Magnesium stands for a very attractive material for biodegradable stents because of its natural p... more Magnesium stands for a very attractive material for biodegradable stents because of its natural process and its steady disintegration into the human body by a corrosion process. The objective of the present work is to investigate the effect of the thickness on mechanical properties of the magnesium stent design. A nonlinear transient finite element simulation has been performed to analyze the influence of various thicknesses (from 50µm to 110µm with the increment of 30µm) on the behavior of a magnesium coronary stent. The model was constrained symmetrically to ensure that any virtual rigid movement does not occur during the process of coronary stent expansion. The transient load is applied in three steps in the inner surface of the stent. Four mechanical properties are studied by mathematical modeling with determination of: (1) stent deployment pressure; (2) the intrinsic elastic recoil of the material used; (3) the stent longitudinal recoil; (4) and the stress maps. The results indicate the potential application of magnesium stent and the effect of the thickness on the behavior of magnesium stent design and material.
Recently, the fiber reinforced composite embedded with visco-elastic layer has received great att... more Recently, the fiber reinforced composite embedded with visco-elastic layer has received great attention because of its good damping capability. Damping is an important feature for dynamic behaviour of composite structures, which alleviates the resonant vibrations and thus prolongs the service life of structures under fatigue loading or impact. The present paper deals with the dynamic response of a 3D composite structure embedded with visco-elastic layer. The modal analysis, harmonic analysis and transient analysis are carried out respectively. The amplitude of z-displacement of a specific node on the bottom reduces quickly due to the high damping of the visco-elastic layer.
A stent is a medical device designed to serve as a temporary or permanent internal scaffold to ma... more A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.
Magnesium stands for a very attractive material for biodegradable stents because of its natural p... more Magnesium stands for a very attractive material for biodegradable stents because of its natural process and its steady disintegration into the human body by a corrosion process. The objective of the present work is to investigate the effect of the thickness on mechanical properties of the magnesium stent design. A nonlinear transient finite element simulation has been performed to analyze the influence of various thicknesses (from 50µm to 110µm with the increment of 30µm) on the behavior of a magnesium coronary stent. The model was constrained symmetrically to ensure that any virtual rigid movement does not occur during the process of coronary stent expansion. The transient load is applied in three steps in the inner surface of the stent. Four mechanical properties are studied by mathematical modeling with determination of: (1) stent deployment pressure; (2) the intrinsic elastic recoil of the material used; (3) the stent longitudinal recoil; (4) and the stress maps. The results ind...
Recently, the fiber reinforced composite embedded with visco-elastic layer has received great att... more Recently, the fiber reinforced composite embedded with visco-elastic layer has received great attention because of its good damping capability. Damping is an important feature for dynamic behaviour of composite structures, which alleviates the resonant vibrations and thus prolongs the service life of structures under fatigue loading or impact. The present paper deals with the dynamic response of a 3D composite structure embedded with visco-elastic layer. The modal analysis, harmonic analysis and transient analysis are carried out respectively. The amplitude of z-displacement of a specific node on the bottom reduces quickly due to the high damping of the visco-elastic layer.
The work reported in this paper describes the behavior and prediction of damping properties of th... more The work reported in this paper describes the behavior and prediction of damping properties of the 3D composite laminated engine mount shell structure. The shell structure has a shape of box with four vertical and two horizontal plates with the thickness of 15mm and 20mm respectively. For more accurate prediction of the structural behavior, many researchers have incorporated the time dependent property of the material into their field of studies. In this article the finite element approach utilizes the concept of viscoelastic damping, which is carried out by direct integration. This paper describes the potential application of composite material as a damper device because of its damping, high stiffness and low weight properties, which favor the use as engine mount in submarine and ships where weight is the highest priority.
Niobium and nitrogen co-doped SrTiO3 possessing excellent visible light responsive photocatalytic... more Niobium and nitrogen co-doped SrTiO3 possessing excellent visible light responsive photocatalytic activity was successfully synthesized by microwave-assisted solvothermal reaction using SrCl2.6H2O, Ti(OC3H7)4, NbCl5 and hexamethylenetetramine in KOH aqueous solution. The photocatalytic activity was determined by DeNOx ability using LED lamps with the wavelengths of 627 nm (red), 530 nm (green), 445 nm (blue) and 390 nm (UV). The photocatalytic activity of SrTiO3 for DeNOx ability in visible light region could be improved by co-doping Nb5+ and N3-. The excellent visible light photocatalytic activity of this substance may be due to the generation of a new band gap that enables to absorb visible light and decrease in the lattice defects which acts as a recombination center of photoinduced electrons and holes.
Biodegradable magnesium alloy stents have gained increasing interest in the past years due to the... more Biodegradable magnesium alloy stents have gained increasing interest in the past years due to their potential prospect. Magnesium alloy is brittle compared with stainless steel. This means it has less elongation than other stent materials and it may cause strut break under large deformation. In this paper, a finite element model for magnesium alloy stent is studied to simulate the mechanical behavior of the stent. It is composed of 1.5mm in inner diameter, 7mm length, 80µm thickness and 110µm in cross-sectional width. Six mechanical properties have been studied by mathematical modeling with determination of: (1) stent deployment pressure; (2) the intrinsic elastic recoil of the material used; (3) the stent foreshortening; (4) the stent coverage area, (5) the stent flexibility; and (6) the stress maps.
A stent is a medical device designed to serve as a temporary or permanent internal scaffold to ma... more A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.
Biodegradable polymer scaffolds have played a
significant role in wide range of tissue engineeri... more Biodegradable polymer scaffolds have played a
significant role in wide range of tissue engineering application
such as bone scaffolds since the last decade. The aim
of this article is to provide the comprehensive overview of
biocompatible and biodegradable polymer materials and
composite materials with their advantages and drawbacks
in the application of biomaterial scaffolds, furthermore the
properties and degradation criteria of the biomaterials are
discussed in this review.
The work reported in this paper describes the behavior and prediction of damping properties of th... more The work reported in this paper describes the behavior and prediction of damping properties of the 3D composite laminated engine mount shell structure. The shell structure has a shape of box with four vertical and two horizontal plates with the thickness of 15mm and 20mm respectively. For more accurate prediction of the structural behavior, many researchers have incorporated the time dependent property of the material into their field of studies. In this article the
finite element approach utilizes the concept of viscoelastic damping, which is carried out by direct integration. This paper describes the potential application of composite material as a damper device because of its damping, high stiffness and low weight properties, which favor the use as engine mount
in submarine and ships where weight is the highest priority.
Magnesium stands for a very attractive material for biodegradable stents because of its natural p... more Magnesium stands for a very attractive material for biodegradable stents because of its natural process and its steady disintegration into the human body by a corrosion process. The objective of the present work is to investigate the effect of the thickness on mechanical properties of the magnesium stent design. A nonlinear transient finite element simulation has been performed to analyze the influence of various thicknesses (from 50µm to 110µm with the increment of 30µm) on the behavior of a magnesium coronary stent. The model was constrained symmetrically to ensure that any virtual rigid movement does not occur during the process of coronary stent expansion. The transient load is applied in three steps in the inner surface of the stent. Four mechanical properties are studied by mathematical modeling with determination of: (1) stent deployment pressure; (2) the intrinsic elastic recoil of the material used; (3) the stent longitudinal recoil; (4) and the stress maps. The results indicate the potential application of magnesium stent and the effect of the thickness on the behavior of magnesium stent design and material.
Recently, the fiber reinforced composite embedded with visco-elastic layer has received great att... more Recently, the fiber reinforced composite embedded with visco-elastic layer has received great attention because of its good damping capability. Damping is an important feature for dynamic behaviour of composite structures, which alleviates the resonant vibrations and thus prolongs the service life of structures under fatigue loading or impact. The present paper deals with the dynamic response of a 3D composite structure embedded with visco-elastic layer. The modal analysis, harmonic analysis and transient analysis are carried out respectively. The amplitude of z-displacement of a specific node on the bottom reduces quickly due to the high damping of the visco-elastic layer.
A stent is a medical device designed to serve as a temporary or permanent internal scaffold to ma... more A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.
Magnesium stands for a very attractive material for biodegradable stents because of its natural p... more Magnesium stands for a very attractive material for biodegradable stents because of its natural process and its steady disintegration into the human body by a corrosion process. The objective of the present work is to investigate the effect of the thickness on mechanical properties of the magnesium stent design. A nonlinear transient finite element simulation has been performed to analyze the influence of various thicknesses (from 50µm to 110µm with the increment of 30µm) on the behavior of a magnesium coronary stent. The model was constrained symmetrically to ensure that any virtual rigid movement does not occur during the process of coronary stent expansion. The transient load is applied in three steps in the inner surface of the stent. Four mechanical properties are studied by mathematical modeling with determination of: (1) stent deployment pressure; (2) the intrinsic elastic recoil of the material used; (3) the stent longitudinal recoil; (4) and the stress maps. The results ind...
Recently, the fiber reinforced composite embedded with visco-elastic layer has received great att... more Recently, the fiber reinforced composite embedded with visco-elastic layer has received great attention because of its good damping capability. Damping is an important feature for dynamic behaviour of composite structures, which alleviates the resonant vibrations and thus prolongs the service life of structures under fatigue loading or impact. The present paper deals with the dynamic response of a 3D composite structure embedded with visco-elastic layer. The modal analysis, harmonic analysis and transient analysis are carried out respectively. The amplitude of z-displacement of a specific node on the bottom reduces quickly due to the high damping of the visco-elastic layer.
The work reported in this paper describes the behavior and prediction of damping properties of th... more The work reported in this paper describes the behavior and prediction of damping properties of the 3D composite laminated engine mount shell structure. The shell structure has a shape of box with four vertical and two horizontal plates with the thickness of 15mm and 20mm respectively. For more accurate prediction of the structural behavior, many researchers have incorporated the time dependent property of the material into their field of studies. In this article the finite element approach utilizes the concept of viscoelastic damping, which is carried out by direct integration. This paper describes the potential application of composite material as a damper device because of its damping, high stiffness and low weight properties, which favor the use as engine mount in submarine and ships where weight is the highest priority.
Niobium and nitrogen co-doped SrTiO3 possessing excellent visible light responsive photocatalytic... more Niobium and nitrogen co-doped SrTiO3 possessing excellent visible light responsive photocatalytic activity was successfully synthesized by microwave-assisted solvothermal reaction using SrCl2.6H2O, Ti(OC3H7)4, NbCl5 and hexamethylenetetramine in KOH aqueous solution. The photocatalytic activity was determined by DeNOx ability using LED lamps with the wavelengths of 627 nm (red), 530 nm (green), 445 nm (blue) and 390 nm (UV). The photocatalytic activity of SrTiO3 for DeNOx ability in visible light region could be improved by co-doping Nb5+ and N3-. The excellent visible light photocatalytic activity of this substance may be due to the generation of a new band gap that enables to absorb visible light and decrease in the lattice defects which acts as a recombination center of photoinduced electrons and holes.
Biodegradable magnesium alloy stents have gained increasing interest in the past years due to the... more Biodegradable magnesium alloy stents have gained increasing interest in the past years due to their potential prospect. Magnesium alloy is brittle compared with stainless steel. This means it has less elongation than other stent materials and it may cause strut break under large deformation. In this paper, a finite element model for magnesium alloy stent is studied to simulate the mechanical behavior of the stent. It is composed of 1.5mm in inner diameter, 7mm length, 80µm thickness and 110µm in cross-sectional width. Six mechanical properties have been studied by mathematical modeling with determination of: (1) stent deployment pressure; (2) the intrinsic elastic recoil of the material used; (3) the stent foreshortening; (4) the stent coverage area, (5) the stent flexibility; and (6) the stress maps.
A stent is a medical device designed to serve as a temporary or permanent internal scaffold to ma... more A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.
Biodegradable polymer scaffolds have played a
significant role in wide range of tissue engineeri... more Biodegradable polymer scaffolds have played a
significant role in wide range of tissue engineering application
such as bone scaffolds since the last decade. The aim
of this article is to provide the comprehensive overview of
biocompatible and biodegradable polymer materials and
composite materials with their advantages and drawbacks
in the application of biomaterial scaffolds, furthermore the
properties and degradation criteria of the biomaterials are
discussed in this review.
The work reported in this paper describes the behavior and prediction of damping properties of th... more The work reported in this paper describes the behavior and prediction of damping properties of the 3D composite laminated engine mount shell structure. The shell structure has a shape of box with four vertical and two horizontal plates with the thickness of 15mm and 20mm respectively. For more accurate prediction of the structural behavior, many researchers have incorporated the time dependent property of the material into their field of studies. In this article the
finite element approach utilizes the concept of viscoelastic damping, which is carried out by direct integration. This paper describes the potential application of composite material as a damper device because of its damping, high stiffness and low weight properties, which favor the use as engine mount
in submarine and ships where weight is the highest priority.
Uploads
significant role in wide range of tissue engineering application
such as bone scaffolds since the last decade. The aim
of this article is to provide the comprehensive overview of
biocompatible and biodegradable polymer materials and
composite materials with their advantages and drawbacks
in the application of biomaterial scaffolds, furthermore the
properties and degradation criteria of the biomaterials are
discussed in this review.
finite element approach utilizes the concept of viscoelastic damping, which is carried out by direct integration. This paper describes the potential application of composite material as a damper device because of its damping, high stiffness and low weight properties, which favor the use as engine mount
in submarine and ships where weight is the highest priority.
significant role in wide range of tissue engineering application
such as bone scaffolds since the last decade. The aim
of this article is to provide the comprehensive overview of
biocompatible and biodegradable polymer materials and
composite materials with their advantages and drawbacks
in the application of biomaterial scaffolds, furthermore the
properties and degradation criteria of the biomaterials are
discussed in this review.
finite element approach utilizes the concept of viscoelastic damping, which is carried out by direct integration. This paper describes the potential application of composite material as a damper device because of its damping, high stiffness and low weight properties, which favor the use as engine mount
in submarine and ships where weight is the highest priority.