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Papers by Solomon Samuel
Microporous and Mesoporous Materials, 2009
A convenient and environmentally friendly synthesis of monodisperse and mesoporous silica nanosph... more A convenient and environmentally friendly synthesis of monodisperse and mesoporous silica nanospheres by the addition of sugar molecules like glucose and fructose as templates into the Stober process is presented. The nonsurfactant templates can be extracted by simple extraction with water, thus circumventing the requirement of high temperature calcinations which tend to affect textural properties. Nitrogen adsorption-desorption, scanning electron microscopy (SEM), dynamic light scattering (DLS) and thermogravimetric analysis (TGA) were employed for the characterization of these spheres. Results indicate that the particle size can be tuned from 50 to 1140 nm by simply controlling the concentration of fructose in the reaction. A notable change in surface area with increasing fructose content was also observed. The effect of replacing fructose with glucose or maltose on the particle size and surface area of the spheres was also examined. These spherical silicas could find potential applications in enzyme encapsulation, as stationary phase in chromatography and as fillers in polymer composites.
Dental Materials, 2009
d e n t a l m a t e r i a l s 2 5 ( 2 0 0 9 ) 296-301 a v a i l a b l e a t w w w . s c i e n c e... more d e n t a l m a t e r i a l s 2 5 ( 2 0 0 9 ) 296-301 a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . i n t l . e l s e v i e r h e a l t h . c o m / j o u r n a l s / d e m a Mechanical properties of experimental dental composites containing a combination of mesoporous and nonporous spherical silica as fillers Non-surfactant Template Micromechanical interphase bonding a b s t r a c t
Bone is a self-repairing structural material, which adapts its material properties and shape in r... more Bone is a self-repairing structural material, which adapts its material properties and shape in response to a number of factors. Healthy bones do not develop spontaneous fractures during voluntary physical activities of life. However, an imbalance between bone strength and the mechanical loads placed on the bones can lead to bone fractures. Bone health is affected by a number of factors including age, gender, physical activity, systemic diseases, and drug treatment for various diseases. This chapter will discuss bone design as it relates to fracture resistance and locomotion, fracture prediction techniques, and fracture prevention.
Journal of Materials Research, 2008
ABSTRACT The presence of low-molecular-weight by-products is a major problem in poly[2-hydroxethy... more ABSTRACT The presence of low-molecular-weight by-products is a major problem in poly[2-hydroxethyl methacrylate (HEMA)-silica] hybrids prepared using sol-gel synthesis. Low-molecular-weight by-products have a detrimental effect on the optical transparency, and mechanical and storage properties of poly(HEMA-silica) hybrids. To solve this problem, a new sol-gel synthesis procedure was developed to prepare organic–inorganic hybrids. Glycidyl methacrylate (GMA) was used as a comonomer to form poly(HEMA-GMA-silica) (PHGS) hybrids. In addition to forming a copolymer, GMA has two more functions. It facilitates the removal of almost all of the low-molecular-weight by-product molecules formed during sol-gel synthesis and also prevents further condensation of free silanol groups during the polymerization, storage, and use. The mechanical properties of PHGS hybrids were evaluated by using compression testing. The mechanical properties of PHGS hybrids were higher compared to Plexiglas G poly(methyl methacrylate), and the hybrids can be synthesized with reproducible mechanical properties.
Microporous and Mesoporous Materials, 2009
A convenient and environmentally friendly synthesis of monodisperse and mesoporous silica nanosph... more A convenient and environmentally friendly synthesis of monodisperse and mesoporous silica nanospheres by the addition of sugar molecules like glucose and fructose as templates into the Stober process is presented. The nonsurfactant templates can be extracted by simple extraction with water, thus circumventing the requirement of high temperature calcinations which tend to affect textural properties. Nitrogen adsorption-desorption, scanning electron microscopy (SEM), dynamic light scattering (DLS) and thermogravimetric analysis (TGA) were employed for the characterization of these spheres. Results indicate that the particle size can be tuned from 50 to 1140 nm by simply controlling the concentration of fructose in the reaction. A notable change in surface area with increasing fructose content was also observed. The effect of replacing fructose with glucose or maltose on the particle size and surface area of the spheres was also examined. These spherical silicas could find potential applications in enzyme encapsulation, as stationary phase in chromatography and as fillers in polymer composites.
Dental Materials, 2009
d e n t a l m a t e r i a l s 2 5 ( 2 0 0 9 ) 296-301 a v a i l a b l e a t w w w . s c i e n c e... more d e n t a l m a t e r i a l s 2 5 ( 2 0 0 9 ) 296-301 a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . i n t l . e l s e v i e r h e a l t h . c o m / j o u r n a l s / d e m a Mechanical properties of experimental dental composites containing a combination of mesoporous and nonporous spherical silica as fillers Non-surfactant Template Micromechanical interphase bonding a b s t r a c t
Bone is a self-repairing structural material, which adapts its material properties and shape in r... more Bone is a self-repairing structural material, which adapts its material properties and shape in response to a number of factors. Healthy bones do not develop spontaneous fractures during voluntary physical activities of life. However, an imbalance between bone strength and the mechanical loads placed on the bones can lead to bone fractures. Bone health is affected by a number of factors including age, gender, physical activity, systemic diseases, and drug treatment for various diseases. This chapter will discuss bone design as it relates to fracture resistance and locomotion, fracture prediction techniques, and fracture prevention.
Journal of Materials Research, 2008
ABSTRACT The presence of low-molecular-weight by-products is a major problem in poly[2-hydroxethy... more ABSTRACT The presence of low-molecular-weight by-products is a major problem in poly[2-hydroxethyl methacrylate (HEMA)-silica] hybrids prepared using sol-gel synthesis. Low-molecular-weight by-products have a detrimental effect on the optical transparency, and mechanical and storage properties of poly(HEMA-silica) hybrids. To solve this problem, a new sol-gel synthesis procedure was developed to prepare organic–inorganic hybrids. Glycidyl methacrylate (GMA) was used as a comonomer to form poly(HEMA-GMA-silica) (PHGS) hybrids. In addition to forming a copolymer, GMA has two more functions. It facilitates the removal of almost all of the low-molecular-weight by-product molecules formed during sol-gel synthesis and also prevents further condensation of free silanol groups during the polymerization, storage, and use. The mechanical properties of PHGS hybrids were evaluated by using compression testing. The mechanical properties of PHGS hybrids were higher compared to Plexiglas G poly(methyl methacrylate), and the hybrids can be synthesized with reproducible mechanical properties.