Mohamed Hamza - Academia.edu (original) (raw)

Papers by Mohamed Hamza

Research paper thumbnail of Efficacy of Dexmedetomidine Versus Morphine as an Adjunct to Bupivacaine in Caudal Anesthesia for Pediatric Thoracic Surgeries: A Randomized Controlled Trial

Anesthesiology and Pain Medicine, 2021

Background: Caudal anesthesia is an effective method of pain management, which can be successfull... more Background: Caudal anesthesia is an effective method of pain management, which can be successfully employed to minimize post-thoracotomy pain in pediatric patients. However, its main disadvantage is the short postoperative analgesic period, which can be prolonged by the concurrent administration of one of many adjuvants. Objectives: This prospective randomized, blinded study aimed to compare the efficacy of dexmedetomidine versus morphine as adjuvants to bupivacaine in caudal anesthesia for thoracic surgeries in pediatric patients. Methods: Fifty patients were randomly allocated into two equal groups. To achieve caudal epidural block anesthesia, the patients in group M (n = 25) were administered morphine and bupivacaine, while group D (n = 25) received a mixture of dexmedetomidine and bupivacaine. The primary outcome of this study was the postoperative analgesic duration achieved. The secondary outcomes included morphine administration in the first 24 hours following caudal block an...

Research paper thumbnail of Transesterification of Methylbenzoate with Alcohols Catalyzed by Natural Phosphate

Synthetic Communications, 2006

Abstract Transesterification of methylbenzoate with various alcohols was catalyzed by natural pho... more Abstract Transesterification of methylbenzoate with various alcohols was catalyzed by natural phosphate with or without solvent in heterogeneous media. The molar ratio of alcohol/ester, solvent effect, and weight of catalyst effect have been studied. We have ...

Research paper thumbnail of Catalysis by phosphates: A simple and efficient procedure for transesterification reaction

Journal of Molecular Catalysis A: Chemical, 2006

Zinc chloride and potassium fluoride doped on natural phosphate (ZnCl 2 /NP and KF/NP) and sodium... more Zinc chloride and potassium fluoride doped on natural phosphate (ZnCl 2 /NP and KF/NP) and sodium nitrate modified natural phosphate (Na/NP) catalyze efficiently the transesterification reaction. The reaction proceeds in refluxing condition without remove of alcohol formed. Na/NP can be easily regenerated and reused.

Research paper thumbnail of Numerical Heat Transfer and Pressure Drop Investigation of Different Height Baffles Mounted Simultaneously in a 2-D Channel," Life Science Journal, 2013, 10 (2), pp 1711-1718

Life Science Journal

The objective of the current study is to numerically investigate the effect of different height b... more The objective of the current study is to numerically investigate the effect of different height baffles mounted simultaneously in a 2-dimensional channel on heat transfer and pressure drop. Three baffles of different height to channel ratios, / , of 0.167, 0.25, and 0.333, are used to form 9 different arrangements, or cases, of which seven cases have the same average baffle height, / of 0.167. Three of the 9 cases have equal height baffles. The Nusselt number ratio, / , and friction factor ratio, / , as functions of Reynolds number are to be studied. Two performance measures are applied, which are the standard deviation of temperature, , and the thermal performance enhancement factor,. The results shows that / , , and decrease with Re. There is a proportional relationship between / and Re. Using a short baffle in front and a tall baffle in the back leads to decreasing the difference between the maximum and minimum temperatures of the heater plate, hence, decreasing the average σ T values by up to 52%. Comparing the cases that have the same average baffle heights indicates that mounting tall baffles in front enhances / by 3%. For cases with equal average baffle heights, using baffles of equal height shows better performance from the point of view. [Mohamed Hamza, Abdullatif A. Gari. Numerical Heat Transfer and Pressure Drop Investigation of Different Height Baffles Mounted Simultaneously in a 2-D Channel.

Research paper thumbnail of Efficacy of Dexmedetomidine Versus Morphine as an Adjunct to Bupivacaine in Caudal Anesthesia for Pediatric Thoracic Surgeries: A Randomized Controlled Trial

Anesthesiology and Pain Medicine, 2021

Background: Caudal anesthesia is an effective method of pain management, which can be successfull... more Background: Caudal anesthesia is an effective method of pain management, which can be successfully employed to minimize post-thoracotomy pain in pediatric patients. However, its main disadvantage is the short postoperative analgesic period, which can be prolonged by the concurrent administration of one of many adjuvants. Objectives: This prospective randomized, blinded study aimed to compare the efficacy of dexmedetomidine versus morphine as adjuvants to bupivacaine in caudal anesthesia for thoracic surgeries in pediatric patients. Methods: Fifty patients were randomly allocated into two equal groups. To achieve caudal epidural block anesthesia, the patients in group M (n = 25) were administered morphine and bupivacaine, while group D (n = 25) received a mixture of dexmedetomidine and bupivacaine. The primary outcome of this study was the postoperative analgesic duration achieved. The secondary outcomes included morphine administration in the first 24 hours following caudal block an...

Research paper thumbnail of Transesterification of Methylbenzoate with Alcohols Catalyzed by Natural Phosphate

Synthetic Communications, 2006

Abstract Transesterification of methylbenzoate with various alcohols was catalyzed by natural pho... more Abstract Transesterification of methylbenzoate with various alcohols was catalyzed by natural phosphate with or without solvent in heterogeneous media. The molar ratio of alcohol/ester, solvent effect, and weight of catalyst effect have been studied. We have ...

Research paper thumbnail of Catalysis by phosphates: A simple and efficient procedure for transesterification reaction

Journal of Molecular Catalysis A: Chemical, 2006

Zinc chloride and potassium fluoride doped on natural phosphate (ZnCl 2 /NP and KF/NP) and sodium... more Zinc chloride and potassium fluoride doped on natural phosphate (ZnCl 2 /NP and KF/NP) and sodium nitrate modified natural phosphate (Na/NP) catalyze efficiently the transesterification reaction. The reaction proceeds in refluxing condition without remove of alcohol formed. Na/NP can be easily regenerated and reused.

Research paper thumbnail of Numerical Heat Transfer and Pressure Drop Investigation of Different Height Baffles Mounted Simultaneously in a 2-D Channel," Life Science Journal, 2013, 10 (2), pp 1711-1718

Life Science Journal

The objective of the current study is to numerically investigate the effect of different height b... more The objective of the current study is to numerically investigate the effect of different height baffles mounted simultaneously in a 2-dimensional channel on heat transfer and pressure drop. Three baffles of different height to channel ratios, / , of 0.167, 0.25, and 0.333, are used to form 9 different arrangements, or cases, of which seven cases have the same average baffle height, / of 0.167. Three of the 9 cases have equal height baffles. The Nusselt number ratio, / , and friction factor ratio, / , as functions of Reynolds number are to be studied. Two performance measures are applied, which are the standard deviation of temperature, , and the thermal performance enhancement factor,. The results shows that / , , and decrease with Re. There is a proportional relationship between / and Re. Using a short baffle in front and a tall baffle in the back leads to decreasing the difference between the maximum and minimum temperatures of the heater plate, hence, decreasing the average σ T values by up to 52%. Comparing the cases that have the same average baffle heights indicates that mounting tall baffles in front enhances / by 3%. For cases with equal average baffle heights, using baffles of equal height shows better performance from the point of view. [Mohamed Hamza, Abdullatif A. Gari. Numerical Heat Transfer and Pressure Drop Investigation of Different Height Baffles Mounted Simultaneously in a 2-D Channel.