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Ceramics International, 2006
Mechanical and tribological properties of electrospun fiber fabrics are of paramount importance t... more Mechanical and tribological properties of electrospun fiber fabrics are of paramount importance to their utility as components in a large number of applications. Postspin heat treatment assisted with static pressure has been used to enhance the properties of electrospun fabrics and to activate its high surface energy. High-resolution transmission electron microscopy (HRTEM) showed a formation of graphitic structure of 9.5-nm crystallite sizes that has been calculated from Raman breathing modes. Hot-pressed multi-walled carbon nanotubes (MWCNTs)/carbon fabric with 130±32-nm fibril diameters showed an outstanding flexibility and strength. Also, adding MWCNTs enhanced the fabric tensile strength (from 40 to 60 MPa) and lowered the fabric coefficient of friction (COF) (from 1.70 to 0.15) and its abrasive mass loss (0.2 mg has been achieved). The hot-pressed electrospun MWCNTs/carbon nanofibril composite fabrics can be considered as a good candidate, by controlling fabric MWCNT weight percent, for both journal bearing (COF below 0.4) and brake pad (COF from 0.4 to 0.7) applications.
Chinese Chemical Letters, 2018
Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this w... more Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work, cobalt oxide nanoparticles (NPs) supported on porous carbon (CoO x @CN) were fabricated by one-pot method and the hybrids could efficiently and selectively hydrogenate phenol to cyclohexanol with a high yield of 98%. The high catalytic performance of CoO x @CN was associate with the high surface area (340 m 2 /g) and uniformly dispersed NPs. Furthurmore, by detailed analysing the relationship between catalytic activity and catalysts composition, it clearly indicated that the Co 3 O 4 in CoO x @CN played an important role for the adsorption and activation of phenol and the in situ gernerated Co was responsible for hydrogen adsorption and dissociation. These findings provide a fundamental insight into the real active sites in hydrogenation of phenol using Co-based catalysts.
The effect of milling time on the microstructure and mechanical properties of Ti-6Al-4Fe alloys
Materials Today Communications
The effect of milling time on the microstructure and mechanical properties of Ti-6Al-4Fe alloys
Replacement of toxic and expensive vanadium (V) in medical grade titanium alloys with cheaper and... more Replacement of toxic and expensive vanadium (V) in medical grade titanium alloys with cheaper and non-toxic elements such as iron (Fe) or niobium (Nb), is an important step forward in developing safer and less expensive biomaterials. Evaluating the effect of different process parameters such as the milling time on the properties of these newly developed alloys helps in understanding and controlling their behavior. Hence, in this study, the influence of ball-milling duration (2, 6, 8, 12 and 18 h) on crystalline structure, phase evolution, densification, and mechanical characteristics of biomedical nanocrystalline Ti-6Al-4Fe (wt. %) alloys is investigated. X-ray diffraction (XRD) confirmed that after 6 h of milling, aluminum (Al) and Fe completely dissolved into Ti matrix to form a solid solution of Ti (Al, Fe). XRD further revealed that the crystallite size decreased from 56 to 30 nm and the micro-strain increased with an increase in milling time. A decrease in porosity along with a...
Ceramics International, 2006
Mechanical and tribological properties of electrospun fiber fabrics are of paramount importance t... more Mechanical and tribological properties of electrospun fiber fabrics are of paramount importance to their utility as components in a large number of applications. Postspin heat treatment assisted with static pressure has been used to enhance the properties of electrospun fabrics and to activate its high surface energy. High-resolution transmission electron microscopy (HRTEM) showed a formation of graphitic structure of 9.5-nm crystallite sizes that has been calculated from Raman breathing modes. Hot-pressed multi-walled carbon nanotubes (MWCNTs)/carbon fabric with 130±32-nm fibril diameters showed an outstanding flexibility and strength. Also, adding MWCNTs enhanced the fabric tensile strength (from 40 to 60 MPa) and lowered the fabric coefficient of friction (COF) (from 1.70 to 0.15) and its abrasive mass loss (0.2 mg has been achieved). The hot-pressed electrospun MWCNTs/carbon nanofibril composite fabrics can be considered as a good candidate, by controlling fabric MWCNT weight percent, for both journal bearing (COF below 0.4) and brake pad (COF from 0.4 to 0.7) applications.
Chinese Chemical Letters, 2018
Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this w... more Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work, cobalt oxide nanoparticles (NPs) supported on porous carbon (CoO x @CN) were fabricated by one-pot method and the hybrids could efficiently and selectively hydrogenate phenol to cyclohexanol with a high yield of 98%. The high catalytic performance of CoO x @CN was associate with the high surface area (340 m 2 /g) and uniformly dispersed NPs. Furthurmore, by detailed analysing the relationship between catalytic activity and catalysts composition, it clearly indicated that the Co 3 O 4 in CoO x @CN played an important role for the adsorption and activation of phenol and the in situ gernerated Co was responsible for hydrogen adsorption and dissociation. These findings provide a fundamental insight into the real active sites in hydrogenation of phenol using Co-based catalysts.
The effect of milling time on the microstructure and mechanical properties of Ti-6Al-4Fe alloys
Materials Today Communications
The effect of milling time on the microstructure and mechanical properties of Ti-6Al-4Fe alloys
Replacement of toxic and expensive vanadium (V) in medical grade titanium alloys with cheaper and... more Replacement of toxic and expensive vanadium (V) in medical grade titanium alloys with cheaper and non-toxic elements such as iron (Fe) or niobium (Nb), is an important step forward in developing safer and less expensive biomaterials. Evaluating the effect of different process parameters such as the milling time on the properties of these newly developed alloys helps in understanding and controlling their behavior. Hence, in this study, the influence of ball-milling duration (2, 6, 8, 12 and 18 h) on crystalline structure, phase evolution, densification, and mechanical characteristics of biomedical nanocrystalline Ti-6Al-4Fe (wt. %) alloys is investigated. X-ray diffraction (XRD) confirmed that after 6 h of milling, aluminum (Al) and Fe completely dissolved into Ti matrix to form a solid solution of Ti (Al, Fe). XRD further revealed that the crystallite size decreased from 56 to 30 nm and the micro-strain increased with an increase in milling time. A decrease in porosity along with a...