原子力显微镜研究苯并三氮唑对铜的缓蚀作用

铜以及铜合金由于其优良的抗腐蚀性能,广泛用在冷却水系统中,苯并三氮唑(BTA)常常作为铜的缓蚀剂。将传统电化学方法和原子力显微镜(AFM)测试技术相结合,对人造海水中BTA作用于铜电极的缓蚀行为进行了研究。结果表明,BTA能够有效减缓铜在海水中的腐蚀,且随着缓蚀剂浓度的增加,缓蚀效果越明显,100 mg/L的BTA就能够高效的保护铜。电化学结果表明,BTA能够在铜的表面形成致密的保护膜[CuBTA]n;AFM测试表明,随着时间的进行,保护膜越来越致密,保护性能也越好。     

1,2,3-苯并三氮唑铜缓蚀剂的研究进展

苯并三唑(BTAH)是一种非常有效的铜及其合金的缓蚀剂。到目前为止有许多关于BTAH缓蚀作用的研究,但其缓蚀机制仍然不为所知。对BTAH的缓蚀研究作出了总结,以便为进一步研究和开发新的高效缓蚀剂提供依据。     

有机中间体苯并三氮唑的合成工艺研究

研究了以邻硝基氯苯、水合肼、还原铁粉和盐酸为原料合成苯并三氮唑的工艺过程。筛选出最佳溶剂、反应温度和萃取剂。实验发现:溶剂正庚醇用量160ml/mol邻硝基氯苯,反应温度116℃,萃取剂为乙酸乙酯时,产品总收率为86.4%。     

铜及铜合金用缓蚀剂——苯并三氮唑及其衍生物的发展

苯并三氮唑是一种优秀的金属缓蚀剂，为提高其对多种金属及各种介质中的缓蚀 效率，进一步对其衍生物的开发研究工作已经受到科技界的关注。专家黄魁元简要介绍了国内外金属缓蚀剂“苯并三氮唑及其衍生物”对铜及铜合金在腐蚀性介质中及不同工艺条件下的缓触效果，并指出笨并三氮唑及其衍生物在金属防护中的开发研究前景。     

苯并三氮唑及其衍生物对铜的协同缓蚀效应

以苯并三氮唑(BTA)和溴代正丁烷为原料,采用一步法合成了N-丁基苯并三氮唑(N-BBTA),研究了BTA、N-BBTA以及N-BBTA与BTA的复配体系对铜在3％(质量分数)NaC1溶液中的缓蚀行为.结果表明,单一N-BBTA和BTA对铜均具有一定的缓蚀能力.当N-BBTA、BTA浓度为10 mmol/L时,缓蚀率分...     

膨润土对苯并三氮唑与Cu2+的吸附行为研究

以膨润土对含苯并三氮唑(BTA)和Cu2+的模拟废水进行吸附研究。结果表明:膨润土吸附BTA的最佳pH为3.5,对Cu2+的吸附率随pH升高而增大;pH为3.5时,对BTA、Cu2+的最大吸附率分别达到92.1%、40.3%;膨润土对100 mg/L BTA和Cu2+溶液的饱和吸附量分别为81.3、22.9 mg/g,吸附平衡时间为80～100 min。动力学拟合表明,吸附过程能用Freundlich和Langmuir吸附等温方程描述。     

1-羟甲基苯并三氮唑复配物的缓蚀性能研究

以苯并三氮唑(BTA)和甲醛为原料合成了l-羟甲基苯并三氮唑,将其与乙二胺复配得到一种新的铜缓蚀剂。通过静态挂片、极化曲线以及交流阻抗等实验方法对其缓蚀性能进行了测定。实验结果证明,该缓蚀剂在3%的10 mg/L NaCl溶液中对黄铜的缓蚀率达到90%,比BTA缓蚀效果有很大提高。极化曲线测试结果表明,1-羟甲基苯并三氮唑与乙二胺复配得到的是混合型缓蚀剂。     

固定化铜离子亲和膜静态吸附血红蛋白的性能研究

用固定化铜离子亲和膜静态吸附血红蛋白(Hb),考察了血红蛋白浓度、pH值、离子强度、温度和时间对吸附的影响.结果表明,固定化铜离子亲和膜静态吸附血红蛋白的最大吸附量为14.8719 mg·g-1,当控制温度16～25℃、pH值7.0 ～ 7.4、Hb浓度0.8484 ～ 1.2726 mg·mL-1时,吸附效果较好;离子强度越低,吸附效果越好;吸附时间至少为30 min.固定化铜离子亲和膜静态吸附血红蛋白的研究为实际体系的分离研究奠定了基础.     

苯并三氮唑和硅酸钠对铜的协同缓蚀作用

通过静态失重实验、电化学测试和扫描电镜等方法研究了苯并三氮唑(BTA)和硅酸钠单独和复配使用对铜在5%氯化钠溶液中的腐蚀抑制作用。结果表明:单独使用BTA,缓蚀效率随BTA浓度增加而提高;单独使用硅酸钠,质量浓度低于50mg/L会加速铜的腐蚀,高质量浓度硅酸钠则对铜在5%氯化钠溶液中的腐蚀具有缓蚀作用;BTA和硅酸钠组成复合缓蚀剂,在总质量浓度为20 mg/L条件下按不同比例复配,以16 mg/L BTA和4 mg/L硅酸钠复配使用能够降低腐蚀电流密度,产生协同缓蚀作用,属于混合抑制型缓蚀剂。     

An examination of surface waving on mercury film electrodes using scanning tunneling microscopy

Mercury film electrodes (mfe) have been prepared on several substrates and examined using scanning tunneling microscopy (STM). Surface waving was found to be at least one order of magnitude smaller in amplitude than that observed on bulk mercury drops. A solid/liquid/gaseous interface was observed, as was the amplitude of surface waves under various imaging conditions. No resonance condition was observed in these systems. A simple system for exciting surface waves was developed, and used to investigate surface waving of mercury during exposure to various conditions. The source of these waves remains unknown.     

Zirconium oxide supported on Pd(100): Characterization by scanning tunneling microscopy and tunneling spectroscopy

Scanning tunneling microscopy (STM) and tunneling spectroscopy (TS) were used to characterize the structure of a model metal-supported dispersed metal oxide, ZrO₂ on Pd(100). STM images illustrate changes in the surface morphology of the ZrO₂ resulting from various chemical treatments. When the sample was treated in O₂, the ZrO₂ appeared as a smooth, featureless overlayer of varying thickness wetting the Pd. After treatment in H₂, the ZrO₂ formed non-wetting particles on the Pd, with a sharp Pd-ZrO₂ interface. TS provided a fingerprint that verified the presence of a semiconducting overlayer on a metallic support. These results appear to be consistent with X-ray absorption spectra of ZrO₂ supported on Pd black, reported elsewhere.     

Direct observations of changes in surface structures by scanning tunneling microscopy

Recently, we have studied the interaction of reactive adsorbates H, C, O, and S with Ni and Cu surfaces by scanning tunneling microscopy (STM). In this paper, we briefly illustrate and discuss how such studies provide significant insight into the understanding of dynamic surface processes such as adsorbate-induced restructuring, surface reactions, and adsorbate-adsorbate interactions. The STM results demonstrate that there is a strong coupling between the chemisorption/reaction process and the distortion of the metal surface.     

Copper electrodeposition in sulphate solutions in the presence of benzotriazole

DC and pulse plating of copper in acidic sulphate solutions containing benzotriazole (BTA) has been studied. When BTA is the only additive present, it generally has a stronger effect than the plating mode and significantly enhances deposit morphology and surface brightness over that produced in additive-free solutions. XPS and voltammetry analyses indicate that BTA is present at the surface of the deposit, but not through the entire coating, and does not become depleted within the solution over the course of plating. This may help explain why the initial surface smoothness and brightness is maintained as the coating grows beyond 5 μm thick. Plating mode does have a strong effect on deposit morphology under specific conditions. Pulse current plating at low frequency (50 Hz) and low duty cycle (20%) produces deposits with poorer quality than that obtained by DC plating. Pulse reverse plating yields very coarse and dull coatings when the frequency is low enough for metal dissolution to occur during the reverse time. Regardless of the plating mode, the addition of Cl⁻ eliminates most of the beneficial effects of BTA and leads to very rough and dull deposits. The observed effects are discussed in light of previous research on the electrodeposition and corrosion of the Cu–BTA and Cu–BTA–Cl systems.     

The effect of benzotriazole on mass transfer in the corrosion of a copper rotating disk electrode

The effect of benzotriazole, BTA, on mass transfer in dissolution-corrosion of the copper rotating disk electrode in 0.02 M Fe(III)–0.5 M H₂SO₄ has been studied by means of atomic absorption spectrometry. The mass transfer coefficient, K, was determined from the slope of ln(C ₀/C)_Fe(III) vs. time plots. In the absence of BTA the corrosion process can be described by the correlation Sh = KR/D = 4.47Re ^0.5. The difference in values between Sh and Sh _Levich, and the change in slope in the Arrenhius plot points to mixed control for the cathodic process Fe³⁺ + 1e^– Fe ²⁺ and charge transfer control for the anodic process, Cu Cu²⁺ + 2e. The average activation energies were 7.7 kJ mol^–1 and 19.5 kJ mol^–1 at (500–1500) and (2000–3000) rpm, respectively. At low concentration of BTA the inhibiting action of BTA increases with concentration and with rotation speed. For [BTA] 5 × 10^–3 M, the K value, 10^–4 cm s^–1, remains constant and is independent of rotation rate. The morphology of the copper rotating disk after corrosion in the absence and presence of BTA was examined using scanning electron microscopy (SEM).     

脉冲铜沉积层织构及形貌的研究

采用脉冲电沉积工艺制备了铜沉积层,研究了电流密度、脉冲频率和占空比对铜镀层织构的影响。利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分析了铜镀层的织构和形貌。实验结果表明,低电流密度下为(200)晶面择优取向,高电流密度下为(111)晶面择优取向,频率越高则择优取向越强。低频脉冲下制备的沉积层平整致密。     

Use of laser scanning confocal microscopy for characterizing changes in film thickness and local surface morphology of UV-exposed polymer coatings

Laser scanning confocal microscopy (LSCM) has been used to characterize the changes in film thickness and local surface morphology of polymer coatings during the UV degradation process. With the noninvasive feature of LSCM, one can obtain thickness information directly and nondestructively at various exposure times without destroying the specimens or deriving the thickness values from IR measurement by assuming uniform film ablation. Two acrylic polymer coatings were chosen for the study, and the physical and chemical changes of the two systems at various exposure times were measured and analyzed. Those measurable physical changes caused by UV exposure include film ablation, formation of pits and other surface defects, and increases in surface roughness. It was found in both coatings that changes in measured film thickness by LSCM were not correlated linearly to the predicted thickness loss using the changes in the CH band obtained by the Fourier Transform Infrared (FTIR) spectroscopy measurements in the later degradation stages. This result suggested it was not a uniform film ablation process during the UV degradation. At later stages, where surface deformation became severe, surface roughness and profile information using LSCM were also proven to be useful for analyzing the surface degradation process Presented at the 81st Annual Meeting of the Federation of Societies for Coatings Technology, November 13–14, 2004 in Philadelphia, PA.