mo sharif - Academia.edu (original) (raw)

Papers by mo sharif

Research paper thumbnail of Interfacial reaction and dissolution behavior of Cu substrate in molten Sn3.8Ag0.7Cu in the presence of Mo nanoparticles

Soldering & Surface Mount Technology, 2011

Miniaturization of electronic devices, especially those applying ball grid array package and flip... more Miniaturization of electronic devices, especially those applying ball grid array package and flip chip, demands better solder performance. Previously used Sn-Pb solder is now being replaced by lead-free solder in the electronics industry, as lead is harmful to the environment. In 2000, the National Electronic Manufacturing Initiative recommended the replacement of eutectic Sn-Pb solder by near eutectic Sn-Ag-Cu alloys. However, these solder alloys cannot guarantee the required performance especially with finer pitches, due to their demerits such as higher diffusivity and softening nature (Yeth et al., 2002).

Research paper thumbnail of Alloying of MoSi 2 for improved mechanical properties

Intermetallics, 2001

Effects of alloying on mechanical properties of solidification processed polycrystalline MoSi 2 ,... more Effects of alloying on mechanical properties of solidification processed polycrystalline MoSi 2 , ternary (Mo, 2.5 at.% Re)Si 2 , Mo(2 at.% Al, Si) 2 , (Mo, 1 at.% Nb)Si 2 , and quaternary (Mo, 1 at.% Re)( 2 at.% Al, Si) 2 alloys were evaluated by microhardness testing at room temperature and compression testing at elevated temperatures. Alloying with 2.5 at.% Re resulted in an anomalously high solid solution hardening in MoSi 2 , while alloying with 2 at.% Al lowered the brittle-to-ductile transition temperature, in compression, of polycrystalline MoSi 2 from 900 o C to 425 o C. Similar to the effects observed in the quaternary (Mo, 1 at.% Re)(2 at.% Al, Si) 2 alloy, 1 at.% Nb containing samples exhibited concurrent enhanced ambient temperature ductility and higher elevated temperature strength compared to pure MoSi 2 . The effects of alloying MoSi 2 with 2.5 at.% Re, 1 at.% Re+2 at.% Al, and 1 at.% Nb on hardness and yield strength are discussed. #

Research paper thumbnail of X-ray emission scaling law from a plasma focus with different anode tip materials (Cu, Mo, and W

Journal of Applied Physics, 2006

Research paper thumbnail of Study of molybdenum K-series line radiation emission from a low energy plasma focus

Physics Letters A, 2002

K-series line radiation emission of Mo and Cu from a low energy Mather-type plasma focus is inves... more K-series line radiation emission of Mo and Cu from a low energy Mather-type plasma focus is investigated. Quantrad Si pin diodes are employed as time resolved X-ray detectors, where as a pin hole camera is used for time integrated analysis. The measurable X-ray flux for hydrogen is observed in the pressure range of 0.5-3.5 mbar. Mo and Cu K-line radiation emission in this geometry has the highest values of about 0.05 J/sr and 0.17 J/sr, respectively at a filling pressure of 2.0 mbar. The corresponding efficiencies are 0.03% and 0.09%, respectively. Total X-ray emission and efficiency in 4π-geometry are also obtained with values 4.12 J and 0.18% at 2.0 mbar. The Mo K-line radiation emission may result due to interaction of energetic electron beam emitted from the focus region with the molybdenum insert.

Research paper thumbnail of Microscopic Change in Macroscopically Normal Equine Cartilage from Osteoarthritic Joints

Connective Tissue Research, 2006

The objective of this study was to assess whether macroscopically normal articular cartilage take... more The objective of this study was to assess whether macroscopically normal articular cartilage taken from joints containing focal osteoarthritic lesions is histologically similar to articular cartilage taken from macroscopically normal joints. Metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints were obtained from 10 horses following euthanasia. Gross articular cartilage damage was scored and the cartilage assigned to one of two groups: (1) macroscopically normal cartilage from normal joints (control) and (2) macroscopically normal cartilage from diseased joints in which there were focal osteoarthritic lesions. Chondrocytes expressing specific cytokines and cytokine receptors were identified by immunohistochemistry. The total number of chondrocytes, and percentage of chondrocytes positive for these cytokines and receptors, was recorded in the superficial, middle, and deep cartilage zones. There was a significant increase in the expression of interleukin-1beta in the superficial and middle zones and interleukin-18 receptor in the superficial zone in Group 2 compared with Group 1 control samples. A significant positive correlation also was found between the grade of osteoarthritis and the percentage of chondrocytes positive for interleukin-1beta in the superficial and middle zones, and for interleukin-18 and interleukin-18R in the superficial zone. There was a significant increase in histology score for glycosaminoglycan loss in Group 2 compared with that in Group 1. In joints with focal osteoarthritis lesions, all the articular cartilage, even if macroscopically apparently normal, may have microscopic changes associated with osteoarthritis.

Research paper thumbnail of Interfacial reaction and dissolution behavior of Cu substrate in molten Sn3.8Ag0.7Cu in the presence of Mo nanoparticles

Soldering & Surface Mount Technology, 2011

Miniaturization of electronic devices, especially those applying ball grid array package and flip... more Miniaturization of electronic devices, especially those applying ball grid array package and flip chip, demands better solder performance. Previously used Sn-Pb solder is now being replaced by lead-free solder in the electronics industry, as lead is harmful to the environment. In 2000, the National Electronic Manufacturing Initiative recommended the replacement of eutectic Sn-Pb solder by near eutectic Sn-Ag-Cu alloys. However, these solder alloys cannot guarantee the required performance especially with finer pitches, due to their demerits such as higher diffusivity and softening nature (Yeth et al., 2002).

Research paper thumbnail of Alloying of MoSi 2 for improved mechanical properties

Intermetallics, 2001

Effects of alloying on mechanical properties of solidification processed polycrystalline MoSi 2 ,... more Effects of alloying on mechanical properties of solidification processed polycrystalline MoSi 2 , ternary (Mo, 2.5 at.% Re)Si 2 , Mo(2 at.% Al, Si) 2 , (Mo, 1 at.% Nb)Si 2 , and quaternary (Mo, 1 at.% Re)( 2 at.% Al, Si) 2 alloys were evaluated by microhardness testing at room temperature and compression testing at elevated temperatures. Alloying with 2.5 at.% Re resulted in an anomalously high solid solution hardening in MoSi 2 , while alloying with 2 at.% Al lowered the brittle-to-ductile transition temperature, in compression, of polycrystalline MoSi 2 from 900 o C to 425 o C. Similar to the effects observed in the quaternary (Mo, 1 at.% Re)(2 at.% Al, Si) 2 alloy, 1 at.% Nb containing samples exhibited concurrent enhanced ambient temperature ductility and higher elevated temperature strength compared to pure MoSi 2 . The effects of alloying MoSi 2 with 2.5 at.% Re, 1 at.% Re+2 at.% Al, and 1 at.% Nb on hardness and yield strength are discussed. #

Research paper thumbnail of X-ray emission scaling law from a plasma focus with different anode tip materials (Cu, Mo, and W

Journal of Applied Physics, 2006

Research paper thumbnail of Study of molybdenum K-series line radiation emission from a low energy plasma focus

Physics Letters A, 2002

K-series line radiation emission of Mo and Cu from a low energy Mather-type plasma focus is inves... more K-series line radiation emission of Mo and Cu from a low energy Mather-type plasma focus is investigated. Quantrad Si pin diodes are employed as time resolved X-ray detectors, where as a pin hole camera is used for time integrated analysis. The measurable X-ray flux for hydrogen is observed in the pressure range of 0.5-3.5 mbar. Mo and Cu K-line radiation emission in this geometry has the highest values of about 0.05 J/sr and 0.17 J/sr, respectively at a filling pressure of 2.0 mbar. The corresponding efficiencies are 0.03% and 0.09%, respectively. Total X-ray emission and efficiency in 4π-geometry are also obtained with values 4.12 J and 0.18% at 2.0 mbar. The Mo K-line radiation emission may result due to interaction of energetic electron beam emitted from the focus region with the molybdenum insert.

Research paper thumbnail of Microscopic Change in Macroscopically Normal Equine Cartilage from Osteoarthritic Joints

Connective Tissue Research, 2006

The objective of this study was to assess whether macroscopically normal articular cartilage take... more The objective of this study was to assess whether macroscopically normal articular cartilage taken from joints containing focal osteoarthritic lesions is histologically similar to articular cartilage taken from macroscopically normal joints. Metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints were obtained from 10 horses following euthanasia. Gross articular cartilage damage was scored and the cartilage assigned to one of two groups: (1) macroscopically normal cartilage from normal joints (control) and (2) macroscopically normal cartilage from diseased joints in which there were focal osteoarthritic lesions. Chondrocytes expressing specific cytokines and cytokine receptors were identified by immunohistochemistry. The total number of chondrocytes, and percentage of chondrocytes positive for these cytokines and receptors, was recorded in the superficial, middle, and deep cartilage zones. There was a significant increase in the expression of interleukin-1beta in the superficial and middle zones and interleukin-18 receptor in the superficial zone in Group 2 compared with Group 1 control samples. A significant positive correlation also was found between the grade of osteoarthritis and the percentage of chondrocytes positive for interleukin-1beta in the superficial and middle zones, and for interleukin-18 and interleukin-18R in the superficial zone. There was a significant increase in histology score for glycosaminoglycan loss in Group 2 compared with that in Group 1. In joints with focal osteoarthritis lesions, all the articular cartilage, even if macroscopically apparently normal, may have microscopic changes associated with osteoarthritis.