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1.
猪殃殃草提取物在盐酸中对Q235钢的缓蚀作用研究   总被引:1,自引:1,他引:0  
目的开发盐酸清洗领域的天然绿色缓蚀剂。方法通过95%乙醇浸提法从猪殃殃草茎叶中提取植物缓蚀剂,用红外光谱(FTIR)表征了其主要官能团,采用失重法、极化曲线和电化学阻抗(EIS)谱研究了其在1 mol/L盐酸介质中对Q235钢的缓蚀性能,并探讨了缓蚀机理。结果猪殃殃草提取物可明显减缓Q235钢在1 mol/L盐酸介质中的腐蚀,属阴极控制为主的混合型缓蚀剂,缓蚀效率随其浓度的增加而增大,当其质量浓度达到1.2 g/L时,25℃下的缓蚀效率可达82%以上,受浸泡时间的影响不大。其缓蚀机理为"几何覆盖效应",有效缓蚀成分在Q235钢表面的吸附符合Langmuir等温式,吸附平衡常数为10.62 L/g,且属于物理吸附。结论在1 mol/L盐酸溶液介质中,猪殃殃草提取物对Q235钢的缓蚀作用明显,是一种在盐酸清洗领域有一定应用价值的环境友好型缓蚀剂。  相似文献   

2.
目的研究在0.5 mol/L硫酸溶液介质中,桂花果提取液(OFFE)对Q235钢的缓蚀作用及机理。方法通过失重法和极化曲线、电化学阻抗谱等电化学方法研究了桂花果提取液对Q235钢在0.5 mol/L硫酸溶液介质中的缓蚀性能,考察了25℃下桂花果提取液浓度对缓蚀效率的影响,并对缓蚀机理进行了探讨。结果以95%的乙醇为溶剂浸提制备的桂花果提取液在0.5 mol/L硫酸介质中对Q235钢具有良好的缓蚀性能,缓蚀效率随其质量浓度的增加而增大,当其浓度达到10 g/L时,其缓蚀效率可达91.48%。电化学测试结果表明,桂花果提取液为混合型缓蚀剂,主要通过抑制阴极析氢过程来减缓Q235钢的腐蚀,缓蚀机理为"几何覆盖效应",其有效缓蚀成分在Q235钢表面的吸附符合Langmuir等温式,吸附平衡常数为1.09 L/g。结论在0.5 mol/L的硫酸介质中,桂花果提取液对Q235钢具有明显的缓蚀作用,是一种有广泛应用前景的天然绿色缓蚀剂。  相似文献   

3.
目的研究苯胺四聚体PEG两亲性嵌段共聚物(PEG-TA)对Q235钢在1 mol/L HCl介质中的缓蚀性能。方法采用静态失重测试、电化学测试、腐蚀表面形貌分析研究了自制的PEG-TA在1 mol/L HCl介质中对Q235钢的缓蚀性能,并探讨了其在Q235钢表面的吸附行为。结果红外和紫外表征表明,氨基封端苯胺四聚体和聚乙二醇为原料成功合成了两亲性嵌段共聚物PEG-TA。极化曲线研究表明,PEG-TA的加入明显可以抑制Q235钢在1 mol/L HCl介质中的腐蚀,且随着PEG-TA浓度的增加,缓蚀效果越好,在25℃的实验温度范围内,质量浓度为30 mg/L时,PEG-TA的缓蚀效率可以达到93.97%,属于阴极抑制为主的混合型缓蚀剂。电化学阻抗图谱研究表明,随着PEG-TA浓度的增加,Q235钢表面腐蚀反应的电荷转移电阻和膜电阻逐渐增大,钢表面缓蚀剂的含量和覆盖率增加,腐蚀抑制性增强。PEG-TA缓蚀剂分子在Q235钢表面的吸附遵循Langmuir等温模型,并且属于物理和化学混合吸附。SEM研究证明,在1 mol/L HCl中,PEG-TA可有效地抑制碳钢的腐蚀。结论 PEG-TA在1 mol/L HCl中有效提高了Q235钢的耐蚀性,是一种高效环保的缓蚀剂。  相似文献   

4.
利用极化曲线、电化学阻抗谱研究了节节草提取物对Q235钢在盐酸溶液中的缓蚀性能。结果表明,采用热水浸提法得到的节节草提取物,可明显减缓Q235钢在1 mol·L-1HCl溶液中的腐蚀,属阴极抑制为主的混合型缓蚀剂。提取物的缓蚀性能随浓度增大而增强,并在实验温度范围内较稳定。阻抗数据拟合结果表明,提取物中的缓蚀剂分子在Q235钢表面的吸附同时符合Langmuir和Dhar-Flory-Huggins等温吸附方程。光谱分析和SEM观察分别证实了提取物在Q235钢表面的吸附及其对Q235钢在盐酸中的缓蚀作用。  相似文献   

5.
目的研究4-苯基氨基硫脲(4-PTC)对Q235钢在1mol/L HCl中的缓蚀作用。方法采用异硫氰酸苯酯和水合肼为原料,合成4-PTC。采用熔点分析、核磁共振氢谱和红外光谱等方法确定合成物质为目标产物4-苯基氨基硫脲。采用静态失重法、电化学极化曲线法、电化学阻抗谱法和扫描电子显微镜法,分析研究4-PTC的缓蚀性能。结果静态失重实验表明,当4-PTC浓度增加到1.0 mmol/L时,缓蚀效率达到85.9%,在Q235钢表面吸附符合Langmuir吸附等温式,形成单分子吸附层。计算得到吉布斯自由能为?35.60 k J/mol,说明缓蚀剂分子在Q235钢表面吸附同时存在物理吸附和化学吸附过程。动电位极化曲线表明,该缓蚀剂是以阴极型为主的混合型缓蚀剂,当4-PTC浓度增加到1.0 mmol/L时,缓蚀效率达到83.6%。电化学阻抗谱表明,随4-PTC浓度的增加,电荷转移电阻值增大,双电层电容值减小,金属腐蚀速率降低,缓蚀作用增强。当4-PTC浓度增加到1.0 mmol/L时,缓蚀效率达到84.7%。扫描电子显微镜表明,缓蚀剂分子能有效保护金属表面,抑制腐蚀。结论在盐酸介质中,4-PTC对Q235钢具有优良的缓蚀性能。  相似文献   

6.
咪唑啉季铵盐对Q235钢在盐酸溶液中的缓蚀性能   总被引:3,自引:0,他引:3  
合成了苯乙酸咪唑啉季铵盐(PAIPI)和萘乙酸咪唑啉季铵盐(NAIPI),通过失重法、电化学方法研究了两者在1 mol/L HCl中对Q235钢的缓蚀性能,并探讨了其在Q235钢表面的吸附行为.结果表明,两者在1 mol/LHCl中对Q235钢均为阳极型缓蚀剂,其中NAIPI对Q235钢的缓蚀性能优于PAIPI;两者在Q235钢表面均是单层吸附,属于物理吸附.  相似文献   

7.
刘倩  刘金彦  王佳  种瑶 《表面技术》2022,51(10):250-259, 208
目的 探究2-巯基苯并咪唑(MBI)、L-半胱氨酸(L-cysteine)以及两者的混合体系在1 mol/L HCl溶液中对Q235钢的缓蚀性能。方法 通过静态失重法、电化学阻抗谱以及极化曲线研究MBI与L-cysteine的最佳复配条件,并借助原子力显微镜(AFM)以及X射线光电子能谱仪(XPS)分析探究MBI、L-cysteine单独以及复配后在碳钢表面的作用机理。结果 当在HCl溶液中加入5×10?3 mol/L的MBI时,缓蚀效率达到88.01%,而相同浓度下,L-cysteine的缓蚀效率仅达60.19%,缓蚀作用有限。当MBI和L-cysteine复配时,二者的混合体系在HCl介质中具有很好的缓蚀效果,特别是当浓度为1×10?3 mol/L、复配比为9∶1时,缓蚀效果达到最佳,协同效应也最明显。电化学法所得结果和失重法保持一致,且进一步表明MBI和L-cysteine的混合体系同时抑制腐蚀反应的阴、阳极过程,其中抑制阴极的效果最显著。AFM形貌图以及XPS谱图分别表明浸泡在含有MBI-L-cysteine(浓度为1×10?3 mol/L,复配比为9∶1)溶液中的Q235钢表面更加平整,MBI-L-cysteine在Q235钢上通过吸附形成的保护膜可以显著增强Q235钢的耐酸性。结论 MBI与L-cysteine(浓度为1×10?3 mol/L,复配比为9∶1)在1 mol/L HCl溶液中对Q235钢有显著的协同缓蚀性能,但协同效应会随着L-cysteine的增多而逐渐消失。  相似文献   

8.
合成了一种吡啶席夫碱衍生物,2-吡啶甲醛缩4-苯基氨基硫脲席夫碱(PCPTC),并采用失重法、电化学阻抗谱法和极化曲线法研究了PCPTC对Q235钢在1 mol/L HCl溶液的缓蚀作用。结果表明:PCPTC对Q235钢在1mol/L HCl溶液中具有优良的缓蚀效果,是一种混合型缓蚀剂;当缓蚀剂浓度达到0.5 mmol/L时,缓蚀率达到93.6%;PCPTC在Q235钢表面的吸附符合Langmuir吸附等温式;扫描电镜(SEM)观察表明,PCPTC可以有效保护Q235钢。  相似文献   

9.
新型三唑衍生物缓蚀剂在HCl中的缓蚀性能   总被引:1,自引:0,他引:1  
用失重法、电化学方法研究新型三唑衍生物在1 mol/L HCl中缓蚀性能以及在Q235-A钢表面的吸附行为.结果表明,新型三唑缓蚀剂是一种混合型缓蚀剂,在1 mol/L HCl溶液中最高缓蚀率达到95%以上,在Q235-A钢表面的吸附行为符合Langmuir吸附等温式,且吸附为吸热反应.  相似文献   

10.
向云刚  崔益顺  谯康全 《表面技术》2015,44(10):105-110
目的研究十六烷基二甲基乙基溴化铵(CDAB)与NH4SCN在硫酸介质中对Q235钢的缓蚀协同效应,并探讨其缓蚀机理和性能,以期为工业实际生产提供理论数据。方法运用失重法研究CDAB质量浓度与缓蚀率的关系,通过失重法、动电位极化曲线法和交流阻抗法分析CDAB与NH4SCN复配后的缓蚀率和缓蚀机理。结果仅添加CDAB时,缓蚀率随着CDAB质量浓度增大而增大,但缓蚀性能并不显著,当质量浓度为10 mg/L时缓蚀率仅为85.07%;当CDAB与30 mg/L的NH4SCN复配后,缓蚀率显著提高到96.73%,能有效抑制Q235钢在0.5 mol/L硫酸介质中的腐蚀。极化试验结果显示,该复配缓蚀剂是一种以控制阳极反应为主的混合型缓蚀剂,缓蚀率随CDAB质量浓度增大而增大,与交流阻抗法、失重法试验结果相一致。复配缓蚀剂在Q235钢表面的吸附服从Langmiur吸附等温模型,吸附吉布斯自由能ΔG0=-48.33 k J/mol,为自发吸附。结论 CDAB与NH4SCN在0.5 mol/L硫酸介质中具有优异缓蚀协同效应,能有效抑制腐蚀介质对Q235钢在的腐蚀,复配缓蚀剂具有较高的缓蚀率。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

16.
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).  相似文献   

17.
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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