P Manoravi | Indira Gandhi Centre for Atomic Research (original) (raw)

Papers by P Manoravi

JOURNAL OF INFRARED AND MILLIMETER WAVES, 2009

The physical principle of laser induced breakdown spectroscopy(LIBS) was interpreted.How the pres... more The physical principle of laser induced breakdown spectroscopy(LIBS) was interpreted.How the pressure affects the laser induced plasma was analyzed.A LIBS experimental system for the low pressure condition was setup and the experiments at the different pressures were carried out.The experimental result expresses how the pressure affects the laser induced plasma quantitatively.The feasibility on the application of LIBS to lunar exploration was discussed.

Journal of Analytical Atomic Spectrometry, 2021

Resolving isobaric interference in situ using laser-ionization mass spectrometry (LIMS).

Spectrochimica Acta Part B: Atomic Spectroscopy, 2022

Materials Today: Proceedings, 2019

International Journal of Mass Spectrometry, 2015

Abstract Nd-YAG laser pulses of 1064, 532, 266 nm in wavelength and of 8 ns and 100 ps in pulse w... more Abstract Nd-YAG laser pulses of 1064, 532, 266 nm in wavelength and of 8 ns and 100 ps in pulse width as well as KrF excimer laser pulses (248 nm) of 30 ns pulse width were employed to deposit thin films of the simulated spent nuclear fuel pellets. The deposited thin films were dissolved in nitric acid and analyzed for residual heavy element (U) to burn-up monitor (Nd) ratio using isotopic dilution mass spectrometry (employing the TIMS technique) to determine the burn-up in these simulated fuel pellets. While the use of ns-laser pulses of 1064 nm wavelength resulted in high elemental fractionation with enhanced Nd concentration compared to the target composition, the 266 nm ps-laser pulses produce films with least elemental fractionation in the film and hence is best suited for this analytical application. Due to the very small amount of material in the deposited film and the amenability of pulsed laser deposition system for use in radioactive shielded hot cells, this analytical technique is suitable for sampling highly radioactive materials.

Vapor pressure data at ultrahigh temperatures (5000 K) are required for refractory materials, esp... more Vapor pressure data at ultrahigh temperatures (5000 K) are required for refractory materials, especially for nuclear fuel materials, because these data are important input parameters to carry out analysis of consequences of any off-normal events in liquid-metal–cooled fast-breeder reactors (LMFBRs). Conventional experimental techniques used to measure the vapor pressures below 2500 K cannot be used at very high temperatures (>3000 K) because of limitations arising from the need for a suitable sample container and difficulties in generation of very high temperatures. One way of avoiding these problems is to use a dynamic pulse-heating technique. Of the different methods, the laser pulse-heating technique is advantageous. We have developed a laser-induced vaporization–mass-spectrometry system and studied the vaporization behavior of nuclear fuel materials such as UO 2 , UC, and ThO 2 , and other technologically important materials such as graphite and Si 3 N 4 at very high temperat...

Indian Journal of Pure & Applied Physics, 2007

Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have com... more Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have compared the boron isotope distribution present in thin films of B 4 C that are formed by pulsed laser deposition using nanosecond (ns) and picosecond (ps) pulse Nd-YAG lasers. With the ns laser beam, in the plume we could observe an isotope ratio of 10 B/ 11 B as high as 0.9, but in the film we could hardly see any enrichment. With ps pulsed laser, the maximum value obtained for the 10 B/ 11 B ratio is about 0.29 in the film.

Nanoscience & Nanotechnology-Asia

Introduction: Intrinsic resistive switching properties of Pt/TiO2-x/TiO2/Pt crossbar memory array... more Introduction: Intrinsic resistive switching properties of Pt/TiO2-x/TiO2/Pt crossbar memory array has been examined using the crossbar (4×4) arrays fabricated by using DC/RF sputtering under specific conditions at room temperature. Materials and Methods: The growth of filament is envisaged from bottom electrode (BE) towards the top electrode (TE) by forming conducting nano-filaments across TiO2/TiO2-x bilayer stack. Non-linear pinched hysteresis curve (a signature of memristor) is evident from I-V plot measured using Pt/TiO2-x /TiO2/Pt bilayer device (a single cell amongst the 4×4 array is used). It is found that the observed I-V profile shows two distinguishable regions of switching symmetrically in both SET and RESET cycle. Distinguishable potential profiles are evident from I-V curve; in which region-1 relates to the electroformation prior to switching and region-2 shows the switching to ON state (LRS). It is observed that upon reversing the polarity, bipolar switching (set and r...

Radiochimica Acta

A double focusing ICP-MS with pulsed laser deposition (PLD) of thin films as sampling tool has be... more A double focusing ICP-MS with pulsed laser deposition (PLD) of thin films as sampling tool has been used in simulated spent fuels for a quick measurement on burn-up of nuclear reactor fuels by measuring the atom ratio of U (representing total heavy elements of mass >225) to selected lanthanide fission monitors. A linear correlation is established between the measured intensity ratios of 238U/143Nd, 238U/(145Nd+146Nd) and 238U/139La against the actual atom ratios present in the samples. The samples in the form of solution are obtained by dissolving different concentrations of U, Nd and La in nitric acid medium, representing a wide burn-up range (0.19 to 19.98 at.%). In addition, PLD films were deposited using 1064 nm, 100 ps Nd:YAG laser pulses on solid targets of U and Nd mixed oxide, corresponding to different burn-ups. ICP-MS analysis of these films after dissolving in nitric acid showed values close to that of the solid target composition. Burn-up data obtained with films depo...

Indian Journal of Pure and Applied Physics

Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have com... more Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have compared the boron isotope distribution present in thin films of B₄C that are formed by pulsed laser deposition using nanosecond (ns) and picosecond (ps) pulse Nd-YAG lasers. With the ns laser beam, in the plume we could observe an isotope ratio of ¹⁰B/¹¹B as high as 0.9, but in the film we could hardly see any enrichment. With ps pulsed laser, the maximum value obtained for the ¹⁰B/¹¹B ratio is about 0.29 in the film.

... chem. Soc. 70, 4165 (1948). 23. Bhatnagar S., Gupta S. and Shahi K., Solid St. lonics 31, 107... more ... chem. Soc. 70, 4165 (1948). 23. Bhatnagar S., Gupta S. and Shahi K., Solid St. lonics 31, 107 (1988). ... 11. S. Gupta, S. Patnaik, S. Chaklanobis and K. Shahi Solid St. Ionics 31 (1988), p. 5. Abstract | PDF (446 K) | View Record in Scopus | Cited By in Scopus (5). 12. ...

Solid State Ionics, 2001

Thin films of CaZrO3 are prepared by pulsed laser deposition (PLD) using a 532-nm Q-switched Nd:Y... more Thin films of CaZrO3 are prepared by pulsed laser deposition (PLD) using a 532-nm Q-switched Nd:YAG laser. Films prepared in vacuum, on annealing, revealed the structure of calcia stabilized zirconia, i.e. Ca0.15Zr0.85O1.85. Films prepared in the presence of 150×10−3 Torr of oxygen, on annealing, have CaZrO3 structure, though a small percentage of Ca0.15Zr0.85O1.85 is still present. Larger oxygen pressures during

International Journal of …, 2003

Industrial & Engineering Chemistry Research

Chemistry of Materials, 2000

ABSTRACT Sr- and Mg-doped LaGaO3 powders with various dopant concentrations (La1-xSrxGa1-yMgyO3-(... more ABSTRACT Sr- and Mg-doped LaGaO3 powders with various dopant concentrations (La1-xSrxGa1-yMgyO3-(x+y)/2 where 0.02 ≤ x ≤ 0.2 and 0.02 ≤ y ≤ 0.2) were synthesized through a novel solution combustion route. X-ray diffraction patterns indicate orthorhombic structure for compositions 0 ≤ x ≤ 0.075 and 0 ≤ y ≤ 0.075 and primitive − cubic for 0.1 ≤ x ≤ 0.2 and 0.1 ≤ y ≤ 0.2. Thin films of La1-xSrxGa1-yMgyO3-(x+y)/2 (0.1 ≤ x ≤ 0.2 and 0.1 ≤ y ≤ 0.2) were deposited using both Nd:YAG (532 nm) and excimer (248 nm) lasers. The as-deposited films at room temperature were amorphous, which on annealing at 973 K exhibited single-phase cubic structure. Films deposited with excimer laser were smooth and particulate free compared to Nd:YAG laser deposition. The LSGM films on Si[111] and sapphire[0001] substrates showed good surface morphology compared to films on MgO[001] and amorphous quartz. Films were found to be slightly rich in Sr/La ratio compared to target composition. O+, O, Ga+, Ga, and La+ were the major species in the laser ablation plume with ion and neutral velocities of 3 × 105 and 3 × 104 cm/s, respectively.

JOURNAL OF INFRARED AND MILLIMETER WAVES, 2009

The physical principle of laser induced breakdown spectroscopy(LIBS) was interpreted.How the pres... more The physical principle of laser induced breakdown spectroscopy(LIBS) was interpreted.How the pressure affects the laser induced plasma was analyzed.A LIBS experimental system for the low pressure condition was setup and the experiments at the different pressures were carried out.The experimental result expresses how the pressure affects the laser induced plasma quantitatively.The feasibility on the application of LIBS to lunar exploration was discussed.

Journal of Analytical Atomic Spectrometry, 2021

Resolving isobaric interference in situ using laser-ionization mass spectrometry (LIMS).

Spectrochimica Acta Part B: Atomic Spectroscopy, 2022

Materials Today: Proceedings, 2019

International Journal of Mass Spectrometry, 2015

Abstract Nd-YAG laser pulses of 1064, 532, 266 nm in wavelength and of 8 ns and 100 ps in pulse w... more Abstract Nd-YAG laser pulses of 1064, 532, 266 nm in wavelength and of 8 ns and 100 ps in pulse width as well as KrF excimer laser pulses (248 nm) of 30 ns pulse width were employed to deposit thin films of the simulated spent nuclear fuel pellets. The deposited thin films were dissolved in nitric acid and analyzed for residual heavy element (U) to burn-up monitor (Nd) ratio using isotopic dilution mass spectrometry (employing the TIMS technique) to determine the burn-up in these simulated fuel pellets. While the use of ns-laser pulses of 1064 nm wavelength resulted in high elemental fractionation with enhanced Nd concentration compared to the target composition, the 266 nm ps-laser pulses produce films with least elemental fractionation in the film and hence is best suited for this analytical application. Due to the very small amount of material in the deposited film and the amenability of pulsed laser deposition system for use in radioactive shielded hot cells, this analytical technique is suitable for sampling highly radioactive materials.

Vapor pressure data at ultrahigh temperatures (5000 K) are required for refractory materials, esp... more Vapor pressure data at ultrahigh temperatures (5000 K) are required for refractory materials, especially for nuclear fuel materials, because these data are important input parameters to carry out analysis of consequences of any off-normal events in liquid-metal–cooled fast-breeder reactors (LMFBRs). Conventional experimental techniques used to measure the vapor pressures below 2500 K cannot be used at very high temperatures (>3000 K) because of limitations arising from the need for a suitable sample container and difficulties in generation of very high temperatures. One way of avoiding these problems is to use a dynamic pulse-heating technique. Of the different methods, the laser pulse-heating technique is advantageous. We have developed a laser-induced vaporization–mass-spectrometry system and studied the vaporization behavior of nuclear fuel materials such as UO 2 , UC, and ThO 2 , and other technologically important materials such as graphite and Si 3 N 4 at very high temperat...

Indian Journal of Pure & Applied Physics, 2007

Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have com... more Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have compared the boron isotope distribution present in thin films of B 4 C that are formed by pulsed laser deposition using nanosecond (ns) and picosecond (ps) pulse Nd-YAG lasers. With the ns laser beam, in the plume we could observe an isotope ratio of 10 B/ 11 B as high as 0.9, but in the film we could hardly see any enrichment. With ps pulsed laser, the maximum value obtained for the 10 B/ 11 B ratio is about 0.29 in the film.

Nanoscience & Nanotechnology-Asia

Introduction: Intrinsic resistive switching properties of Pt/TiO2-x/TiO2/Pt crossbar memory array... more Introduction: Intrinsic resistive switching properties of Pt/TiO2-x/TiO2/Pt crossbar memory array has been examined using the crossbar (4×4) arrays fabricated by using DC/RF sputtering under specific conditions at room temperature. Materials and Methods: The growth of filament is envisaged from bottom electrode (BE) towards the top electrode (TE) by forming conducting nano-filaments across TiO2/TiO2-x bilayer stack. Non-linear pinched hysteresis curve (a signature of memristor) is evident from I-V plot measured using Pt/TiO2-x /TiO2/Pt bilayer device (a single cell amongst the 4×4 array is used). It is found that the observed I-V profile shows two distinguishable regions of switching symmetrically in both SET and RESET cycle. Distinguishable potential profiles are evident from I-V curve; in which region-1 relates to the electroformation prior to switching and region-2 shows the switching to ON state (LRS). It is observed that upon reversing the polarity, bipolar switching (set and r...

Radiochimica Acta

A double focusing ICP-MS with pulsed laser deposition (PLD) of thin films as sampling tool has be... more A double focusing ICP-MS with pulsed laser deposition (PLD) of thin films as sampling tool has been used in simulated spent fuels for a quick measurement on burn-up of nuclear reactor fuels by measuring the atom ratio of U (representing total heavy elements of mass >225) to selected lanthanide fission monitors. A linear correlation is established between the measured intensity ratios of 238U/143Nd, 238U/(145Nd+146Nd) and 238U/139La against the actual atom ratios present in the samples. The samples in the form of solution are obtained by dissolving different concentrations of U, Nd and La in nitric acid medium, representing a wide burn-up range (0.19 to 19.98 at.%). In addition, PLD films were deposited using 1064 nm, 100 ps Nd:YAG laser pulses on solid targets of U and Nd mixed oxide, corresponding to different burn-ups. ICP-MS analysis of these films after dissolving in nitric acid showed values close to that of the solid target composition. Burn-up data obtained with films depo...

Indian Journal of Pure and Applied Physics

Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have com... more Isotope enrichment in laser-ablated plume is an interesting phenomenon. In this work, we have compared the boron isotope distribution present in thin films of B₄C that are formed by pulsed laser deposition using nanosecond (ns) and picosecond (ps) pulse Nd-YAG lasers. With the ns laser beam, in the plume we could observe an isotope ratio of ¹⁰B/¹¹B as high as 0.9, but in the film we could hardly see any enrichment. With ps pulsed laser, the maximum value obtained for the ¹⁰B/¹¹B ratio is about 0.29 in the film.

... chem. Soc. 70, 4165 (1948). 23. Bhatnagar S., Gupta S. and Shahi K., Solid St. lonics 31, 107... more ... chem. Soc. 70, 4165 (1948). 23. Bhatnagar S., Gupta S. and Shahi K., Solid St. lonics 31, 107 (1988). ... 11. S. Gupta, S. Patnaik, S. Chaklanobis and K. Shahi Solid St. Ionics 31 (1988), p. 5. Abstract | PDF (446 K) | View Record in Scopus | Cited By in Scopus (5). 12. ...

Solid State Ionics, 2001

Thin films of CaZrO3 are prepared by pulsed laser deposition (PLD) using a 532-nm Q-switched Nd:Y... more Thin films of CaZrO3 are prepared by pulsed laser deposition (PLD) using a 532-nm Q-switched Nd:YAG laser. Films prepared in vacuum, on annealing, revealed the structure of calcia stabilized zirconia, i.e. Ca0.15Zr0.85O1.85. Films prepared in the presence of 150×10−3 Torr of oxygen, on annealing, have CaZrO3 structure, though a small percentage of Ca0.15Zr0.85O1.85 is still present. Larger oxygen pressures during

International Journal of …, 2003

Industrial & Engineering Chemistry Research

Chemistry of Materials, 2000

ABSTRACT Sr- and Mg-doped LaGaO3 powders with various dopant concentrations (La1-xSrxGa1-yMgyO3-(... more ABSTRACT Sr- and Mg-doped LaGaO3 powders with various dopant concentrations (La1-xSrxGa1-yMgyO3-(x+y)/2 where 0.02 ≤ x ≤ 0.2 and 0.02 ≤ y ≤ 0.2) were synthesized through a novel solution combustion route. X-ray diffraction patterns indicate orthorhombic structure for compositions 0 ≤ x ≤ 0.075 and 0 ≤ y ≤ 0.075 and primitive − cubic for 0.1 ≤ x ≤ 0.2 and 0.1 ≤ y ≤ 0.2. Thin films of La1-xSrxGa1-yMgyO3-(x+y)/2 (0.1 ≤ x ≤ 0.2 and 0.1 ≤ y ≤ 0.2) were deposited using both Nd:YAG (532 nm) and excimer (248 nm) lasers. The as-deposited films at room temperature were amorphous, which on annealing at 973 K exhibited single-phase cubic structure. Films deposited with excimer laser were smooth and particulate free compared to Nd:YAG laser deposition. The LSGM films on Si[111] and sapphire[0001] substrates showed good surface morphology compared to films on MgO[001] and amorphous quartz. Films were found to be slightly rich in Sr/La ratio compared to target composition. O+, O, Ga+, Ga, and La+ were the major species in the laser ablation plume with ion and neutral velocities of 3 × 105 and 3 × 104 cm/s, respectively.