Daramola Ayobami | CY Cergy Paris Université (original) (raw)
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Papers by Daramola Ayobami
Daramola Ayobami, 2019
Glasses are ubiquitous and have disordered structure and also tend to be out of equilibrium, due ... more Glasses are ubiquitous and have disordered structure and also tend to be out of equilibrium, due to this fact, they show a rich and complex mechanical behavior: avalanches, strain localization of the plastic deformation into thin shear-bands and also glasses during formation and deformation show how glasses depends on it thermal and the mechanical history. This complex mechanical behavior has led to increased in theoretical and numerical research in recent years. This thesis tends to follows the recent studies performed at the atomistic scale level by using a new scale called mesoscale model which has emerged recently which complement the numerous research done with atomistic simulations of model glasses especially in the area of slow strain rate during atomistic simulation. In the spirit of the Ising model for magnetism or cellular automata for granular avalanches, our lattice model rely on the coupling between a local threshold dynamics and an elastic interaction which produces most of the plasticity activity obtained in our result. My work proposes to explore the status of the yielding transition in the framework of lattice mesocopic models of amorphous plasticity and study the quantitative connection between simulations operating at atomistic and mesocopic scales.
Numerical simulation of sets of differential equations governing each of the stages of the experi... more Numerical simulation of sets of differential equations governing each of the stages of the experimental procedure has proved efficient in understanding the phenomena behind the structure of thermal activation characteristics (TACs) of 110°C thermoluminescence (TL) peak of quartz. This work was undertaken to investigate the effect of heating rates of thermal activation on TAC by a way of numerical simulation of existing model. The ‘early activation’ and ‘late activation’ TACs by following the exact experimental procedures of varying heating rates of thermal activation that produced them, has also been numerically observed in this work. This effect increases with heating rate utilized for thermal activation. Rate of recombination of evicted electron from high temperature TL peak with holes during thermal activation was observed to result into (i) increased sensitization with heating rates of thermal activation (ii) straightforward dependent of temperature at glow-peak maximum intensity (Tm) of high temperature TL peak. The impact of electrons loss to recombination during short irradiation was also observed to also shift in upward manner with heating rates of thermal activation. The overall results have been employed to shed more light on pre-dose phenomenon and its applications in dating.
Drafts by Daramola Ayobami
Daramola Ayobami, 2018
Perform density functional theory (DFT) calculations to investigate the temperature dependence of... more Perform density functional theory (DFT) calculations to investigate the temperature dependence of the crystal growth velocity using KERR experiment which allow analysis of dynamics mechanism. More generally, with decreasing cell size in nonvolatile PC-RAM memories in our computers, this mechanism is expected to prevail over new thermodynamic phase , i intend to employ Phase change Material. Hence, i plan to investigate the growth of the interface at different temperatures of the atomic structure to be use. Question= is it impossible to create large memory data for computers with spin fliped just like frustrated spin, i plan to use any ab initio code for phase change material which i believe should be available like Second Generation Car-Parrinello scheme implemented on CP2K suite of programs. the main aim for the project is see how memory data on computers, phone or any electronic material can be increase by flipping spins in form of spin orbit just like we have qubit in quantum information, i believe it can be achieve if the speed of the spins can be control at a particular temperature.
Dara molar Ayobami Daniel, 2018
In this personal study, i want to see the effect of using an ultra-short laser pulse less than 90... more In this personal study, i want to see the effect of using an ultra-short laser pulse less than 90 femtoseconds on the internal Tungsten diselenide electron spin rotation since iot is a very stable semiconductor. This electronic devices which exploit the extra degree of freedom of electron spins. I plan to use abinitio approach result from the publication of Ab initio calculations of ultra-short carrier dynamics in 2D materials: valley depolarization in single-layer WSe2 Alejandro Molina-S´anchez, * , † Davide Sangalli, ‡ Ludger Wirtz, † and Andrea Marini ‡ 2017 to reduce depolarization effect on the semiconductor material to be used which is definitely Tugsten diselenside because of its semiconductor properties, so as a result of spin rotation's contributions to the spin dynamics are taken into account. This makes the method applicable to a far larger set of magnetic materials. We can as well introduce a honeycomb 2D material into this method to create an ultrafast spintronics.
This research has examined the numerical modeling of electrical resistivity data using Lagrangian... more This research has examined the numerical modeling of electrical resistivity data using Lagrangian interpolation. The Lagrangian generated a polynomial of minimum degree that represents/mimic the original trend of the data. The reason behind the formulated lagrangian is to reduces the stress of interpretation and improve the smoothness of the field curve. The art of the modeling involves a range [a,b] R when R is the range covering the entire data. The numerical concept is applied to reflect the real trend of the data collected. The Lagrangian interpolation skill was carried out using the MATlab program, and the curves generated showed a good fit that represent the entire trend in the range [a,b]. In respect of this, three VES locations were used as test, to confirm the efficacy of the Lagrangian. All the locations showed that the Lagrangian is efficient with the error values maintained at 2.5%,5.6% and 6.6% compared with the conventional error maintained at 2.5%, 6.4% and 5.8%. The research however concluded that the lagrangian of minimum degree are intelligent to guest the trend of the whole data when considered as a whole at values [a,b] of the generated polynomial.
The LM–OSL signal of quartz, while measured at room temperature, is dominated by an intermediate,... more The LM–OSL signal of quartz, while measured at room temperature, is dominated by an intermediate, broad and intense OSL component, so that its contribution and general characteristics are derived very accurately. Through a series of dose–response of 12 quartz samples from southern part of Nigeria that undergoes an experiments, in conjunction with curve fitting studies, a component resolved analysis is carried out studying the correlation between this specific component, termed as LM–OSL component and the
110 C TL glow peak in quartz.
The results of the present work are very promising and clearly support the possibility of extrapolating the TL pre-dose methodology to the OSL pre-dose effect using only the LM–OSL component.
Daramola Ayobami, 2019
Glasses are ubiquitous and have disordered structure and also tend to be out of equilibrium, due ... more Glasses are ubiquitous and have disordered structure and also tend to be out of equilibrium, due to this fact, they show a rich and complex mechanical behavior: avalanches, strain localization of the plastic deformation into thin shear-bands and also glasses during formation and deformation show how glasses depends on it thermal and the mechanical history. This complex mechanical behavior has led to increased in theoretical and numerical research in recent years. This thesis tends to follows the recent studies performed at the atomistic scale level by using a new scale called mesoscale model which has emerged recently which complement the numerous research done with atomistic simulations of model glasses especially in the area of slow strain rate during atomistic simulation. In the spirit of the Ising model for magnetism or cellular automata for granular avalanches, our lattice model rely on the coupling between a local threshold dynamics and an elastic interaction which produces most of the plasticity activity obtained in our result. My work proposes to explore the status of the yielding transition in the framework of lattice mesocopic models of amorphous plasticity and study the quantitative connection between simulations operating at atomistic and mesocopic scales.
Numerical simulation of sets of differential equations governing each of the stages of the experi... more Numerical simulation of sets of differential equations governing each of the stages of the experimental procedure has proved efficient in understanding the phenomena behind the structure of thermal activation characteristics (TACs) of 110°C thermoluminescence (TL) peak of quartz. This work was undertaken to investigate the effect of heating rates of thermal activation on TAC by a way of numerical simulation of existing model. The ‘early activation’ and ‘late activation’ TACs by following the exact experimental procedures of varying heating rates of thermal activation that produced them, has also been numerically observed in this work. This effect increases with heating rate utilized for thermal activation. Rate of recombination of evicted electron from high temperature TL peak with holes during thermal activation was observed to result into (i) increased sensitization with heating rates of thermal activation (ii) straightforward dependent of temperature at glow-peak maximum intensity (Tm) of high temperature TL peak. The impact of electrons loss to recombination during short irradiation was also observed to also shift in upward manner with heating rates of thermal activation. The overall results have been employed to shed more light on pre-dose phenomenon and its applications in dating.
Daramola Ayobami, 2018
Perform density functional theory (DFT) calculations to investigate the temperature dependence of... more Perform density functional theory (DFT) calculations to investigate the temperature dependence of the crystal growth velocity using KERR experiment which allow analysis of dynamics mechanism. More generally, with decreasing cell size in nonvolatile PC-RAM memories in our computers, this mechanism is expected to prevail over new thermodynamic phase , i intend to employ Phase change Material. Hence, i plan to investigate the growth of the interface at different temperatures of the atomic structure to be use. Question= is it impossible to create large memory data for computers with spin fliped just like frustrated spin, i plan to use any ab initio code for phase change material which i believe should be available like Second Generation Car-Parrinello scheme implemented on CP2K suite of programs. the main aim for the project is see how memory data on computers, phone or any electronic material can be increase by flipping spins in form of spin orbit just like we have qubit in quantum information, i believe it can be achieve if the speed of the spins can be control at a particular temperature.
Dara molar Ayobami Daniel, 2018
In this personal study, i want to see the effect of using an ultra-short laser pulse less than 90... more In this personal study, i want to see the effect of using an ultra-short laser pulse less than 90 femtoseconds on the internal Tungsten diselenide electron spin rotation since iot is a very stable semiconductor. This electronic devices which exploit the extra degree of freedom of electron spins. I plan to use abinitio approach result from the publication of Ab initio calculations of ultra-short carrier dynamics in 2D materials: valley depolarization in single-layer WSe2 Alejandro Molina-S´anchez, * , † Davide Sangalli, ‡ Ludger Wirtz, † and Andrea Marini ‡ 2017 to reduce depolarization effect on the semiconductor material to be used which is definitely Tugsten diselenside because of its semiconductor properties, so as a result of spin rotation's contributions to the spin dynamics are taken into account. This makes the method applicable to a far larger set of magnetic materials. We can as well introduce a honeycomb 2D material into this method to create an ultrafast spintronics.
This research has examined the numerical modeling of electrical resistivity data using Lagrangian... more This research has examined the numerical modeling of electrical resistivity data using Lagrangian interpolation. The Lagrangian generated a polynomial of minimum degree that represents/mimic the original trend of the data. The reason behind the formulated lagrangian is to reduces the stress of interpretation and improve the smoothness of the field curve. The art of the modeling involves a range [a,b] R when R is the range covering the entire data. The numerical concept is applied to reflect the real trend of the data collected. The Lagrangian interpolation skill was carried out using the MATlab program, and the curves generated showed a good fit that represent the entire trend in the range [a,b]. In respect of this, three VES locations were used as test, to confirm the efficacy of the Lagrangian. All the locations showed that the Lagrangian is efficient with the error values maintained at 2.5%,5.6% and 6.6% compared with the conventional error maintained at 2.5%, 6.4% and 5.8%. The research however concluded that the lagrangian of minimum degree are intelligent to guest the trend of the whole data when considered as a whole at values [a,b] of the generated polynomial.
The LM–OSL signal of quartz, while measured at room temperature, is dominated by an intermediate,... more The LM–OSL signal of quartz, while measured at room temperature, is dominated by an intermediate, broad and intense OSL component, so that its contribution and general characteristics are derived very accurately. Through a series of dose–response of 12 quartz samples from southern part of Nigeria that undergoes an experiments, in conjunction with curve fitting studies, a component resolved analysis is carried out studying the correlation between this specific component, termed as LM–OSL component and the
110 C TL glow peak in quartz.
The results of the present work are very promising and clearly support the possibility of extrapolating the TL pre-dose methodology to the OSL pre-dose effect using only the LM–OSL component.