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Macroscopic Studies on the Properties of the Anodic Oxide Films on Titanium

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Journal of Materials Science & Technology 1998年第3期14卷 241-246页

作者： Mahdy, G.A. Mahmoud, S.S. chemistry dept. Faculty of Science Helwan University Helwan Cairo Egypt chemistry dept. University College for Women Ain-Shams University Helopolis Cairo Egypt

The effect of fluoride ions on the formation and dissolution behaviour of anodic oxide films on Ti has been investigated in acidic fluoride media (pH=1) using impedance and galvanostatic techniques. A5 the fluoride ion concentration and temperature increase the rate of oxide film formation decreases while the dissolution process increases. oxide film formed at high tem-perature and formation voltage was found to contain more defect sites in the film than that formed at a lower one. Activation energies are calculated during the oxide film formation and dissolution and found to be 20.76 and 28.72 kJ/mol, respectively. Formation rate and reciprocal capacitance data are reported as a function of polarizing current density. Values are recorded for the electrolytic parameters A and B. Potentiostatic curves are derived from the galvanostatic results.

关键词： Figure Macroscopic Studies on the Properties of the Anodic Oxide Films on Titanium

A novel green inhibitor for C-steel corrosion in 2.0 mol·L^-1 hydrochloric acid solution

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中国化学工程学报：英文版 2017年第3期25卷 373-380页

作者： A.Y.El-Etre A.I.Ali chemistry dept. Faculty of ScienceBertha UniversityBerthaEgypt

The corrosion inhibition characteristics of aqueous extract of seeds of Melia azedarach L.(MA) have been studied as eco-friendly green inhibitor for corrosion control of C-steel in 2 mol·L^(-1) HCl solution by gravimetric and electrochemical methods. The results depict that, the extract inhibits efficiently the corrosion of carbon steel in hydrochloric acid. The efficiency of extract is increased with increasing the extract concentration but independent on the studied temperature. The adsorption of the extract components onto the steel surface was found to be spontaneous, and follows Langmuir adsorption isotherm. The surface morphology of C-steel, in the absence and presence of MA extract in 2.0 mol·L^(-1) hydrochloric acid solution, was studied using scanning electron microscopy(SEM).

关键词： Corrosion inhibition C-steel Melia azedarach L.extract

Indole and Its Derivatives as Corrosion Inhibitors for C-Steel during Pickling

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Journal of Materials Science & Technology 2000年第3期16卷 291-296页

作者： S.H.Sanad, A.A.Ismail and A.A.El-Meligi (Physical chemistry dept., National Research Centre, Dokki, Cairo, Egypt) Physical chemistry dept. National Research Centre Dokki Cairo Egypt

The corrosion of three types of C-steel in 10% hydrochloric acid solution has been investigated in the absence and the presence of the inhibitors, indole (A), indole acetic acid (B), indole butyric acid (C), and 3-acetyl indole (D), by weight-loss measurements at different temperatures (30～70℃). The results showed that inhibiting efficiency depended upon the presence of the substituted groups in the pyrrole ring. The inhibiting efficiency of the inhibitors increased in the order: Inh. C

关键词： Carbon steel

Efficiency of Chalcone Compounds Inhibitors for Acid Corrosion of Al and Al-3.5Mg Alloy

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Journal of Materials Science & Technology 1996年第4期12卷 267-272页

作者： I. Z. Selim A. A. Khedr and K.M.EI-Sobki(Physical chemistry dept., National Research Centre, Dokki, Cairo, Egypt) Physical chemistry dept. National Research Centre Dokki Cairo Egypt

Corrosion inhibition of Al and Al-3.5Mg alloy by organic compounds, namely chalcones in hydrochloric acid solutions has been investigated by rapid polarization technique and weight loss method. Polarization measurements show that, the inhibitors act cathodically both in case of Al and Al-3.5Mg alloy. It was found from the weight loss measurements that, the inhibition efficiency depends on the substituent in the chalcone compound. The relative inhibitive efficiency of these compounds has been explained on the basis of structure dependent electron donor properties of the inhibitors and the metal inhibitor interaction on the surface. The inhibition efficiency ranges from 16 to 64% for Al and from 30% to 91% for Al-3.5Mg alloy

关键词： Al Efficiency of Chalcone Compounds Inhibitors for Acid Corrosion of Al and Al-3.5Mg Alloy

Inhibitive Effect of Some Aldehydes on Corrosion ofAl-3Mg Alloy in Acid Solutions

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Journal of Materials Science & Technology 1998年第4期14卷 313-319页

作者： I.Z.Selim (Physical chemistry dept., National Research Center, Dokki, Cairo, Egypt) Physical chemistry dept. National Research Center Dokki Cairo Egypt

2M hydrochloric acid solution was used and the methods of polarization and weight loss measurements were adopted. The two methods give the same order of inhibition efficiency. Polarization studies reveal that catholic polarization is more pronounced than the anodic one. The results indicate that all the studied compounds excellent corrosion inhibitors and the percentage efficiency varying with both the type and concentration of the inhibitor and being in the following order: p-methoxy-benzaldehyde (1)benzaldehyde (2)p-chlorobenzaldehyde (3)p-nitrobenzaldehyde (4). The degree of surface coverage of the adsorbed additives was determined and the results obey the Langmuir isotherm. Effect of temperature on the corrosion rate in absence and presence of different concentrations of the used inhibitors was investigated by using weight loss measurements. The results indicate that the corrosion rate rapidly increases with increasing temperature. (Edited author abstract) 19 Refs.

关键词： Champion benzaldehyde blank Adsorption Singh Pearson Chapman Egypt London

Corrosion Penetration and Crystal Structure of AA5022 in HCl Solution and Rare Earth Elements

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Journal of Materials Science & Technology 2005年第3期21卷 324-330页

作者： A.A.El-Meligi S.H.Sanad A.A.Ismail A.M.Barakat Electrochem. and Corrosion Lab. Physical Chemistry Dept. National Research Centre Dokki Cairo EgypElectrochem. and Corrosion Lab. Physical Chemistry Dept. National Research Centre Dokki Cairo EgypElectrochem. and Corrosion Lab. Physical Chemistry Dept. National Research Centre Dokki Cairo EgypChemistry Dept. Faculty of Science Cairo University Cairo Egypt

Al-alloy (AA5022) corrosion penetration (CP) and crystal structure were investigated after running static immersion corrosion tests in 1 mol/L HCl solution and different concentrations of rare earth elements (La3+), (Ce3+) and their combination, at different temperatures. X-ray diffraction (XRD) was used to examine the surface structure before and after immersion, and secondary electron detector (SED) was operated to study surface morphology. In 1 mol/L HCI solution the corrosion penetration increased with increasing temperature and immersion time. The increase of La3+ concentrations up to 1000×10-6 g/L led to the decrease in the corrosion penetration, and the decrease in Ce3+ concentrations up to 50×10-6 g/L decreases the corrosion penetration of the alloy. Mix3 (combination of La3+ and Ce3+) dramatically reduced the corrosion penetration. This suggests that a synergistic effect exists between La3+ and Ce3+. The reaction kinetics both in absence and presence of La3+ and Ce3+ and their combination would follow a parabolic rate law. The XRD patterns revealed that the intensities of certain hkl phases are affected. The crystalline structure has not been deformed either before or after testing and there are no additional peaks except that of the as-received alloy. In the case of accelerating CP, the surface morphology shows that the roughness and voids of surface are increased.

关键词： Al-alloy Corrosion penetration Crystal structure XRD

Electron Spin Resonance of FeCl_3-filled Polyvinylidene Fluoride

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Journal of Materials Science & Technology 1997年第3期13卷 194-198页

作者： A.Tawansi H.I.Abdel-Kader and E.M.Abdel-Razek(dept. of Physics, Faculty of Science, Mansoura University, 35516, Egypt)M I Ayad(dept. of chemistry Almonofeya University, Shebeen E1-Koam, Egypt) dept. of Physics Faculty of Science Mansoura University Egypt dept. of chemistry Almonofeya University Shebeen El-Koam Egypt

Electron spin resonance (ESR) measurements were carried out at room temperature (=294 K),for FeCl3-filled polyvinylidene fluoride (PVDF) films, over the filling mass fraction range of 0 详细信息

Electron spin resonance (ESR) measurements were carried out at room temperature (=294 K),for FeCl3-filled polyvinylidene fluoride (PVDF) films, over the filling mass fraction range of 0

关键词： Figure Spin

Inhibiting Effect of Indole and Some of Its Derivatives on Corrosion of C-Steel in HCl

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Journal of Materials Science & Technology 2000年第4期16卷 397-400页

作者： A.A.Ismail, S.H.Sanad and A.A.El-Meligi (Physical chemistry dept., National Research Centre, Dokki, Cairo, Egypt) Physical chemistry dept. National Research Centre Dokki Cairo Egypt

The Inhibiting effect of indole (A), indole acetic acid (B), indole buteric acid (C), and 3-acetyl indole (D). on the corrosion of three carbon steels in 10% HCl was investigated by using galvanostatic polarization method and open circuit potential measurements. It was observed that the inhibiting action of inhibitors increased with increasing inhibitor concentration. The best inhibiting effect obtained at the highest concentration (200×10^(-6)g/L) of the inhibitors for the three carbon steels. According to polarization and open circuit potential methods the inhibitors have effect on both anodic and cathodic area.

关键词： Nitrogen compounds

Effect of inorganic additives on physical and chemical properties of PEO-LiClO_4 polymer electrolyte for lithium-ion batteries

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Journal of Harbin Institute of Technology(New Series) 2009年第6期16卷 869-872页

作者：顾大明李已才杨柳王淑堂 dept. of chemistry Harbin Institute of Technology

Inorganic additives-added PEO-based solid composite polymer electrolyte (SCPE) was prepared using solution casting method. The effects of LiNi0.8Co0.2O2 on the physical and chemical properties of the electrolyte were investigated. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR) and differential scanning calorimetry (DSC). The electrochemical performances of SCPE were measured. Results show that properties of the SCPE are improved significantly by adding LiNi0.8Co0.2O2 into PEO polymer electrolyte. Its conductivity reaches 5×10-4 S/cm(25 ℃) while retaining good mechanical and processing properties.

关键词： solid composite polymer electrolyte electrochemical properties PEO LiC1Q LiNio. ~ Coo.2 02