24 results on '"A.S. Dhaliwal"'
Search Results
2. Absorption edge parameters of the L III edge for compounds of Hg, Tl, Pb and Bi using EDXRF technique
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Manoj Gupta, Amrit Singh, K.S. Kahlon, Gurinderjeet Singh, and A.S. Dhaliwal
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Radiation ,010308 nuclear & particles physics ,Chemistry ,Radioactive source ,Detector ,Analytical chemistry ,Edge (geometry) ,010403 inorganic & nuclear chemistry ,01 natural sciences ,0104 chemical sciences ,Absorption edge ,Attenuation coefficient ,0103 physical sciences ,Constant (mathematics) ,Effective atomic number - Abstract
The measurement of Absorption edge parameters of the L III edge of pure elements Hg, Tl, Pb and Bi along with their compounds HgCl2, HgO, HgF2, TlCl, Tl2O3, PbCl2, PbF2, Pb3O4, BiF3, BiCl3 and Bi2O3 has been done using EDXRF technique. In the present measurements 241Am (59.54 keV) radioactive source of activity 100 mCi along with CANBERRA make cryo-cooled Si (Li) detector is used. The measured results are compared with theoretically calculated values from FFAST version 2.1 (Chantler et al., 2005) and shows good agreement with each other within experimental uncertainties within 3.5%. It is observed that the values of absorption edge parameters of the LIII edge depends slightly on the chemical environment and shows almost constant behaviour with effective atomic number ( Z eff ) more...
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- 2018
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3. Dielectric characterization of rapeseed (Brassica napus L.) from 10 to 3000 MHz
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K.S. Mann, A.S. Dhaliwal, and Namita Bansal
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0106 biological sciences ,Materials science ,Rapeseed ,Moisture ,Loss factor ,Analytical chemistry ,Soil Science ,04 agricultural and veterinary sciences ,Dielectric ,Atmospheric temperature range ,040401 food science ,01 natural sciences ,0404 agricultural biotechnology ,Control and Systems Engineering ,010608 biotechnology ,Dielectric heating ,Penetration depth ,Agronomy and Crop Science ,Microwave ,Food Science - Abstract
Dielectric characterization of rapeseed ( Brassica napus L.) in the temperature range of 20–60 °C and at moisture contents of 8.5, 12.5 and 16% wet basis (w.b.) was performed by determining the dielectric constant and loss factor at frequencies from 10 to 3000 MHz. This range of frequencies includes the ISM (Industrial, Scientific and Medical) frequencies of 13, 27, 40, 915 and 2450 MHz. An open-ended coaxial probe (Speag DAK, 12) and a vector network analyzer (Agilent Technologies, E5071C) were used to measure the dielectric properties (dielectric constant and loss factor). Compressed ground samples of rapeseed at densities nearly equivalent to seed density were used. Determined data at the ISM frequencies was fitted to polynomials to represent the dependence of the dielectric constant as well as the loss factor on temperature and moisture content. The calculated penetration depth of the electromagnetic field in rapeseed at the ISM frequencies shows that at a given moisture content and temperature, it decreases with increasing frequency. The reported data are useful in designing and developing radio-frequency (RF) and microwave (MW) applicators for dielectric heating of rapeseed. more...
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- 2016
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4. Measurement of LIII jump ratio, jump factor and related parameters for Pt and Tl
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Manoj Kumar Gupta, Amrit Singh, Gurinderjeet Singh, K.S. Kahlon, and A.S. Dhaliwal
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Photon ,010308 nuclear & particles physics ,Oscillator strength ,Chemistry ,Mechanical Engineering ,Attenuation ,Detector ,Metals and Alloys ,Analytical chemistry ,High resolution ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Jump ratio ,Mechanics of Materials ,0103 physical sciences ,Materials Chemistry ,Jump ,Atomic physics ,0210 nano-technology ,Excitation - Abstract
L III jump ratio, jump factor and its related parameters for Pt and Tl have been measured by using photons of energy 59.54 keV from 241 Am source. The measurements are made by using gamma attenuation method in secondary excitation geometry with high resolution (155 eV at 5.9 keV) Si(Li) detector. X-rays energies, above and below the L III edge for the targets of Pt and Tl are obtained by using secondary target of Br, Co, Cu, Fe, Ga, Ni, Pt, Se, Sr, Tl and Zn. The measurements are compared with the theoretical values of total attenuation cross-sections, L III Jump ratio, jump factor; Davisson–Krichner ratio and L III sub-shell oscillator strength obtained by using mass attenuation coefficients from WinXCom. It is observed that the measured values are in good agreement with theoretical results. These measurement shall enhances the understanding of material characteristics of Pt and Tl, as these are widely used in biological, chemical, medical, electronics and petroleum industry. more...
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- 2016
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5. Dielectric properties of corn flour from 0.2 to 10GHz
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A.S. Dhaliwal, Namita Bansal, and K.S. Mann
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Electromagnetic field ,Materials science ,Quality (physics) ,Moisture ,Loss factor ,Analytical chemistry ,Dielectric ,Thermal treatment ,Microwave ,Food Science ,Grinding - Abstract
A modified form of existing geometrical set-up of sample holder and coaxial line probe which is coupled with Agilent E5071C vector network analyzer, is used to determine the dielectric constant e ′ and loss factor e ″ of corn flour at tapped densities 0.69, 0.63, 0.54 and 0.46 g/cm 3 that correspond to moisture contents 8.8%, 12.6%, 17.4% and 22.7% wet basis respectively; and in the temperature and frequency ranges 25–75 °C and 0.2–10 GHz respectively. Measurements made at tapped density helps in designing microwave (MW) applicators as this density remains almost unchanged under unintentionally produced mechanical impacts, when flour is transported from grinding unit to applicators. Results show that e ′ decreases smoothly with increase in frequency at all temperatures and tapped densities, while e ″ decreases up to ∼1 GHz and then starts increasing. At a given frequency, change in both e ′ and e ″ with tapped density does not follow a particular trend for temperatures up to 50 °C; while increasing trend with decrease in tapped density is observed above 50 °C. Under strict controlled conditions such as power of electromagnetic field, exposure time, and desired maximum temperature of corn flour to get the acceptable quality of flour, these dielectric properties are beneficial to develop MW applicators for the purpose of thermal treatment to flour. more...
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- 2015
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6. Measurement of absorption edge parameters near K edge for the compounds of Zn, Zr, Cd, Ba and Pb
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Gurinderjeet Singh, A.S. Dhaliwal, Manoj Kumar Gupta, and K.S. Kahlon
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Ligand ,Chemistry ,Mechanical Engineering ,Chemical structure ,Metals and Alloys ,Analytical chemistry ,Gamma ray ,Electron shell ,Jump ratio ,Absorption edge ,K-edge ,Mechanics of Materials ,Materials Chemistry ,Effective atomic number - Abstract
Effect of chemical environment on the K shell absorption edge parameters i.e. jump factor ( J K ), jump ratio ( r K ) and number of protons in terms of effective atomic number ( Z eff ) has been measured from the study of interaction of photons with pure elements (Zn, Zr, Cd, Ba, Pb) and their compounds [Zn(CH 3 COO) 2 , ZnSO 4 , ZnCl 2 , ZnO, Zr(OH) 4 , ZrN, ZrO 2 , ZrOCl 2 , CdCl 2 , CdCO 3 , Cd(NO 3 ) 2 , Cd(OH) 2 , BaSO 4 , BaCl 2 , Ba(NO 3 ) 2 , BaCO 3 , BaCl 2 ⋅2H 2 O, PbCl 2 , PbO, PbCO 3 , Pb(NO 3 ) 2 , Pb 3 O 4 , Pb(CH 3 COO) 2 ⋅3H 2 O] using Si(Li) detector and EDXRF technique. 59.54-keV gamma ray photons from 241 Am radioactive source have been used for the measurement of K shell absorption edge parameters J K , r K and Z eff . Different values of J K , r K and Z eff have been measured for the same element with different ligands group in the given elemental compounds. All measured results were compared with theoretically calculated values from WinXCOM (Gerward et al., 2001). It is found that measured values are in agreement with the theoretical values within experimental uncertainties of 6%. It is observed that the J K , r K and Z eff are affected in the different chemical environment due to presence of ligand group attached with element. Maximum change in the values of J K , r K and Z eff are observed in case of compounds containing –Cl 2 & –(CH 3 COO) 2 as a ligand group. Further, maximum variation of >20% in the Z eff for Zn and Pb compounds is also observed. From the present measurements, it is found that the J K , r K and Z eff depend on the chemical environment of the compound under investigation. These parameters may be helpful to understand the physical behavior and chemical structure of the compounds. more...
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- 2015
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7. High Electronic Excitation Induced Modifications by 120 MeV Ni9+ Ions in Ag-Polypyrrole Composite Films: A Comparative Study
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Yasir Ali and A.S. Dhaliwal
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chemistry.chemical_compound ,Materials science ,chemistry ,Chemical engineering ,Composite number ,Analytical chemistry ,Polypyrrole ,Excitation ,Ion - Published
- 2015
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8. Measurement of attenuation coefficient, effective atomic number and electron density of oxides of lanthanides by using simplified ATM-method
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Manoj Kumar Gupta, Gurinderjeet Singh, A.S. Dhaliwal, and K.S. Kahlon
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Lanthanide ,Electron density ,Chemistry ,Mechanical Engineering ,Attenuation ,Metals and Alloys ,Analytical chemistry ,Electron ,Mechanics of Materials ,Attenuation coefficient ,Materials Chemistry ,Mass attenuation coefficient ,Atomic number ,Effective atomic number - Abstract
The linear and mass attenuation coefficient of non-uniform thick samples of oxides of lanthanide (Pr6O11, Nd2O3, Gd2O3, Tb4O7, Ho2O3 and Er2O3) has been measured by gamma ray photons of energy 59.54 keV obtained from 100 mCi radioactive source of 241Am. Advanced Two Media (ATM) methods Gupta et al. (2013) is simplified by considering air as first medium and metallic foil as second medium. In the present measurements this consideration simplifies the mathematical complexities and laboratory work to find the attenuation coefficients of non-uniform thick samples. The values of attenuation coefficient were then used to calculate effective atomic numbers (Zeff), interaction cross-section (σ) and effective electron densities (Neff) of lanthanide oxides. The method is validated by measuring linear/mass attenuation coefficient and other parameters for Mo, Ag, Sn, W and Pb of uniform thickness. The measured results are compared with the theoretical values from WinXcom Gerward et al. (2001). It is found that measured values are in agreement within 2% of theoretical results. The measurement of linear attenuation coefficient, effective atomic numbers (Zeff), interaction cross-section and effective electron densities (Neff) enhances the understanding of material characteristics. Presently studied materials i.e. oxides of Lanthanide are widely used as glass colouring agent and in electronic sensing devices. more...
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- 2015
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9. Measurement of L3 subshell absorption edge parameters in the elements of lanthanide series (Z=57–70)
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Gurinderjeet Singh, K.S. Kahlon, A.S. Dhaliwal, and Manoj Kumar Gupta
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Lanthanide ,Jump ratio ,Radiation ,Absorption edge ,Chemistry ,Jump ,Analytical chemistry ,NIST - Abstract
An experimental measurement has been carried out for measuring the absorption edge parameters i.e. jump ratio and jump factor for elements of lanthanide series “La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb” ( Z =57–70) by using an EDXRF technique. Measured values of such parameters have been compared with theoretical values to check the experimental uncertainties and it was found that experimental results are in good agreement with theoretical values of Chantler et al. (2005, 〈 http://physics.nist.gov/ffast 〉, NIST, Gaithersburg). more...
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- 2014
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10. Swift heavy ions induced surface modifications in Ag-polypyrrole composite films synthesized by an electrochemical route
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Vijay Kumar, H.C. Swart, Yasir Ali, Kashma Sharma, R. G. Sonkawade, Vinod Kumar, and A.S. Dhaliwal
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Nuclear and High Energy Physics ,Materials science ,Scanning electron microscope ,Composite number ,Analytical chemistry ,Polypyrrole ,Fluence ,Indium tin oxide ,chemistry.chemical_compound ,symbols.namesake ,Swift heavy ion ,chemistry ,symbols ,Irradiation ,Raman spectroscopy ,Instrumentation - Abstract
The general aim of this work was to study the effects of swift heavy ions on the properties of electrochemically synthesized Ag-polypyrrole composite thin films. Initially, polypyrrole (PPy) films were electrochemically synthesized on indium tin oxide coated glass surfaces using a chronopotentiometery technique, at optimized process conditions. The prepared PPy films have functioned as working electrodes for the decoration of submicron Ag particles on the surface of the PPy films through a cyclicvoltammetry technique. Towards probing the effect of swift heavy ion irradiation on the structural and morphological properties, the composite films were subjected to a 40 MeV Li 3+ ion beam irradiation for various fluences (1 × 10 11 , 1 × 10 12 and 1 × 10 13 ions/cm 2 ). Comparative microstructural investigations were carried out after the different ion fluences using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy and micro-Raman spectroscopy techniques. Raman and SEM studies revealed that the structure of the films became disordered after irradiation. The SEM studies of irradiated composite films show significant changes in their surface morphologies. The surface was smoother at lower fluence but craters were observed at higher fluence. more...
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- 2014
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11. Gamma radiation induced modifications in Au-polypyrrole nanocomposites: Detailed Raman and X-ray studies
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H.C. Swart, R. G. Sonkawade, A.S. Dhaliwal, Yasir Ali, and Vijay Kumar
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Materials science ,Nanocomposite ,Scanning electron microscope ,Composite number ,X-ray ,Analytical chemistry ,Condensed Matter Physics ,Polypyrrole ,Surfaces, Coatings and Films ,symbols.namesake ,chemistry.chemical_compound ,chemistry ,symbols ,Crystallite ,Irradiation ,Raman spectroscopy ,Instrumentation - Abstract
A facile electrochemical synthesis of Au-polypyrrole (Au-PPy) composite films has been reported. The synthesized composite films were irradiated with a 1.25 MeV Co-60 gamma radiation with doses ranging from 500 to 1500 kGy and the corresponding changes in structural properties of the composites were studied. The structural investigation of Au-PPy composite films were performed by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and micro-Raman spectroscopic techniques. XRD studies showed the variation in peak intensities after gamma irradiation. Different parameters like crystallite size, micro strain, dislocation density and distortion parameters were calculated from XRD spectra. Observed results indicate the formation of an ordered system in the irradiated composite films. SEM micrograph showed significant interactions between the Au-particles and PPy film after gamma irradiation. Raman spectra show an overall increase in peak intensity after gamma irradiation. more...
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- 2014
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12. Swift heavy ion induced modifications in metal conducting polymer composite films
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R. G. Sonkawade, A.S. Dhaliwal, and Yasir Ali
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Nuclear and High Energy Physics ,Materials science ,Physics::Instrumentation and Detectors ,Scanning electron microscope ,Physics::Medical Physics ,Analytical chemistry ,Electrochemistry ,Ion ,symbols.namesake ,Swift heavy ion ,symbols ,Irradiation ,Dislocation ,Thin film ,Raman spectroscopy ,Instrumentation - Abstract
Au–polyaniline (Au–PANI) thin films were prepared by an electrochemical process. Au–PANI films were irradiated with 100 MeV O7+ and 120 MeV Ni9+ ion beams with fluences varying from 3 × 1011 ions/cm2 to 3 × 1012 ions/cm2. The effects of heavy ions on the structural, chemical and morphological properties of the composite films were studied by using X-ray diffraction, Raman and scanning electron microscopy techniques. X-ray spectra showed the gradual decrease in the peak intensity after irradiation. The interchain distance, interplanar distance, micro strain, dislocation density and distortion parameters were calculated. The analysis revealed a noticeable changes in these parameters after irradiation for both cases. The results showed the formation of clusters with a porous structure after irradiation. The effect of irradiation was greater in case of 120 MeV Ni9+ rather than 100 MeV O7+ ions due to their high electronic energy loss in Au–PANI. I–V characteristic measurements were carried out as a function of ion fluence. The results are discussed on the basis of linear energy transfer (LET) of the irradiated ions. more...
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- 2013
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13. Polypyrrole microspheroidals decorated with Ag nanostructure: Synthesis and their characterization
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Vijay Kumar, Kashma Sharma, Yasir Ali, R. G. Sonkawade, and A.S. Dhaliwal
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Nanostructure ,Materials science ,Scanning electron microscope ,Analytical chemistry ,General Physics and Astronomy ,Surfaces and Interfaces ,General Chemistry ,Substrate (electronics) ,Condensed Matter Physics ,Polypyrrole ,Surfaces, Coatings and Films ,Indium tin oxide ,symbols.namesake ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,symbols ,Surface modification ,Fourier transform infrared spectroscopy ,Raman spectroscopy - Abstract
In this work, polypyrrole (PPy) microspheroidals were synthesized by chronopotentiometry on conducting indium tin oxide (ITO) substrate. These prepared PPy microspheroidals were subjected to surface modification by Ag nanostructures using cyclic voltammetery (CV). The decoration of Ag nanostructures on PPy surface was characterized by UV–visible spectroscopy (UV–vis), X-ray diffraction (XRD), Fourier transform infrared (FTIR), energy dispersion X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). SEM images show nanostar like structures with slight aggregation of Ag nanostructures on the PPy surface. The average particle size of PPy was found to increase from 7.3 to 30 nm after decoration with Ag nanostructure. Further, the XRD patterns shows a decrease in interchain separation and inter planar distance after the impregnation of Ag nanostructures in the PPy film when compared with pure PPy film. FTIR and Raman spectra displayed main vibrational bands; including the characteristic peaks. Raman spectra also show the signature of polaron and bipolaron states. Electrical conductivity of the Ag nanostructure decorated PPy microspheroidals has been measured by the two probe method. A possible mechanism for the formation of Ag-PPy nanostructure has been proposed. more...
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- 2013
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14. Effect of swift heavy ion beam irradiation on Au–polyaniline composite films
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R. G. Sonkawade, Yasir Ali, A.S. Dhaliwal, and Vijay Kumar
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Materials science ,Working electrode ,Ion beam ,Scanning electron microscope ,Composite number ,Ultra-high vacuum ,Analytical chemistry ,Condensed Matter Physics ,Surfaces, Coatings and Films ,symbols.namesake ,Swift heavy ion ,symbols ,Irradiation ,Raman spectroscopy ,Instrumentation - Abstract
In this paper, two-step electrochemical synthesis method is reported for the fabrication of Au–polyaniline (Au–PANI) composite film. Initially, PANI film was electrochemically synthesized by using chronopotentiometery with optimized process parameters on platinum electrode. The synthesized PANI film acts as working electrode for the decoration of Au particles on the surface of PANI film by using cyclovoltammetry (CV) technique. Later, these films were irradiated under high vacuum (∼5 × 10−6 Torr) at room temperature with 40 MeV C5+ ion beam at various fluences ranging from 1 × 1011 to 1 × 1013 ions/cm2. The Au–PANI composite films were characterized before and after irradiation by using micro-Raman, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The characteristic peaks of the Raman spectrum of Au–PANI composite films were reduced after irradiation. XRD spectra exhibited the decrease in the peak intensity. Moreover, interchain distance, interplanar distance, micro strain, dislocation density and distortion parameters were calculated. The analysis revealed a significant variation in these parameters with an increase in the ion fluence, which is in line with the Raman analysis. SEM shows the formation of clusters with porous structure after irradiation. more...
- Published
- 2013
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15. Gamma irradiation induced chemical and structural modifications in PM-355 polymeric nuclear track detector film
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R. G. Sonkawade, A.S. Dhaliwal, and Vijay Kumar
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Nuclear and High Energy Physics ,Materials science ,Analytical chemistry ,Gamma ray ,Crystallinity ,symbols.namesake ,symbols ,Direct and indirect band gaps ,Crystallite ,Irradiation ,Dislocation ,Spectroscopy ,Raman spectroscopy ,Instrumentation - Abstract
This experimental study investigated the modification of chemical and structural properties of PM-355 films by irradiation of 1.25 MeV 60Co γ-radiations at doses ranging from 0–675 kGy. The induced modifications were followed by micro-Raman and X-ray diffraction (XRD) spectroscopy. Further, the induced modifications were confirmed by UV–Visible spectroscopy. Raman spectra show that the films are highly disordered at the highest gamma dose. The XRD pattern of PM-355 shows the decreasing intensity of peak positions with an increase in the gamma dose, which suggests the loss of crystallinity of the films due to irradiation. Observed results indicate the formation of a disordered system in the irradiated films. Furthermore, the crystallite size for pristine and bombarded sample has been calculated. Moreover, interchain distance, micro strain, interplanar distance, dislocation density and distortion parameters were calculated. The analysis revealed a significant increase in micro strain, dislocation density and distortion parameters with an increase of gamma dose, which is in line with the Raman analysis. With increasing γ-dose, the value of the direct and indirect band gap found to decrease. To the best of our knowledge, this work is the first to show the simultaneous existence of direct as well as the indirect band gap in PM-355 polymer. more...
- Published
- 2012
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16. High electronic excitation induced modifications by 100MeV O7+ and 150MeV Ni11+ ions in Makrofol KG polycarbonate film
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A.S. Dhaliwal, Vijay Kumar, and R. G. Sonkawade
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Nuclear and High Energy Physics ,Crystallinity ,Materials science ,Band gap ,Infrared ,Analytical chemistry ,Irradiation ,Fourier transform infrared spectroscopy ,Instrumentation ,Fluence ,Spectral line ,Ion - Abstract
Makrofol-KG polycarbonate (M-KG PC) films are irradiated with 150 MeV Ni 11+ and 100 MeV O 7+ ion beams at various fluences ranging from 1 × 10 11 to 3 × 10 12 ions/cm 2 . We have investigated the effect of irradiation parameters such as energy and ions fluence on optical, structural and chemical properties of the studied polymer, respectively. UV–Visible, Fourier Transform Infrared (FTIR) and X-ray diffraction (XRD) spectral studies have been employed in the present investigation. UV–Visible spectra exhibit a shift towards the higher wavelength regime after irradiation. This shift clearly reflects decrease in optical band gap after irradiation. The FTIR spectrum shows a decrease in intensity of the typical bands whereas the formation of new bands indicates the degradation of the polymer after irradiation. The XRD pattern of M-KG PC shows the decreasing intensity of peak positions with increase in ions fluence, which suggests loss of crystallinity of the films due to irradiation. Observed results indicate the formation of disordered system in the irradiated films. Magnitude of effect of irradiation is greater in case of 150 MeV Ni 11+ rather than 100 MeV O 7+ ions due to high electronic energy loss of Ni 11+ ions in M-KG PC. The results can be correlated on the basis of linear energy transfer (LET) of the irradiated ions. more...
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- 2012
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17. Carbon ion beam induced modifications of optical, structural and chemical properties in PADC and PET polymers
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S. K. Chakarvarti, R. G. Sonkawade, A.S. Dhaliwal, Paramjit Singh, and Vijay Kumar
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Radiation ,Materials science ,Photoluminescence ,Ion beam ,Absorption edge ,Analytical chemistry ,Irradiation ,Fourier transform infrared spectroscopy ,Spectroscopy ,Fluence ,Ion - Abstract
We report a study on the carbon ion beam induced modifications on optical, structural and chemical properties of polyallyl diglycol carbonate (PADC) commercially named as CR-39 and Polyethyleneterepthalate (PET) polymer films. These films were then irradiated by 55 MeV C 5+ ion beam at various fluences ranging from 1×10 11 to 1×10 13 ions/cm 2 . The pristine as well as irradiated samples were subjected to UV–Visible spectral study (UV–Vis), Photoluminescence (PL), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. It has been found that ion irradiation may induce a sort of defects in the polymers due to chain scission and cross linking as observed from PL spectral study. It is revealed from UV–Vis spectra absorption edge shifted towards longer wavelength region after irradiation with increasing ion fluence. This shift clearly reflects decrease in optical band gap. The XRD study indicates the gradual decrease in intensity in case of PADC with increasing ion fluence. However, the intensity pattern increased in case of PET at fluence of 10 11 ion/cm 2 then decreased with further increase in fluence. Crystalline size of PADC was found to be decreasing gradually with increase of ion fluence. Whereas, the crystalline size of PET films found to increase with lower fluence and decreases with higher ion fluence. FTIR spectrum also shows the change in intensity of the typical bands after irradiation in the both the polymers. The results so obtained can be used successfully in heavy ions dosimetry using well reported techniques. more...
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- 2012
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18. Study of mass attenuation coefficients, effective atomic numbers and electron densities for some low Z compounds of dosimetry interest at 59.54keV incident photon energy
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K.S. Mann, A.S. Dhaliwal, Baltej Singh Sidhu, and K.S. Kahlon
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Materials science ,Cyclohexane ,Attenuation ,Xylene ,Analytical chemistry ,Electron ,Photon energy ,chemistry.chemical_compound ,Nuclear Energy and Engineering ,chemistry ,Atomic number ,Mass attenuation coefficient ,Atomic physics ,Acetophenone - Abstract
Total mass attenuation coefficient, total photon interaction cross-section, effective atomic numbers ( Z eff ) and electron densities ( N e ) of Aniline (C 6 H 5 NH 2 ), Cyclohexane (C 6 H 12 ), Glycerine (C 3 H 5 (OH) 3 ), Butyl alcohol N-(C 4 H 9 OH), DMSO – dimethyl sulfoxide (C 2 H 6 OS), Methyl ethyl-ketone (C 4 H 8 O), Xylene (C 8 H 10 ), Acetophenone (C 8 H 8 O) and Triethyl amine (C 6 H 15 N) have been measured at 59.54 keV energy photon emitted by 100 mCi 241 Am point source employing narrow beam transmission geometry. Obtained results have been compared with theoretically calculated values of XCOM (Berger and Hubbel, 1987) and FFAST ( Chantler et al., 2005 ). Mixture rule was employed to calculated theoretical mass attenuation coefficient values for each sample. Good agreement has been observed between experimental and theoretical values within experimental uncertainties. more...
- Published
- 2012
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19. Study of optical, structural and chemical properties of neutron irradiated PADC film
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R. G. Sonkawade, K. Kant, Neelam Singh, Pawan K. Kulriya, A.S. Dhaliwal, S. K. Chakarvarti, and Vijay Kumar
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Crystallinity ,Materials science ,Photoluminescence ,Analytical chemistry ,Neutron ,Crystallite ,Irradiation ,Fourier transform infrared spectroscopy ,Condensed Matter Physics ,Instrumentation ,Fluence ,Scherrer equation ,Surfaces, Coatings and Films - Abstract
We have investigated neutron irradiation effects on the optical, structural and chemical properties of polyallyl diglycol carbonate (PADC) polymer, commercially named as CR-39. For this purpose, PADC samples were exposed with 4 MeV Am–Be neutron source at fluences varying from 2.36 × 10 6 to 5.94 × 10 7 n/cm 2 . The modifications so induced were analyzed using UV–Visible spectroscopy, X-ray diffraction Measurement (XRD), Photoluminescence (PL) and Fourier Transform infrared (FTIR) spectroscopy in the total attenuation reflection (ATR) mode. UV–Vis spectra of pristine and neutron irradiated PADC polymer sheets exhibit a decreasing trend in optical band gap. This decline in optical band gap with increasing fluence has been discussed on the basis of neutron irradiation induced defects in PADC. The XRD pattern of PADC shows the decreasing intensity of peak positions with increasing in fluence, which suggest that semicrystallinity of PADC changes slightly to amorphous phase after irradiation. At low fluence, crystallinity was found to increase but at higher fluence, it decreased which could be ascribed to neutron- induced defects in the polymer samples. Crystallite size calculated using Scherrer formula indicates a change and reflects the formation of disordered system in the irradiated polymer samples. The PL spectra show that the intensity of PL peak decreased with increase in fluence, which may be due to the disordered system via creation of defects in the irradiated polymer. The FTIR spectrum shows an overall reduction in intensity of the typical bands, indicating the degradation of PADC polymer after irradiation. These results so obtained can be used successfully in dosimetery using well reported protocols. more...
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- 2011
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20. Measurement of K-shell absorption edge jump factors and jump ratios of some medium Z elements using EDXRF technique
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A.S. Dhaliwal, K.S. Mann, K.S. Kahlon, and Baltej Singh Sidhu
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Radiation ,Absorption edge ,Chemistry ,Point source ,Astrophysics::High Energy Astrophysical Phenomena ,Excited state ,Detector ,Electron shell ,Jump ,Analytical chemistry ,Atomic physics ,Absorption (electromagnetic radiation) ,Fluorescence - Abstract
Energy dispersive X-ray fluorescence technique (EDXRF) has been employed for measuring K-shell absorption jump factors and jump ratios in elements Mn, Fe, Co, Cu, Zn, As and Sr using an X-PIPS Si(Li) detector. 90° reflection geometry has been used to detect the emitted fluorescent K X-rays from the target elements excited by 59.54 keV gamma-rays emitted from an 241 Am radioactive point source. Measured values of these parameters have been compared with different theoretically calculated as well as with other available experimental values. It is found that the present results fairly agree with theoretically calculated and experimental values within experimental uncertainties. more...
- Published
- 2011
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21. Measurements of L3-subshell absorption jump ratios and jump factors of Pb, Th and U
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Baltej Singh Sidhu, K.S. Kahlon, A.S. Dhaliwal, and K.S. Mann
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Radiation ,Chemistry ,Analytical chemistry ,Jump ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Absorption (electromagnetic radiation) ,Spectroscopy ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Abstract
L 3 -subshell absorption jump ratios and jump factors of Pb, Th and U have been measured by using EDXRF spectroscopy technique. Measured values of jump factors and jump ratios of Pb, Th and U are compared with theoretical values obtained from WinXcom programme [Radiat. Phys. Chem. 2001 (60) 23] and Chantler et al. [18] ( http://physics.nist.gov/ffast ). The experimental results are in agreement with the theoretical values within uncertainties of measurements. The measured values of jump factors and jump ratios are reported for the first time. more...
- Published
- 2011
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22. Effect of external magnetic field on attenuation coefficient for magnetic substances
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A.S. Dhaliwal, Manoj Kumar Gupta, and K.S. Kahlon
- Subjects
Paramagnetism ,Radiation ,Photon ,Condensed matter physics ,Ferromagnetism ,Chemistry ,Attenuation coefficient ,Non-blocking I/O ,Gamma ray ,Analytical chemistry ,Diamagnetism ,Magnetic field - Abstract
The measurement of attenuation coefficient of some magnetic substances, to include diamagnetic: Cu, Zn, Ag, Te, Au, Pb, and Perspex; paramagnetic: Al, Ti, Mo, Dy, Ho, and Pt and ferromagnetic substances: Fe, Co, Ni, Gd, FeO, NiO, FeS, and Fe 2 O 3, both in the presence and absence of an external magnetic field has been carried out using narrow beam transmission geometry by using gamma ray photons of incident energy 59.54 keV from 100 mCi, 241 Am point source. It was observed very keenly that the value of linear attenuation coefficient of various substances mentioned above decreased remarkably. It varied in the range of 1–2%, 2–6% and 6–9% for diamagnetic, paramagnetic and ferromagnetic substances respectively in the presence of an external magnetic field. Measured results elucidated it very clearly that linear attenuation coefficient at H= 0 T, 0.6 T and 1.2 T continued to decrease with a regular increase of magnetic field. It is also manifested that measurements of linear attenuation coefficient is not affected with the change in thickness of the given substance. Within error limits (1–3%) variations are observed with increases of thickness along with magnetic field. Further to it the obtained results of linear attenuation coefficient without magnetic field ( H= 0 T) were compared with theoretical data tables of FFAST and WinXCOM. It was established that values obtained are well within the experimental errors. To the best of our knowledge no other study in relation to the effect of linear attenuation coefficient in the presence of magnetic field available as precedence. more...
- Published
- 2014
23. Raman spectral study of electrochemically synthesized aupolyaniline composite
- Author
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A.S. Dhaliwal, Yasir Ali, R. G. Sonkawade, and Vijay Kumar
- Subjects
Conductive polymer ,Materials science ,Polyaniline nanofibers ,Scanning electron microscope ,Composite number ,Analytical chemistry ,Substrate (electronics) ,symbols.namesake ,chemistry.chemical_compound ,chemistry ,Polyaniline ,symbols ,Raman spectroscopy ,Dispersion (chemistry) - Abstract
In this report, a two step electrochemical synthesis of Au-polyaniline composite is explored. In the first step polyaniline film was deposited on the ITO coated glass substrate by using chronopotentiometery technique. Later, using CV the surface of as prepared film was decorated by Au particles to fabricate Au-polyaniline composite. The composite is characterized by Raman spectroscopy, XRD and SEM. The SEM analysis shows a uniform dispersion of Au particles on the porous polyaniline film. A Raman spectrum confirms the existence of polyaniline in different oxidation states, which are attributed to specific signatures of delocalized charge carriers. XRD spectra confirmed Bragg's reflection at various planes. more...
- Published
- 2013
- Full Text
- View/download PDF
24. 120 MeV Ni Ion beam induced modifications in poly (ethylene terephthalate) used in commercial bottled water
- Author
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R. G. Sonkawade, Vijay Kumar, A.S. Dhaliwal, and Yasir Ali
- Subjects
Crystallinity ,chemistry.chemical_compound ,Materials science ,Ion beam ,chemistry ,Absorption spectroscopy ,Analytical chemistry ,Polyethylene terephthalate ,Infrared spectroscopy ,Irradiation ,Fourier transform infrared spectroscopy ,Ion - Abstract
We report the effects of heavy ion irradiation on the optical, structural, and chemical properties of polyethylene terephthalate (PET) film used in commercial bottled water. PET bottles were exposed with 120 MeV Ni ions at fluences varying from 3 × 1010 to 3 × 1012 ion/cm2. The modifications so induced were analyzed by using UV-Vis, X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. Substantial decrease in optical band gap is observed with the increase in ion fluence. In the FTIR spectra, most of bands are decreased due the degradation of the molecular structure. XRD measurements show the decrease in peak intensity, which reflects the loss of crystallinity after irradiation. more...
- Published
- 2012
- Full Text
- View/download PDF
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