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ARTICLES-COMPLETE LIST by Syam Prasad P

Mesoporous bioactive glass nanoparticles (MBGNPs) containing therapeutic ions have shown signific... more Mesoporous bioactive glass nanoparticles (MBGNPs) containing therapeutic ions have shown significant promise in the realm of hard and soft tissue repair and regeneration, owing to their multifunctional biological properties. In this study, gallium-incorporated silica-based gallium incorporated MBGNPs (Ga-MBGNPs) with fixed amount of Li 2 O (8 mol %) were synthesized using an emulsion-assisted sol-gel method. The impact of Ga 2 O 3 integration into the silicate glass network was evaluated by investigating the microtextural properties. The results confirmed the production of spherical-shaped, nano-sized, amorphous particles with an enhanced specific surface area and ordered hexagonal meso-porosity (10-20 nm) in the developed Ga-MBGNPs. The in vitro bioactivity, assessed through hydroxyapatite (HAp) layer formation in simulated body fluid (SBF), over varying time intervals (0, 1, 3, 7, 14 & 21 days), revealed pronounced formation of short rod-like carbonated HAp with increasing immersion time and Ga 3+ content in all glasses. However, a delayed apatite formation was observed for compositiondependent Ga-4 and Ga-5 MBGs during the initial incubation periods (1, 3, and 7 days). Further, the presence of Li + ions along with Ga 3+ enhanced the apatite deposition when compared with the only Ga 3+ inclusion. Evaluation of degradation rate and pH values indicated enhanced apatite formation with lower Ga ion content, while a slight reduction was noted with higher Ga ion content, attributable to the presence of reactive Si-O-Si bonds. Furthermore, analysis using a Zeta potential analyzer confirmed the dispersibility and bioreactivity of all glass powders owing to their higher negative surface charge. Moreover, Ga-MBGNPs exhibited notable antimicrobial effects against both E. coli and S. aureus bacteria due to the release of Ga 3+ ions. Overall, the findings suggest that the incorporation of Ga in MBGNPs renders them potential multifunctional candidates for expediting the healing of bone tissue injuries in biomedical applications.

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for... more Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO-22Na 2 O-(24 − x)CaO-46P 2 O 5-xZrO 2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 • C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (T g), crystallization temperature (T c), and melting temperature (T m), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that the glass-forming ability and thermal stability of glasses increased with the increase in zirconia mol%. The XRD, FTIR, and SEM-EDS data confirmed a thin hydroxyapatite (HAp) layer over the sample surface after incubation in SBF for 1 and 5 days. Furthermore, the development of layer found to be increased with the increase of incubation time. The degradation of the glasses in SBF increased with incubation time and decreased gradually with the increase content of ZrO 2 mol% in the host glass matrix. A sudden rise in initial pH values of residual SBF for 1 day owing to ion leaching and increase of Ca 2+ and PO 4 3− ions and then decreased. These findings confirmed the suitability of choosing material for bone-related applications.

ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O ... more ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O 5 (where X = 2, 4, 6, 8, 10 mol%) were developed by melt-quenching process. The physical, thermal and other structural properties of the glasses were studied in detail. By employing various characterization techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) in addition to the energy dispersion spectroscopy (EDS), and Raman spectroscopy, the structural properties were analyzed. Interestingly, physical, thermal and mechanical properties were enhanced with the increasing content of zinc oxide up to 8 mol%, due to the presence of more ionic nature of P-O-Zn bonds than P-O-P bonds in the glass network. The FTIR and Raman analysis revealed the evolution of the phosphate network with increasing zinc concentration and leads to progressive depolymerisation of the glass network. The obtained results from the physical and structural properties of these zinc added calcium phosphate glasses support their potential to use as bone implant applications.

ORIGINAL ARTICLES 2020 by Syam Prasad P

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for... more Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO-22Na 2 O-(24 − x)CaO-46P 2 O 5-xZrO 2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 • C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (T g), crystallization temperature (T c), and melting temperature (T m), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that the glass-forming ability and thermal stability of glasses increased with the increase in zirconia mol%. The XRD, FTIR, and SEM-EDS data confirmed a thin hydroxyapatite (HAp) layer over the sample surface after incubation in SBF for 1 and 5 days. Furthermore, the development of layer found to be increased with the increase of incubation time. The degradation of the glasses in SBF increased with incubation time and decreased gradually with the increase content of ZrO 2 mol% in the host glass matrix. A sudden rise in initial pH values of residual SBF for 1 day owing to ion leaching and increase of Ca 2+ and PO 4 3− ions and then decreased. These findings confirmed the suitability of choosing material for bone-related applications.

Papers by Syam Prasad P

Solid State Communications, 2004

PbO–B 2 O 3 glasses containing different concentrations of MoO 3 ranging from 0 to 4 mol% were pr... more PbO–B 2 O 3 glasses containing different concentrations of MoO 3 ranging from 0 to 4 mol% were prepared. The dielectric properties (constant ′, loss tan δ, ac conductivity σ ac over a range of frequency and temperature and breakdown strength) of these glasses have been ...

INTRODUCTION During recent years, there has been a great deal of interest in preparing and invest... more INTRODUCTION During recent years, there has been a great deal of interest in preparing and investigation of the structure of heavy metal oxide Bi 2 O 3-B 2 O 3 glasses due to high refractive index, high IR transparency and high third order not-linear optical susceptibility [1, 2]. These qualities attribute Bi 2 O 3-B 2 O 3 glasses have found prospective applications in optical and devices in optoelectronics such as ultrafast switches, infrared windows, optical isolators and waveguides in the infrared region [3-5]. But, heavy metal oxides like Bi 2 O 3 unable to form

Physicoelectrical properties like density, dielectric properties, optical absorption and infrared... more Physicoelectrical properties like density, dielectric properties, optical absorption and infrared absorption data are presented for borophosphate glasses doped with nickel ions. Standard samples of ZnO-B 2 O 3-P 2 O 5 glass system were prepared by the melt quenching technique in the compositional series containing 0.2, 0.4, 0.6, 0.8, and 1.0 mol % of nickel. The dc conductivity for these samples measured in the temperature range 473−623 K. The analysis of dc conductivity, electrical conductivity is affected by the structural change. The electronic conduction seems to be dominant in the higher concentration range. From the optical absorption and IR spectral studies, nickel ions prefer to occupy both tetrahedral and octahedral positions in the glass network; compare to tetrahedral, octahedral positions seems to dominate when the concentration of NiO is raised above 0.6 mol% in the glass matrix.

Journal of Alloys and Compounds, Nov 1, 2021

Abstract Borate incorporated novel germanium based glass system was fabricated by traditional mel... more Abstract Borate incorporated novel germanium based glass system was fabricated by traditional melt-quenching technique and is used as a probe for the generation of efficient lasers. In this context, we have explored in detail the impact of B2O3 addition on optical properties of GeSbNa (germanate-antimono-sodium) glass composition. The optical absorption spectra reveal that the cut-off edge of the glasses is shifted to lower wavelengths, due to smaller number of (NBO’s) non-bridging oxygen atoms. Using optical energy band gap values, the phonon energy (EΩ) of the glass system was calculated. Extinction coefficient (k) values were found to decrease in the wavelength range of 290-335 nm which is used for low loss optical devices. The refractive index (RI) of the glasses decreased, indicating that the entire B2O3 doped GeSbNa glass system obeys the normal dispersion mechanism. In addition, the boron mixed GeSbNa glass system shows low phonon energy, making it ideal for rare earth ion hosting glass systems for laser rods and promising candidate for manufacturing optical fibers.

Journal of materials research and technology, Jul 1, 2022

Ceramics International, 2018

The up-conversion emission of Nd 3+ , Sm 3+ and Er 3+ has been studied in a new halogenoantimonit... more The up-conversion emission of Nd 3+ , Sm 3+ and Er 3+ has been studied in a new halogenoantimonite glass with the chemical composition 80 Sb 2 O 3-10 ZnBr 2-10 KCl. Doping concentration was 0.2 mol% of lanthanide (Ln) ions. Rare earths were introduced as fluorides LnF 3 that were further converted into oxides. Main physical properties of base glass were measured, including density, thermal expansion, characteristic temperatures, refractive index and optical transmission. The amount of residual hydroxyls was calculated from the OH absorption band around 3000 nm. The recorded up-conversion emission lines are λ em = 536 nm for Nd 3+ pumped at 805 nm; λ em = 563 nm, 600 nm, 631 nm and 645 nm for Sm 3+ pumped at 945 nm; λ em = 531 nm for Er 3+ pumped at 798 nm. Co-doped glass (0.1 Yb 3+ + 0.1 Er 3+) pumped at 980 nm has three emission lines at 524 nm, 545 nm and 650 nm. Corresponding transitions have been identified and the mechanisms ruling the up-conversion process is discussed. They include excited state absorption (ESA), energy transfer (ET) cooperative energy transfer (CET), emission assisted by phonon (EAP), multiphonon relaxation (MR) and cross-relaxation (CR).

Karbala International Journal of Modern Science, 2015

Physical and spectral properties like density, optical absorption, infrared and ESR spectral stud... more Physical and spectral properties like density, optical absorption, infrared and ESR spectral studies are measured for lead fluorophosphate glasses doped with molybdenum ions. The melt quenching technique was used for the preparation of standard samples of PbOeZnF 2 eP 2 O 5 glass system in the compositional series containing 0.1, 0.2, 0.3, 0.4, 0.8 and 1.0 mol% of molybdenum. Spectroscopic studies, ESR, optical absorption and IR reveal the presence of molybdenum ions with the MoO 4 and MoO 6 structural groups in these glasses. The oxidation state of molybdenum are mostly existing in Mo 5þ up to 0.2 mol% beyond that concentration exist in Mo 6þ state.

Journal of composites science, Sep 4, 2020

ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O ... more ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O 5 (where X = 2, 4, 6, 8, 10 mol%) were developed by melt-quenching process. The physical, thermal and other structural properties of the glasses were studied in detail. By employing various characterization techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) in addition to the energy dispersion spectroscopy (EDS), and Raman spectroscopy, the structural properties were analyzed. Interestingly, physical, thermal and mechanical properties were enhanced with the increasing content of zinc oxide up to 8 mol%, due to the presence of more ionic nature of P-O-Zn bonds than P-O-P bonds in the glass network. The FTIR and Raman analysis revealed the evolution of the phosphate network with increasing zinc concentration and leads to progressive depolymerisation of the glass network. The obtained results from the physical and structural properties of these zinc added calcium phosphate glasses support their potential to use as bone implant applications.

Ceramics International, 2017

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Journal of materials research and technology, Nov 1, 2021

Journal of Composites Science, 2020

ZnO incorporated phosphate based bioglasses with the composition xZnO–22Na2O–24CaO–(54-X)P2O5 (wh... more ZnO incorporated phosphate based bioglasses with the composition xZnO–22Na2O–24CaO–(54-X)P2O5 (where X = 2, 4, 6, 8, 10 mol%) were developed by melt-quenching process. The physical, thermal and other structural properties of the glasses were studied in detail. By employing various characterization techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) in addition to the energy dispersion spectroscopy (EDS), and Raman spectroscopy, the structural properties were analyzed. Interestingly, physical, thermal and mechanical properties were enhanced with the increasing content of zinc oxide up to 8 mol%, due to the presence of more ionic nature of P–O–Zn bonds than P–O–P bonds in the glass network. The FTIR and Raman analysis revealed the evolution of the phosphate network with increasing zinc concentration and leads to progressive depolymerisation of the glass network. The obtained results from the physical and...

Physical Chemistry, 2013

The paper deals with the spectroscopic properties of Li 2 O-ZnO-B 2 O 3 glass containing differen... more The paper deals with the spectroscopic properties of Li 2 O-ZnO-B 2 O 3 glass containing different concentrations of MoO 3 (ranging from 1 to 5 mol %) were prepared by melt quenching. Spectroscopic (infrared, optical absorption spectra and ESR) properties of these glasses have been carried out. The Optical absorption Spectrum contains one broad absorption band at 681 nm, this attributed to the excitation of Mo 5+ (4d 1) ion. ESR studies reveal Molybdenum ions are expected to exist mainly in the Mo 6+ state in the glass network. As the concentration of MoO 3 is increased, especially beyond 5.0 mol %, the colour of the glasses increased, that indicating the reduction of molybdenum ions from the Mo 6+ state to the Mo 5+ state. ESR, IR and Optical absorption spectra of paramagnetic ion in the above glasses reveal that the site symmetry of the transition metal ion is elongated octahedral.

Health care technology is in use for a decade or more in India. The use of technology in healthca... more Health care technology is in use for a decade or more in India. The use of technology in healthcare especially in public health is very common due to the recent development in Information Communication Technology. The costs of equipments in ICT are generally falling. The present paper is looking at various studies on Telehealth technology. Based on the data available on the utilization it also tries to explain the utilization pattern. The utilization of such systems depends on various factors. They include, costs of setting up and maintaining such systems, the availability of man power, e-readiness, availability of equipments, cost of access, enabling regulatory environment, sustainability of such systems and so on. The Telemedicine user meet held in May 2007 at Ahmedabad, India, there were 30612 super specialty consultations since the inception. As per the data available, there are 563 super-specialty consultations per month in 10 centres in India.

Materials, 2020

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for... more Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO–22Na2O–(24 − x)CaO–46P2O5–xZrO2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 °C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that ...

Mesoporous bioactive glass nanoparticles (MBGNPs) containing therapeutic ions have shown signific... more Mesoporous bioactive glass nanoparticles (MBGNPs) containing therapeutic ions have shown significant promise in the realm of hard and soft tissue repair and regeneration, owing to their multifunctional biological properties. In this study, gallium-incorporated silica-based gallium incorporated MBGNPs (Ga-MBGNPs) with fixed amount of Li 2 O (8 mol %) were synthesized using an emulsion-assisted sol-gel method. The impact of Ga 2 O 3 integration into the silicate glass network was evaluated by investigating the microtextural properties. The results confirmed the production of spherical-shaped, nano-sized, amorphous particles with an enhanced specific surface area and ordered hexagonal meso-porosity (10-20 nm) in the developed Ga-MBGNPs. The in vitro bioactivity, assessed through hydroxyapatite (HAp) layer formation in simulated body fluid (SBF), over varying time intervals (0, 1, 3, 7, 14 & 21 days), revealed pronounced formation of short rod-like carbonated HAp with increasing immersion time and Ga 3+ content in all glasses. However, a delayed apatite formation was observed for compositiondependent Ga-4 and Ga-5 MBGs during the initial incubation periods (1, 3, and 7 days). Further, the presence of Li + ions along with Ga 3+ enhanced the apatite deposition when compared with the only Ga 3+ inclusion. Evaluation of degradation rate and pH values indicated enhanced apatite formation with lower Ga ion content, while a slight reduction was noted with higher Ga ion content, attributable to the presence of reactive Si-O-Si bonds. Furthermore, analysis using a Zeta potential analyzer confirmed the dispersibility and bioreactivity of all glass powders owing to their higher negative surface charge. Moreover, Ga-MBGNPs exhibited notable antimicrobial effects against both E. coli and S. aureus bacteria due to the release of Ga 3+ ions. Overall, the findings suggest that the incorporation of Ga in MBGNPs renders them potential multifunctional candidates for expediting the healing of bone tissue injuries in biomedical applications.

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for... more Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO-22Na 2 O-(24 − x)CaO-46P 2 O 5-xZrO 2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 • C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (T g), crystallization temperature (T c), and melting temperature (T m), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that the glass-forming ability and thermal stability of glasses increased with the increase in zirconia mol%. The XRD, FTIR, and SEM-EDS data confirmed a thin hydroxyapatite (HAp) layer over the sample surface after incubation in SBF for 1 and 5 days. Furthermore, the development of layer found to be increased with the increase of incubation time. The degradation of the glasses in SBF increased with incubation time and decreased gradually with the increase content of ZrO 2 mol% in the host glass matrix. A sudden rise in initial pH values of residual SBF for 1 day owing to ion leaching and increase of Ca 2+ and PO 4 3− ions and then decreased. These findings confirmed the suitability of choosing material for bone-related applications.

ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O ... more ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O 5 (where X = 2, 4, 6, 8, 10 mol%) were developed by melt-quenching process. The physical, thermal and other structural properties of the glasses were studied in detail. By employing various characterization techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) in addition to the energy dispersion spectroscopy (EDS), and Raman spectroscopy, the structural properties were analyzed. Interestingly, physical, thermal and mechanical properties were enhanced with the increasing content of zinc oxide up to 8 mol%, due to the presence of more ionic nature of P-O-Zn bonds than P-O-P bonds in the glass network. The FTIR and Raman analysis revealed the evolution of the phosphate network with increasing zinc concentration and leads to progressive depolymerisation of the glass network. The obtained results from the physical and structural properties of these zinc added calcium phosphate glasses support their potential to use as bone implant applications.

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for... more Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO-22Na 2 O-(24 − x)CaO-46P 2 O 5-xZrO 2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 • C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (T g), crystallization temperature (T c), and melting temperature (T m), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that the glass-forming ability and thermal stability of glasses increased with the increase in zirconia mol%. The XRD, FTIR, and SEM-EDS data confirmed a thin hydroxyapatite (HAp) layer over the sample surface after incubation in SBF for 1 and 5 days. Furthermore, the development of layer found to be increased with the increase of incubation time. The degradation of the glasses in SBF increased with incubation time and decreased gradually with the increase content of ZrO 2 mol% in the host glass matrix. A sudden rise in initial pH values of residual SBF for 1 day owing to ion leaching and increase of Ca 2+ and PO 4 3− ions and then decreased. These findings confirmed the suitability of choosing material for bone-related applications.

Solid State Communications, 2004

PbO–B 2 O 3 glasses containing different concentrations of MoO 3 ranging from 0 to 4 mol% were pr... more PbO–B 2 O 3 glasses containing different concentrations of MoO 3 ranging from 0 to 4 mol% were prepared. The dielectric properties (constant ′, loss tan δ, ac conductivity σ ac over a range of frequency and temperature and breakdown strength) of these glasses have been ...

INTRODUCTION During recent years, there has been a great deal of interest in preparing and invest... more INTRODUCTION During recent years, there has been a great deal of interest in preparing and investigation of the structure of heavy metal oxide Bi 2 O 3-B 2 O 3 glasses due to high refractive index, high IR transparency and high third order not-linear optical susceptibility [1, 2]. These qualities attribute Bi 2 O 3-B 2 O 3 glasses have found prospective applications in optical and devices in optoelectronics such as ultrafast switches, infrared windows, optical isolators and waveguides in the infrared region [3-5]. But, heavy metal oxides like Bi 2 O 3 unable to form

Physicoelectrical properties like density, dielectric properties, optical absorption and infrared... more Physicoelectrical properties like density, dielectric properties, optical absorption and infrared absorption data are presented for borophosphate glasses doped with nickel ions. Standard samples of ZnO-B 2 O 3-P 2 O 5 glass system were prepared by the melt quenching technique in the compositional series containing 0.2, 0.4, 0.6, 0.8, and 1.0 mol % of nickel. The dc conductivity for these samples measured in the temperature range 473−623 K. The analysis of dc conductivity, electrical conductivity is affected by the structural change. The electronic conduction seems to be dominant in the higher concentration range. From the optical absorption and IR spectral studies, nickel ions prefer to occupy both tetrahedral and octahedral positions in the glass network; compare to tetrahedral, octahedral positions seems to dominate when the concentration of NiO is raised above 0.6 mol% in the glass matrix.

Journal of Alloys and Compounds, Nov 1, 2021

Abstract Borate incorporated novel germanium based glass system was fabricated by traditional mel... more Abstract Borate incorporated novel germanium based glass system was fabricated by traditional melt-quenching technique and is used as a probe for the generation of efficient lasers. In this context, we have explored in detail the impact of B2O3 addition on optical properties of GeSbNa (germanate-antimono-sodium) glass composition. The optical absorption spectra reveal that the cut-off edge of the glasses is shifted to lower wavelengths, due to smaller number of (NBO’s) non-bridging oxygen atoms. Using optical energy band gap values, the phonon energy (EΩ) of the glass system was calculated. Extinction coefficient (k) values were found to decrease in the wavelength range of 290-335 nm which is used for low loss optical devices. The refractive index (RI) of the glasses decreased, indicating that the entire B2O3 doped GeSbNa glass system obeys the normal dispersion mechanism. In addition, the boron mixed GeSbNa glass system shows low phonon energy, making it ideal for rare earth ion hosting glass systems for laser rods and promising candidate for manufacturing optical fibers.

Journal of materials research and technology, Jul 1, 2022

Ceramics International, 2018

The up-conversion emission of Nd 3+ , Sm 3+ and Er 3+ has been studied in a new halogenoantimonit... more The up-conversion emission of Nd 3+ , Sm 3+ and Er 3+ has been studied in a new halogenoantimonite glass with the chemical composition 80 Sb 2 O 3-10 ZnBr 2-10 KCl. Doping concentration was 0.2 mol% of lanthanide (Ln) ions. Rare earths were introduced as fluorides LnF 3 that were further converted into oxides. Main physical properties of base glass were measured, including density, thermal expansion, characteristic temperatures, refractive index and optical transmission. The amount of residual hydroxyls was calculated from the OH absorption band around 3000 nm. The recorded up-conversion emission lines are λ em = 536 nm for Nd 3+ pumped at 805 nm; λ em = 563 nm, 600 nm, 631 nm and 645 nm for Sm 3+ pumped at 945 nm; λ em = 531 nm for Er 3+ pumped at 798 nm. Co-doped glass (0.1 Yb 3+ + 0.1 Er 3+) pumped at 980 nm has three emission lines at 524 nm, 545 nm and 650 nm. Corresponding transitions have been identified and the mechanisms ruling the up-conversion process is discussed. They include excited state absorption (ESA), energy transfer (ET) cooperative energy transfer (CET), emission assisted by phonon (EAP), multiphonon relaxation (MR) and cross-relaxation (CR).

Karbala International Journal of Modern Science, 2015

Physical and spectral properties like density, optical absorption, infrared and ESR spectral stud... more Physical and spectral properties like density, optical absorption, infrared and ESR spectral studies are measured for lead fluorophosphate glasses doped with molybdenum ions. The melt quenching technique was used for the preparation of standard samples of PbOeZnF 2 eP 2 O 5 glass system in the compositional series containing 0.1, 0.2, 0.3, 0.4, 0.8 and 1.0 mol% of molybdenum. Spectroscopic studies, ESR, optical absorption and IR reveal the presence of molybdenum ions with the MoO 4 and MoO 6 structural groups in these glasses. The oxidation state of molybdenum are mostly existing in Mo 5þ up to 0.2 mol% beyond that concentration exist in Mo 6þ state.

Journal of composites science, Sep 4, 2020

ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O ... more ZnO incorporated phosphate based bioglasses with the composition xZnO-22Na 2 O-24CaO-(54-X)P 2 O 5 (where X = 2, 4, 6, 8, 10 mol%) were developed by melt-quenching process. The physical, thermal and other structural properties of the glasses were studied in detail. By employing various characterization techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) in addition to the energy dispersion spectroscopy (EDS), and Raman spectroscopy, the structural properties were analyzed. Interestingly, physical, thermal and mechanical properties were enhanced with the increasing content of zinc oxide up to 8 mol%, due to the presence of more ionic nature of P-O-Zn bonds than P-O-P bonds in the glass network. The FTIR and Raman analysis revealed the evolution of the phosphate network with increasing zinc concentration and leads to progressive depolymerisation of the glass network. The obtained results from the physical and structural properties of these zinc added calcium phosphate glasses support their potential to use as bone implant applications.

Ceramics International, 2017

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Journal of materials research and technology, Nov 1, 2021

Journal of Composites Science, 2020

ZnO incorporated phosphate based bioglasses with the composition xZnO–22Na2O–24CaO–(54-X)P2O5 (wh... more ZnO incorporated phosphate based bioglasses with the composition xZnO–22Na2O–24CaO–(54-X)P2O5 (where X = 2, 4, 6, 8, 10 mol%) were developed by melt-quenching process. The physical, thermal and other structural properties of the glasses were studied in detail. By employing various characterization techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) in addition to the energy dispersion spectroscopy (EDS), and Raman spectroscopy, the structural properties were analyzed. Interestingly, physical, thermal and mechanical properties were enhanced with the increasing content of zinc oxide up to 8 mol%, due to the presence of more ionic nature of P–O–Zn bonds than P–O–P bonds in the glass network. The FTIR and Raman analysis revealed the evolution of the phosphate network with increasing zinc concentration and leads to progressive depolymerisation of the glass network. The obtained results from the physical and...

Physical Chemistry, 2013

The paper deals with the spectroscopic properties of Li 2 O-ZnO-B 2 O 3 glass containing differen... more The paper deals with the spectroscopic properties of Li 2 O-ZnO-B 2 O 3 glass containing different concentrations of MoO 3 (ranging from 1 to 5 mol %) were prepared by melt quenching. Spectroscopic (infrared, optical absorption spectra and ESR) properties of these glasses have been carried out. The Optical absorption Spectrum contains one broad absorption band at 681 nm, this attributed to the excitation of Mo 5+ (4d 1) ion. ESR studies reveal Molybdenum ions are expected to exist mainly in the Mo 6+ state in the glass network. As the concentration of MoO 3 is increased, especially beyond 5.0 mol %, the colour of the glasses increased, that indicating the reduction of molybdenum ions from the Mo 6+ state to the Mo 5+ state. ESR, IR and Optical absorption spectra of paramagnetic ion in the above glasses reveal that the site symmetry of the transition metal ion is elongated octahedral.

Health care technology is in use for a decade or more in India. The use of technology in healthca... more Health care technology is in use for a decade or more in India. The use of technology in healthcare especially in public health is very common due to the recent development in Information Communication Technology. The costs of equipments in ICT are generally falling. The present paper is looking at various studies on Telehealth technology. Based on the data available on the utilization it also tries to explain the utilization pattern. The utilization of such systems depends on various factors. They include, costs of setting up and maintaining such systems, the availability of man power, e-readiness, availability of equipments, cost of access, enabling regulatory environment, sustainability of such systems and so on. The Telemedicine user meet held in May 2007 at Ahmedabad, India, there were 30612 super specialty consultations since the inception. As per the data available, there are 563 super-specialty consultations per month in 10 centres in India.

Materials, 2020

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for... more Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO–22Na2O–(24 − x)CaO–46P2O5–xZrO2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 °C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that ...

Purpose of Review Dental caries or tooth decay is one of the communal problems in the world which... more Purpose of Review Dental caries or tooth decay is one of the communal problems in the world which can affect not only the oral health but also the general health conditions. The main objective of this systematic review is to explore the efficacy of bioactive glass-based toothpastes against cariogenic bacteria. Recent Findings Bioactive glass particulates containing toothpaste show better remineralization potential on demineralized enamel and dentin when compared with toothpaste containing various bioactive constituents such as fluoride and potassium chloride. These constituents in conventional toothpaste can rapidly streak off due to acidic impact in the oral environment as the bioactive glass provides minerals for demineralized enamel and dentin by forming a strong hydroxyapatite (HAp) layer on its surface. Further, the therapeutic ions present in the bioglass can resist plaque formation by raising the pH of the surrounding environment or saliva and create amicable media for healthier teeth. Summary Toothpaste containing bioactive glass particles undoubtedly displayed the remineralizing potentiality of the dental hard tissues. Dynamics of the mineralization through different bioactive glass materials needs further investigations. In order to prevent dental cavities and improve oral health, it is important to identify and study different effective bioglass particles in toothpaste.