umar hayat - Academia.edu (original) (raw)
Related Authors
International Islamic University . Islambad. Pakistan
International Islamic University . Islambad. Pakistan
Uploads
Papers by umar hayat
Physics Letters A, 2008
In this investigation, the peristaltic flow of a third order fluid in an asymmetric channel is co... more In this investigation, the peristaltic flow of a third order fluid in an asymmetric channel is considered in the presence of a slip condition. The series solution of the stream function and longitudinal pressure gradient is given under long wave length and low Reynolds number approximations. Pressure rise and frictional forces per wave length are analyzed through numerical integration. Pumping and trapping phenomena are examined and the obtained results are compared with those of no-slip condition. Comparison is made with the results of no-slip and viscous fluid cases.
Journal of Electroanalytical Chemistry, 1987
The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent conducting po... more The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent conducting polymer film at the electrode. Conductivity measurements on pressed pellets of this polymer give a room temperature conductivity of 10 S cm-'. The polymer can be cycled between 25 and 2OO'C without deterioration in the conductivity. Preliminary SEM/EDS studies suggest that there is one BFi counter ion for every four monomer units in the oxidised polymer film. 0022-0728/87/$03.50 0 1987 Elsevier Sequoia S.A.
Journal of Polymer Science Part A-polymer Chemistry, 1988
The surface compositions of various polymeric films, grown electrochemically on platinum foils, h... more The surface compositions of various polymeric films, grown electrochemically on platinum foils, have been investigated by energy-dispersive x-ray analysis in conjunction with scanning electron microscopy (SEM/EDS). Comparison of the relative area ratios of peaks for the C and N Kemission lines show that the EDS may be used to study the surface composition of polymers. The evidence presented strongly suggests that there is limited structural degradation and the elemental composition is not changed under the electron beam at relatively low accelerating voltages. This technique statistically samples the repeat units of the polymer. For samples grown in both aqueous and nonaqueous solutions. SEM/EDS provides evidence for extensive contamination with oxygen.
The surface compositions of various polymeric films, grown electrochemically on platinum foils, h... more The surface compositions of various polymeric films, grown electrochemically on platinum foils, have been investigated by energy-dispersive x-ray analysis in conjunction with scanning electron micrmcopy (SEM/EDS). Comparison of the relative mea ratios of peaks for the C and N Kam lines show that the EDS may be used to study the surface composition of polymers. The evidence presented strongly suggests that there is limited structural degradation and the element a l composition is not changed under the electron beam at relatively low accelerating voltages. This technique statistically samples the repeat units of the polymer. For samples grown in both aqueous and nonaqueous solutions. SEM/EDS provides evidence for extensive contamination with oxygen.
Journal of Macromolecular Science, Part A, 1994
A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacryl... more A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacrylate (PMMA)] can be achieved by polymerizing organosilane in a low-temperature polymerization process. The substrate surface can be initially modified with hydrophilic functionalities in a radio-frequency plasma of argon/water vapor mixture in the pressure range 0.05-0.15 mbar to attach hydroxyl functionalities covalently to the substrate surface, which act as “anchorage
Journal of Macromolecular Science, Part A, 1994
A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacryl... more A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacrylate (PMMA)] can be achieved by polymerizing organosilane in a low-temperature polymerization process. The substrate surface can be initially modified with hydrophilic functionalities in a radio-frequency plasma of argon/water vapor mixture in the pressure range 0.05-0.15 mbar to attach hydroxyl functionalities covalently to the substrate surface, which act as “anchorage
Physics Letters A, 2008
In this investigation, the peristaltic flow of a third order fluid in an asymmetric channel is co... more In this investigation, the peristaltic flow of a third order fluid in an asymmetric channel is considered in the presence of a slip condition. The series solution of the stream function and longitudinal pressure gradient is given under long wave length and low Reynolds number approximations. Pressure rise and frictional forces per wave length are analyzed through numerical integration. Pumping and trapping phenomena are examined and the obtained results are compared with those of no-slip condition. Comparison is made with the results of no-slip and viscous fluid cases.
Journal of Electroanalytical Chemistry, 1987
The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent conducting po... more The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent conducting polymer film at the electrode. Conductivity measurements on pressed pellets of this polymer give a room temperature conductivity of 10 S cm-'. The polymer can be cycled between 25 and 2OO'C without deterioration in the conductivity. Preliminary SEM/EDS studies suggest that there is one BFi counter ion for every four monomer units in the oxidised polymer film. 0022-0728/87/$03.50 0 1987 Elsevier Sequoia S.A.
Journal of Polymer Science Part A-polymer Chemistry, 1988
The surface compositions of various polymeric films, grown electrochemically on platinum foils, h... more The surface compositions of various polymeric films, grown electrochemically on platinum foils, have been investigated by energy-dispersive x-ray analysis in conjunction with scanning electron microscopy (SEM/EDS). Comparison of the relative area ratios of peaks for the C and N Kemission lines show that the EDS may be used to study the surface composition of polymers. The evidence presented strongly suggests that there is limited structural degradation and the elemental composition is not changed under the electron beam at relatively low accelerating voltages. This technique statistically samples the repeat units of the polymer. For samples grown in both aqueous and nonaqueous solutions. SEM/EDS provides evidence for extensive contamination with oxygen.
The surface compositions of various polymeric films, grown electrochemically on platinum foils, h... more The surface compositions of various polymeric films, grown electrochemically on platinum foils, have been investigated by energy-dispersive x-ray analysis in conjunction with scanning electron micrmcopy (SEM/EDS). Comparison of the relative mea ratios of peaks for the C and N Kam lines show that the EDS may be used to study the surface composition of polymers. The evidence presented strongly suggests that there is limited structural degradation and the element a l composition is not changed under the electron beam at relatively low accelerating voltages. This technique statistically samples the repeat units of the polymer. For samples grown in both aqueous and nonaqueous solutions. SEM/EDS provides evidence for extensive contamination with oxygen.
Journal of Macromolecular Science, Part A, 1994
A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacryl... more A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacrylate (PMMA)] can be achieved by polymerizing organosilane in a low-temperature polymerization process. The substrate surface can be initially modified with hydrophilic functionalities in a radio-frequency plasma of argon/water vapor mixture in the pressure range 0.05-0.15 mbar to attach hydroxyl functionalities covalently to the substrate surface, which act as “anchorage
Journal of Macromolecular Science, Part A, 1994
A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacryl... more A well-adhered and abrasion-resistant coating on a typical optical substrate [polymethylmethacrylate (PMMA)] can be achieved by polymerizing organosilane in a low-temperature polymerization process. The substrate surface can be initially modified with hydrophilic functionalities in a radio-frequency plasma of argon/water vapor mixture in the pressure range 0.05-0.15 mbar to attach hydroxyl functionalities covalently to the substrate surface, which act as “anchorage