Nehal S. Ahmed

Nehal S. Ahmed


Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 1999 in Fuel
Verified
Journal Article
Closed access
NANehal S. Ahmed
Nehal S. Ahmed
ANAmal M. Nassar
Amal M. Nassar
NZNael N. Zaki
Nael N. Zaki
HGHussein Kh. Gharieb
Hussein Kh. Gharieb

1 June 1999 in Petroleum Science and Technology
Verified
Journal Article
Closed access
NANehal S. Ahmed
Nehal S. Ahmed
ANAmal M. Nassar
Amal M. Nassar
NZNael N. Zaki
Nael N. Zaki
HGHussein Kh. Gharieb
Hussein Kh. Gharieb
The stability and rheology of an Egyptian Heavy crude oil-in-water emulsions stabilized by an anionic (TDS) and a nonionic (NPE) surfactants individually or in a mixture have been studied. The study reveals that, the viscosity of the crude oil decreases when it is emulsified with water in the form of an oil-in-water type of emulsion. The stability of the oil-in-water emulsion increases as the surfactant concentration and speed of mixing of the emulsion increases. Fresh water and synthetic formation water have been used to study the effect of aqueous phase salinity on the stability and viscosity of the emulsion. Surfactant dissolved in synthetic formation water has been utilized to find out the possibility of injecting the surfactant into a well bore to effect emulsification in the pump or tubing for enhancing the production of heavy crude oils as oil-in-water emulsion. The study revealed that, the viscosity of the emulsion containing fresh water is always less than that containing formation water, these findings have been correlated with the crude oil/water interracial tension (IFT) measurements The decreased IFT value results in a decrease in the average particle size of the dispersed crude oil leading

1 December 2012 in Journal of Petroleum Science and Engineering
Verified
Journal Article
Closed access
SMSalah A. Mohamad
Salah A. Mohamad
NANehal S. Ahmed
Nehal S. Ahmed
SHSaeed M. Hassanein
Saeed M. Hassanein
ARAhmed M. Rashad
Ahmed M. Rashad

1 May 2005 in Petroleum Science and Technology
Verified
Journal Article
Closed access
ANAmal M. Nassar
Amal M. Nassar
NANehal S. Ahmed
Nehal S. Ahmed
RSRasha S.Kamal
Rasha S.Kamal
AAAbdel-Azim A. Abdel Azim
Abdel-Azim A. Abdel Azim
EEE. I. El-Nagdy
E. I. El-Nagdy

8 January 2009 in Petroleum Science and Technology
Verified
Journal Article
Closed access
AAA. A. A. Abdel Azim
A. A. A. Abdel Azim
ANA. M. Nasser
A. M. Nasser
NANehal S. Ahmed
Nehal S. Ahmed
AKA. F. El Kafrawy
A. F. El Kafrawy
RSRasha S.Kamal
Rasha S.Kamal
In the present work, some polymeric additives based on styrene-maleic anhydride copolymer were prepared and evaluated as multifunction lube oil additives (viscosity index improvers, pour point depressants, and detergent-dispersant additives). The styrene-maleic anhydride copolymer reacted with different alcohols (dodecyl alcohol, hexadecyl alcohol, octadecyl alcohol, and docosanol) to prepare four different types of esters and aminated with different types of amines (dodecyl amine, hexadecyl amine, and octadecyl amine) to prepare another three co-polymeric additives. Structure of the prepared compounds was confirmed by I.R. spectroscopy. The molecular weights of the prepared copolymers were determined by using gel permeation chromatograph and the percentage of esterification and amination were determined by 1HNMR. The efficiencies of the prepared compounds as viscosity index improvers, pour point depressants, and detergents-dispersants were investigated. It was found that the efficiency of the prepared compound as viscosity index improvers increases with increasing the concentration of additives in the solution and with increasing the molecular weight of prepared compounds, while the efficiency of the prepared compounds as pour point depressants increases with decreasing the concentration of the prepared polymers. On the other hand, the prepared compounds showed excellent dispersion power.

1 January 2016 in Tribology International
Verified
Journal Article
Closed access
ANAmal M. Nassar
Amal M. Nassar
NANehal S. Ahmed
Nehal S. Ahmed
HAHamdy S. Abdel-Hameed
Hamdy S. Abdel-Hameed
AEAhmed F. El-Kafrawy
Ahmed F. El-Kafrawy