层吸附膜。     

高温高压H2S/CO2环境缓蚀剂分子结构与缓蚀性能关系的研究

用静态和动态腐蚀失重法研究喹啉季铵盐、吡啶季铵盐、曼尼希碱和咪唑啉季铵盐四种不同主体类型缓蚀剂在高温高压H₂S/CO₂环境中N80钢的缓蚀性能,并结合扫描电子显微镜（SEM）和X射线光电子能谱（XPS）表面分析技术研究了不同缓蚀剂主体分子结构与缓蚀性能的关系。结果表明,四类缓蚀剂的缓蚀效率的大小顺序是：喹啉季铵盐>吡啶季铵盐>曼尼希碱>咪唑啉季铵盐。喹啉季铵盐与其他三种缓蚀剂主体分子结构相比具有更好的抗硫性能,其对N80钢具有良好的吸附性能,可形成抗腐蚀性介质渗透能力强的致密均匀和稳定不易分解的有机膜。其缓蚀剂用量为0.15%时,缓蚀率可达97%。     

咪唑啉季铵盐缓蚀剂的复配机理

通过电化学测试确定咪唑啉季铵盐(IM)和辛基酚聚氧乙烯醚(OP)两种缓蚀剂的最佳复配比,利用X射线光电子能谱(XPS)分析高温高压CO_2腐蚀条件下缓蚀剂在L245钢表面的吸附特性,结合分子动力学计算研究了复配缓蚀剂的缓蚀机理。结果表明:复配后IM缓蚀剂分子在金属表面吸附量增加,同时OP分子的吸附提高了IM缓蚀剂分子在金属表面的吸附覆盖程度,形成致密的保护膜,阻碍溶液中腐蚀性介质对金属表面的侵蚀,有效保护基体减缓腐蚀,从而使得IM和OP复配后的缓蚀率明显升高;IM与OP复配后缓蚀剂分子在Fe(001)表面的吸附强度增大,说明缓蚀剂分子的缓蚀性能本质上是由缓蚀剂分子与金属表面的电子转移行为所决定的。     

含氮杂环双季铵盐在高温酸性溶液中的缓蚀性能

以喹啉为母体,对二氯苄为卤化剂合成一种含氮杂环双季铵盐,并对其结构进行红外表征;同时利用静态失重法、极化曲线、电化学阻抗谱(EIS)对其在高温酸性水介质中的缓蚀性能进行了研究.极化曲线表明该双季铵盐缓蚀剂为强烈的阴极型缓蚀剂,EIS表明含N 的杂环分子在低频区表现为明显的吸脱附感抗环,表明在弱阳极极化下季铵盐类缓蚀剂就会发生阳极脱附.失重试验和电化学测试表明其缓蚀性能良好,但进一步性能的提高还需要通过复配来降低其脱附敏感性.     

油松籽油酸洗缓蚀剂的合成与应用

以油松籽油、二乙烯三胺、氯化苄为原料,合成了咪唑啉季铵盐缓蚀剂Y-1,用失重法、极化曲线法评价了Y-1及其与硫脲复配后的新型缓蚀剂的缓蚀性能.结果表明:缓蚀剂Y-1在盐酸体系中对A20钢有很好的缓蚀效果,由Y-1和硫脲复配的新型缓蚀剂在柠檬酸体系中对A20钢的缓蚀效率在99.65％以上,并且二者都具有很好的热稳定性;缓...     

咪唑啉季铵盐缓蚀剂的合成及缓蚀行为的研究

本文以复合固体酸作催化剂,以油酸、二乙烯三胺、氯化苄为主要原料合成了咪唑啉季铵盐。用静态失重法、动电位极化曲线法、电化学阻抗法研究其在15%盐酸溶液中对A3钢的缓蚀性能。实验结果表明,缓蚀剂的缓蚀效率随着缓蚀剂浓度的增加而增加但随着温度的升高而减小。缓蚀剂浓度为10g/L时,用静态失重法测其在60℃15%盐酸溶液中的缓蚀效率为99.18%,当缓蚀剂与KI复配时,两者产生良好的协同效应:缓蚀剂与KI质量比为5:1的时候,缓蚀效率为99.7%。该缓蚀剂在A3钢表面的吸附遵循Langmuir吸附等温模型。动电位极化曲线测试表明该缓蚀剂是以抑制阴极为主的混合型缓蚀剂。     

酸化缓蚀剂含羟基双季铵盐的合成及性能评价

根据季铵化反应原理,以喹啉和1,3-二氯-2-丙醇合成了一种含羟基双季铵盐酸化缓蚀剂(BQ-1)。用红外光谱对其结构进行了表征,采用静态失重法和电化学测试研究了该缓蚀剂在15%HCl溶液中对N80钢的缓蚀性能。结果表明,该缓蚀剂具有明显的腐蚀抑制能力,在15%HCl、90℃下,5mmol/L该缓蚀剂对N80钢片的缓蚀率达96%以上,缓蚀性能优良;此外,该缓蚀剂是一种混合型缓蚀剂,在N80钢片表面的吸附作用符合Langmuir等温吸附规律。表面分析试验(SEM和EDS)验证了缓蚀剂分子在N80钢片表面确实形成了一层保护膜。     

盐酸介质中锌缓蚀剂的研制

采用正交试验方法对喹啉、吖啶、季铵盐类化合物进行复配得到一种盐酸介质中锌的优良缓蚀剂.利用失重法、电化学极化曲线法、扫描电镜对其缓蚀性能进行了评价.结果表明该复合缓蚀剂缓蚀率高,是一种阴极型缓蚀剂,扫描电镜照片显示无点蚀、晶间腐蚀等非均匀腐蚀现象.     

一种复合型咪唑啉缓蚀剂

以油酸和二乙烯三胺为原料合成咪唑啉季铵盐缓蚀剂后,在50℃、5%的盐酸溶液中用静态失重法对咪唑啉季铵盐与阴离子表面活性剂和无机阴离子进行研究,得到了一个与咪唑啉季铵盐有最佳复配效果的复配体,咪唑啉季铵盐与I-复配比为1∶1(质量比)时,缓蚀剂的缓蚀效果最佳。在不同时间和不同温度下对复合型缓蚀剂的缓蚀效率进行了测量。这种缓蚀剂对A3钢的缓蚀率达到99%以上,比单独用咪唑啉季铵盐缓蚀效率提高了0.7%。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.     

电化学噪声数据处理方法概述

综述了常见的电化学噪声数据处理方法,介绍了直流趋势剔除、统计分析、快速傅立叶变换(FFT)法计算功率谱密度(PSD)以及小波变换处理电化学噪声信号的基本过程,并阐释了各种数学处理及所得参数的物理意义。