I work as a physicist and health-physicist 25 years of experience in assessment of absorbed dose and dosimetry for health purposes of personnel, who work with ionizing radiation. Moreover, environmental monitoring is doing by Gamma spectroscopy and Thermoluminescence dosimetry. I've been actively engaged in and managed several scientific projects and also routine monitoring programs.Having worked in internationally oriented scientific environments for five years (University Putra Malaysia, 2010-2014), through my Ph.D., where I obtained my Ideal related to synthesis nanophosphor as an ionizing radiation sensor for improving monitoring of individual. I am very well capable of working with a wide range of synthesis, characterization of nanomaterials such as XRD, TEM, FTIR, UV-VIS, TGA, DTA, particularly TLD characterization of Thermoluminescence Dosimeters. Furthermore, working with different software, such as
This study details an innovative single-step thermal synthesis of nano-sized lithium tetraborate ... more This study details an innovative single-step thermal synthesis of nano-sized lithium tetraborate doped with 0.1 %wt copper and its characterization. The heating temperature for the synthesis of the nanoparticle material was optimized by variation between 200 and 850 °C. The optimum amount of polyvinyl pyrrolidone (PVP) the capping agent was determined to be 0.027 mol per 1 g LTB-Cu. The calcination time was 2 h. Characterization of the samples was carried out using Thermogravimetry Analysis (TGA), Derivative Thermogravimetry (DTG), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared (FTIR) Spectroscopy, X-ray diffractometer (XRD), transmission electron microscopy (TEM) and Ultraviolet–Visible (UV–Vis) spectroscopy. The product was thermally stable above 450 °C. FTIR, XRD and TEM results confirmed the formation of pure nano-crystalline copper doped lithium tetraborate between 450 and 750 °C. The optical bandgap was estimated to be 5.02–6.05 eV in the presence of different amounts of PVP at various calcination temperatures.
Introduction: The basic features of nanophosphors specified by their structural state are propoun... more Introduction: The basic features of nanophosphors specified by their structural state are propounded. New era in determination of absorbed dose is emphasized by using nanophosphor Lithium Tetraborate dosimeters. Objective: They can be used for measuring absorbed dose of ionizing radiations more efficient than known micro-scaled materials in medical, personal and environmental dosimetry. Methodology: Lithium carbonate reagent and boric acid were used as precursors. Poly vinyl pyrrolidone (PVP) was used as a capping agent to reduce the agglomeration of the particles. Besides, nitrate of copper (II) were used as dopants. Deionized water was used as the solvent. All materials which, utilized without any further purification, were purchased from Sigma Aldrich Company (United Kingdom) with purities more than 99.8% and used without further purification. Results and Discussion: The effect of a high concentration of surface trapping centers and grain size of particles on the nanophosphor lum...
Michael Hoch, K Nair American Ceramic Society Bulletin 58:22, 191-93, 1979. ... The J prime struc... more Michael Hoch, K Nair American Ceramic Society Bulletin 58:22, 191-93, 1979. ... The J prime structure is richer in O sub 2 than Beta prime is; its proposed composition is Si sub 2 Al sub 3 O sub 3 + 1.5x N sub 5 minus x (0 less than x less than 4). Refractories(WC).
Nickel ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and ... more Nickel ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and various concentrations of poly(vinylpyrrolidone) followed by calcination temperature. X-ray diffraction (XRD) analysis was performed to determine the degree of crystallinity of the ferrite nanoparticles. By transmission electron microscopy, the morphology and average particle size of the nickel ferrite nanoparticles were evaluated which had good agreement with the XRD results. Fourier transform infrared spectroscopy suggested the presence of metal oxide bands in all samples as well as the effective elimination of organic constituents after calcinations. Measurements of the extent of magnetization of the nickel ferrite nanoparticles synthesized in different concentrations were obtained at room temperature using a vibrating sample magnetometer.
Tissue equivalent thermoluminescence dosimeters (TLDs) are commonly used for monitoring dose of i... more Tissue equivalent thermoluminescence dosimeters (TLDs) are commonly used for monitoring dose of ionizing radiation as personal or medical radiation dosimeters. The commercially available macro-scale lithium tetra borates (LTB) have several drawbacks such as poor Thermoluminescent (TL) intensity, limited dose linearity, losses information with time (fading) and energy dependence, which might be improved by using nano-scale activated LTB, the main goal of this study. LTB is the most popular material for radiation dosimetry because of its effective atomic number (Zeff = 7.4) that close with the Zeff of human tissue (7.42). Furthermore, LTB is almost stable chemical compound and can be easily doped with TL sensitizers. In line with this development the objectives of this work were to synthesize and to investigate the structural characteristics and TL properties of undoped LTB and silver and copper doped LTB (LTB-Ag and LTB-Cu) nanoparticles for dosimetric applications. The LTB nanoparti...
Undoped lithium tetraborate nanophosphor with tetragonal crystal structure and average size of ~3... more Undoped lithium tetraborate nanophosphor with tetragonal crystal structure and average size of ~3.3 nm was synthesized by an innovative single step thermal treatment method for the first time. The synthesized nanophosphors showed excellent thermoluminescence properties and enough potential for personal and medical dosimetry. The thermoluminescence properties of nanocrystalline chips were studied at room temperature after exposure to gamma irradiation using 60Co sources. The dosimetric peak of prepared ultrafine nanophosphors showed a linear response over a wide range of doses from 10-1 to 0.15×103 Gy. Moreover, the samples illustrate non energy dependence among a wide range energy interval from 24 keV up to 1250 keV and almost no fading during one month storage.
This study includes the synthesis of nano-sized lithium tetraborate by an innovative single step ... more This study includes the synthesis of nano-sized lithium tetraborate by an innovative single step thermal treatment method and characterization of the products. The heating temperature for the synthesis was varied between 200 and 850 ◦C with the retention time of 2 h. Polyvinyl pyrrolidone (PVP) with different concentrations was used as surfactant. Characterization of the samples was achieved by Thermogravimetric Analysis (TGA), Derivative Thermogravimetry Analysis (DTA), Differential Scanning Calorimetry (DSC), Fourier transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) techniques and UV-Visible spectroscopy. Thermal analysis of initial solution allowed the optimization of the heat treatment program and showed that the thermal stability of samples is started at 460 ◦C. FTIR, XRD and TEM results proved the formation of pure nano-crystalline lithium tetraborate at temperature between 460 and 750 ◦C. Furthermore, the bandgap investigation was performed using UV-Visible spectra in presence of different concentrations of PVP and in variety of calcination temperatures. The estimated optical bandgap was found to be between 5.2 and 6.2 eV.
This study details an innovative single-step thermal synthesis of nano-sized lithium tetraborate ... more This study details an innovative single-step thermal synthesis of nano-sized lithium tetraborate doped with 0.1 %wt copper and its characterization. The heating temperature for the synthesis of the nanoparticle material was optimized by variation between 200 and 850 °C. The optimum amount of polyvinyl pyrrolidone (PVP) the capping agent was determined to be 0.027 mol per 1 g LTB-Cu. The calcination time was 2 h. Characterization of the samples was carried out using Thermogravimetry Analysis (TGA), Derivative Thermogravimetry (DTG), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared (FTIR) Spectroscopy, X-ray diffractometer (XRD), transmission electron microscopy (TEM) and Ultraviolet–Visible (UV–Vis) spectroscopy. The product was thermally stable above 450 °C. FTIR, XRD and TEM results confirmed the formation of pure nano-crystalline copper doped lithium tetraborate between 450 and 750 °C. The optical bandgap was estimated to be 5.02–6.05 eV in the presence of different amounts of PVP at various calcination temperatures.
Introduction: The basic features of nanophosphors specified by their structural state are propoun... more Introduction: The basic features of nanophosphors specified by their structural state are propounded. New era in determination of absorbed dose is emphasized by using nanophosphor Lithium Tetraborate dosimeters. Objective: They can be used for measuring absorbed dose of ionizing radiations more efficient than known micro-scaled materials in medical, personal and environmental dosimetry. Methodology: Lithium carbonate reagent and boric acid were used as precursors. Poly vinyl pyrrolidone (PVP) was used as a capping agent to reduce the agglomeration of the particles. Besides, nitrate of copper (II) were used as dopants. Deionized water was used as the solvent. All materials which, utilized without any further purification, were purchased from Sigma Aldrich Company (United Kingdom) with purities more than 99.8% and used without further purification. Results and Discussion: The effect of a high concentration of surface trapping centers and grain size of particles on the nanophosphor lum...
Michael Hoch, K Nair American Ceramic Society Bulletin 58:22, 191-93, 1979. ... The J prime struc... more Michael Hoch, K Nair American Ceramic Society Bulletin 58:22, 191-93, 1979. ... The J prime structure is richer in O sub 2 than Beta prime is; its proposed composition is Si sub 2 Al sub 3 O sub 3 + 1.5x N sub 5 minus x (0 less than x less than 4). Refractories(WC).
Nickel ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and ... more Nickel ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and various concentrations of poly(vinylpyrrolidone) followed by calcination temperature. X-ray diffraction (XRD) analysis was performed to determine the degree of crystallinity of the ferrite nanoparticles. By transmission electron microscopy, the morphology and average particle size of the nickel ferrite nanoparticles were evaluated which had good agreement with the XRD results. Fourier transform infrared spectroscopy suggested the presence of metal oxide bands in all samples as well as the effective elimination of organic constituents after calcinations. Measurements of the extent of magnetization of the nickel ferrite nanoparticles synthesized in different concentrations were obtained at room temperature using a vibrating sample magnetometer.
Tissue equivalent thermoluminescence dosimeters (TLDs) are commonly used for monitoring dose of i... more Tissue equivalent thermoluminescence dosimeters (TLDs) are commonly used for monitoring dose of ionizing radiation as personal or medical radiation dosimeters. The commercially available macro-scale lithium tetra borates (LTB) have several drawbacks such as poor Thermoluminescent (TL) intensity, limited dose linearity, losses information with time (fading) and energy dependence, which might be improved by using nano-scale activated LTB, the main goal of this study. LTB is the most popular material for radiation dosimetry because of its effective atomic number (Zeff = 7.4) that close with the Zeff of human tissue (7.42). Furthermore, LTB is almost stable chemical compound and can be easily doped with TL sensitizers. In line with this development the objectives of this work were to synthesize and to investigate the structural characteristics and TL properties of undoped LTB and silver and copper doped LTB (LTB-Ag and LTB-Cu) nanoparticles for dosimetric applications. The LTB nanoparti...
Undoped lithium tetraborate nanophosphor with tetragonal crystal structure and average size of ~3... more Undoped lithium tetraborate nanophosphor with tetragonal crystal structure and average size of ~3.3 nm was synthesized by an innovative single step thermal treatment method for the first time. The synthesized nanophosphors showed excellent thermoluminescence properties and enough potential for personal and medical dosimetry. The thermoluminescence properties of nanocrystalline chips were studied at room temperature after exposure to gamma irradiation using 60Co sources. The dosimetric peak of prepared ultrafine nanophosphors showed a linear response over a wide range of doses from 10-1 to 0.15×103 Gy. Moreover, the samples illustrate non energy dependence among a wide range energy interval from 24 keV up to 1250 keV and almost no fading during one month storage.
This study includes the synthesis of nano-sized lithium tetraborate by an innovative single step ... more This study includes the synthesis of nano-sized lithium tetraborate by an innovative single step thermal treatment method and characterization of the products. The heating temperature for the synthesis was varied between 200 and 850 ◦C with the retention time of 2 h. Polyvinyl pyrrolidone (PVP) with different concentrations was used as surfactant. Characterization of the samples was achieved by Thermogravimetric Analysis (TGA), Derivative Thermogravimetry Analysis (DTA), Differential Scanning Calorimetry (DSC), Fourier transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) techniques and UV-Visible spectroscopy. Thermal analysis of initial solution allowed the optimization of the heat treatment program and showed that the thermal stability of samples is started at 460 ◦C. FTIR, XRD and TEM results proved the formation of pure nano-crystalline lithium tetraborate at temperature between 460 and 750 ◦C. Furthermore, the bandgap investigation was performed using UV-Visible spectra in presence of different concentrations of PVP and in variety of calcination temperatures. The estimated optical bandgap was found to be between 5.2 and 6.2 eV.
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