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ON SOME GEOMETRIC PROPERTIES OF QUADRIC SURFACES IN EUCLIDEAN SPACE
( Ahmad T. Ali ),( H. S. Abdel Aziz ),( Adel H. Sorour ) 호남수학회 2016 호남수학학술지 Vol.38 No.3
This paper is concerned with the classifications of quadric surfaces of first and second kinds in Euclidean 3-space satisfying the Jacobi condition with respect to their curvatures, the Gaussian curvature K, the mean curvature H, second mean curvature H< sub >II< /sub > and second Gaussian curvature K< sub >II< /sub >. Also, we study the zero and non-zero constant curvatures of these surfaces. Furthermore, we investigated the (A, B)-Weingarten, (A, B)-linear Weingarten as well as some special (C2, K) and (C2, K □)-nonlinear Weingarten quadric surfaces in E< sup >3< /sup >, where A ≠ B, A, B ∈ {K, H, H< sub >II< /sub >, K< sub >II< /sub >} and C ∈ {H, H< sub >II< /sub >, K< sub >II< /sub >}. Finally, some important new lemmas are presented.
ON SOME GEOMETRIC PROPERTIES OF QUADRIC SURFACES IN EUCLIDEAN SPACE
Ali, Ahmad T.,Aziz, H.S. Abdel,Sorour, Adel H. The Honam Mathematical Society 2016 호남수학학술지 Vol.38 No.3
This paper is concerned with the classifications of quadric surfaces of first and second kinds in Euclidean 3-space satisfying the Jacobi condition with respect to their curvatures, the Gaussian curvature K, the mean curvature H, second mean curvature $H_{II}$ and second Gaussian curvature $K_{II}$. Also, we study the zero and non-zero constant curvatures of these surfaces. Furthermore, we investigated the (A, B)-Weingarten, (A, B)-linear Weingarten as well as some special ($C^2$, K) and $(C^2,\;K{\sqrt{K}})$-nonlinear Weingarten quadric surfaces in $E^3$, where $A{\neq}B$, A, $B{\in}{K,H,H_{II},K_{II}}$ and $C{\in}{H,H_{II},K_{II}}$. Finally, some important new lemmas are presented.
A. Madhan Kumar,S. Fida Hassan,Ahmad A. Sorour,M. Paramsothy,M. Gupta 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.1
Magnesium (Mg) based implant materials are believed to be the perfect candidates for biomedical applications due to theirversatile properties. However, regulating their corrosion/degradation rate in the biological surroundings is still a noteworthytask. Suitable strategies to overcome this task is to wisely select alloy elements with improved corrosion resistanceand mechanical characteristics. An attempt has been made to enhance the corrosion and biocompatibility performance ofmagnesium alloy AZ31 containing carbon nanotubes (CNTs) as reinforcement and evaluate its degradation and invitromineralization performance in physiological medium. Corrosion behavior of AZ31 alloy with CNTs reinforcement wasinvestigated using electrochemical methods, weight loss, and hydrogen evolution in SBF during short and long-term periods. The obtained results revealed that the corrosion resistance of AZ31 alloy enhanced significantly due to the incorporationof CNTs. Hydrogen evolution test and weight loss tests revealed that the presence of CNTs improves the stability of theMg(OH)2 and efficiently regulate the degradation behavior in SBF. Surface characterization after immersion in SBF revealedthe rapid formation of bone-like apatite layer on the surface, validated a good bioactivity of the AZ31 nanocomposite samples.
Akeem Yusuf Adesina,Muzafar Hussain,Abbas Saeed Hakeem,Abdul Samad Mohammed,Muhammad Ali Ehsan,Ahmad Sorour 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9
This study investigates the influence of heating rate on the tribological and corrosion properties of 52100 bearing steelsamples consolidated via spark plasma sintering. The consolidation was conducted at different heating rates of 50, 100,200, 300, and 400 °C/min and the thermomechanical properties of the resulting samples were characterized. Ball-on-disctribological tests and electrochemical techniques were used to evaluate the wear and corrosion resistance, respectively. The results showed that an increased heating rate positively affects the thermomechanical and tribological properties of52100 bearing steel. The sintered samples exhibited a low coefficient of friction (between 0.4 and 0.56) and a low wear rate(between 1.4 and 1.8 × 10−6 mm3/Nm) at heating rates between 100 and 400 °C/min. Furthermore, the corrosion resistanceof the samples gradually drops above the heating rate of 100 °C/min. The samples can be ranked in the order of decreasingcorrosion resistance thus: 100 > 200 > 300 > 400 > 50 °C/min. The improved corrosion resistance of the sample sintered at100 °C/min can be attributed to its refined crystal size and high density.
Progress in the development of sour corrosion inhibitors: Past, present, and future perspectives
Bio-Composites,Moses M. Solomon,Saviour A. Umoren,Rami Suleiman,Mohamed Elanany,Nayef M. Alanazi,Ahmad A. Sorour 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.79 No.-
Metallic pipelines and gathering tanks play a vital role during oil and gas exploration, production,transmission, and processing. These facilities are usually attacked by corrosion. The use of corrosioninhibitors is one of the most economical and reliable approaches to control the corrosion of oil and gasmetallic facilities. This paper looks at the progress made in the development of sour corrosion inhibitorsfrom early 1900 to date. Scientific literatures were reviewed. The review identified four classes of organiccorrosion inhibitors for sour environments, namely, amine-based, imidazoline-based, polymer-based,and Gemini-surfactant-based inhibitors. The strengths and weaknesses of these inhibitors werehighlighted. The review revealed that the patronage of amine-based chemistries has declined, and thecurrent technology is based on imidazoline and quaternary salt chemistries. The existing knowledge gapand the future research direction in the area of sour corrosion inhibitors development have beenhighlighted.