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We reported the physical properties of undoped and Aluminium doped ZnO (AZO) thin films that were synthesized by the RF magnetron sputtering method on a quartz substrate. The effect of dopant concentration on structure, morphology, optical and electrical properties of the thin films have been studied systematically by XRD, Raman spectroscopy, AFM, FE-SEM, UV-VIS spectroscopy and I-V measurement (two probe method) respectively. The crystallite growth of the thin films is along c-axis (002) orientations with hexagonal wurtzite structure. The crystallinity is enhanced in the 1%AZO thin films as compared to undoped ZnO. The transition of stress value after introducing the dopant is discussed. These changes are further correlated with the observed morphological changes. The alteration in optical transmission and optical band gap is also discussed extensively. For the AZO (1% and 2%) thin films the n-type conductivity and ohmic nature measured by using Keithley two probe set up. The responsible mechanism for improved conductivity is discussed. In the FTIR spectrum the peaks originated by the tetrahedral coordination of ZnO are observed which further confirms the wurtzite structure of the deposited thin film sample that are recorded by the XRD pattern.

Semi-crystalline films (100 μ m) of the non-conducting polymer polyethylene terephthalate (PET) were exposed to swift heavy ions of 45 MeV Li3+ (S e=7.29E+00 eV/A) and 120 MeV Au9+ (S e=1.157E+03 eV/A) at ion fluence ranging from 1010 to 1012 ions/cm2. The chemical and structural properties were investigated using Fourier transform infra-red (FTIR) spectroscopy and X-ray diffraction techniques. The optical studies were carried out by UV–visible spectroscopy. It was noticed that the value of the band gap decreases with increasing fluence and depends on energy loss during interaction. A significant loss of crystallinity and change in the size of the particle are observed in irradiated PET. FTIR studies of the samples show the chemical changes after irradiation. The atomic force microscopy observation revealed that the surface morphology changes after irradiation.

In the present study, the effects of swift heavy ion beam irradiation on the structural, chemical and optical properties of Makrofol solid-state nuclear track detector (SSNTD) were investigated. Makrofol-KG films of 40 μm thickness were irradiated with oxygen beam (O8 + ) with fluences ranging between 1010 ion/cm2 and 1012 ion/cm2. Structural, chemical and optical properties were investigated using X-ray diffraction, FTIR spectroscopy and UV–visible spectroscopy methods. It is observed that the direct and indirect band gaps of Makrofol-KG decrease after the irradiation. The XRD study shows that the crystalline size in the films decreases at higher fluences. The intensity plots of FTIR measurements indicate the degradation of Makrofol at higher fluences. Roughness of the surface increases at higher fluence.

This experimental study investigated the modification of optical, structural and morphological prop- erties of Makrofol-KG and Polyethylene Terephtalate (PET) by irradiation of 120 MeV Ni þ9 ions at fluences ranging from 1 � 10 10 to 1 � 10 12 ion/cm 2 . Optical and structural properties were studied by UV-visible spectros- copy and X-ray diffraction (XRD) method, respectively. XRD studies of pristine and irradiated polymers revealed that crystallinity decreased after irradiation with swift heavy ions. The UV-visible spectrum displayed a shift in absorbance edge toward higher wavelength at higher flu- ence, which can be correlated with transition involved in polymers. Fourier transform infrared spectroscopy spectra were analyzed to investigate the changes in the chemical/ structural properties of these polymers. The Makrofol-KG is found to exhibit more pronounced modification com- pared to PET after irradiation by swift heavy ions. The surface morphology studied by atomic force microscopy showed that the roughness of polymers surface increased with increasing fluence. V C 2011 Wiley Periodicals, Inc. J Appl

In the present study, CR-39 polymer of thickness 100 μm is irradiated with swift heavy ions of Li +3 (45 MeV), Ni +9 (120 MeV) and Au +9 (120 MeV) with ion fluence ranging from 10 10 ion/cm 2 to 10 12 ion/cm 2 . The effects of swift heavy ions on the structural, optical and surface properties of CR-39 are determined. The structural and surface properties are investigated using X-Ray diffraction (XRD) and Scanning Electron Microscopy (SEM), whereas the optical studies are carried out employing UV–vis spectroscopy. UV–vis spectroscopy shows that the band gap of the polymer decreases with ion fluence. The decrease in band gap is more significant in the case of Au beam as compared to Li beam. The FTIR spectrum shows reduction in intensity of typical modes, indicating the degradation of polymer after irradiation. The X-ray diffraction patterns show the amorphous nature of CR-39 polymer. The SEM studies show a systematic change in the surface morphology of the polymers with ion fluence.

The synthesis of nanostructured polypyrrole (Ppy) films by electrochemical process and their modifications by electronic excitations induced by swift heavy ion irradiations is reported in this paper. The electrical property of ion beam irradiated polypyrrole was investigated at low temperature by resistivity measurements. The structural and optical properties were also studied using X-ray diffraction (XRD), UV–vis spectroscopy and scanning electron microscopy (SEM). At low temperature, the polypyrrole films show the metallic behaviour after ion beam irradiation. UV–vis spectroscopy shows a red shift in the absorbance edge and thus reduction in band gap with increasing ion fluence. The structural studies show that the percentage crystallinity improves with increase in ion fluence. The SEM study corroborates the results of structural analysis and shows the formation of rod type structures along with the evolution of amorphous phase with increasing ion fluence.

Nanostructured polypyrrole films doped with para-toluene sulfonic acid were prepared by an electrochemical process, and a comparative study of the effects of swift heavy ions and γ-ray irradiation on the structural and optical properties of the polypyrrole was carried out. Oxygen-ion (energy = 100 MeV, charge state = +7) fluence varied from 1 × 1010 to 3 × 1012 ions/cm2, and the γ dose varied from 6.8 to 67 Gy. The polymer films were characterized by X-ray diffraction, ultraviolet–visible spectroscopy, and scanning electron microscopy. The X-ray diffraction pattern showed that after irradiation, the crystallinity improved with increasing fluence because of an increase in the crystalline regions dispersed in an amorphous phase. The ultraviolet–visible spectra showed a shift in the absorbance edge toward higher wavelengths, which indicated a significant decrease in the band gap of the polypyrrole film after irradiation. The scanning electron microscopy study showed a systematic change in the surface of the polymer. A similar pattern was observed with the γ irradiation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Electromagnetic duality has been utilized to study the isocolor charge-dyon interactions in Restricted Quantum Chromodynamics (RCD),in terms of current-current correlation (in magnetic gauge)using dielectric and permeability parameters of the associated vacuum. In the state of dyonic superconductivity, it has been shown that the dual propagators behave as 1/k4 (for small k2), which in analogy with superconductivity (dual superconductivity) leads to the confinement of colored fluxes associated with dyonic quarks vide generalized Meissner effect. Based on semi-quantitative analysis of vortex solutions of RCD and by calculating the masses for the massive collective modes of the condensed vacuum, the expressions for the London penetration depth, coherence length and the associated flux energy functions for the type I and type II superconducting media have been obtained. It has further been demonstrated that in the type I medium, vortices tend to coalesce and hence are attractive, while the energy function supports repulsive forces between vortices in the type II superconducting medium. The RCD has been supersymmetrized in N =1 limit and the supersymmetric dyonic solutions have been obtained. In the dyonic background gauge one-loop quantum corrections to the dyonic mass have been calculated and it has been shown that the one-loop quantum corrections lead no change in classical mass of the dyon.

High-energy ion beam irradiation of the polymers is a good technique to modify the properties such as electrical conductivity, structural behaviour and mechanial properties. Polyaniline thin films doped with hydrochloric acid (HCl) were prepared by oxidation of ammonium persulphate. The effect of Swift Heavy Ions irradiation on the electrical and structural properties of polyaniline has been measured in this study. Polyaniline films were irradiated by oxygen ions (energy 80 MeV, charge state O+7) with fluence varying from 1 × 1010 to 3 × 1012 ions/cm2. The studies on electrical and structural properties of the irradiated polymers were investigated by measuring V-I using four probe set-up and X-ray diffraction (XRD) using Bruker AXS, X-ray powder diffractometer. V-I measurements shows an increase in the conductivity of the film, XRD pattern of the polymer shows that the crystallinity improved after the irradiation with Swift Heavy Ions (SHI), which could be attributed to cross linking mechanism.

Commercially purchased CR-39 and PET polymers were irradiated by 100 MeV O7+ ions of varying fluences, ranging from 1×1011 to 1×1013 ions/cm2. The effects of swift heavy ions (SHI) on the structural, optical and chemical properties of CR-39 and PET polymers were studied using X-ray diffraction (XRD), UV–visible spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The XRD patterns of CR-39 show that the intensity of the peak decreases with increasing ion fluence, which indicates that the semicrystalline structure of polymer changes to amorphous with increasing fluences. The XRD patterns of PET show a slight increase in the intensity of the peaks, indicating an increase in the crystallinity. The UV–visible spectra show the shift in the absorbance edge towards the higher wavelength, indicating the change in band gap. Band gap in PET and CR-39 found to be decrease from 3.87 to 2.91 and 5.3–3.5 eV, respectively. The cluster size also shows a variation in the carbon atoms per cluster that varies from 42 to 96 in CR-39 and from 78 to 139 in PET. The FTIR spectra show an overall reduction in intensity of the typical bands, indicating the degradation of polymers after irradiation.

Conducting polypyrrole (PPY) polymer thin films, prepared by the electrochemical process, were irradiated with 50 MeV Li3+ and 90 MeV C6+ ions at different fluences, ranging from 1011 to 1014 ions cm−2. The structural and electrical properties of the swift heavy ions (SHI) irradiated films were analyzed using X-ray diffraction (XRD), Scanning electron microscope (SEM), and conductivity measurement methods. XRD analysis of SHI irradiated PPY films shows that the crystallinity of the PPY films increases with increasing fluences of lithium ions, but tends to become amorphous at higher fluence. Carbon ions irradiations lead to polymer destruction and simultaneous amorphization even at low fluence. The SEM studies of irradiated PPY films show systematic change in their surface morphologies. The surface was smoother at lower fluence but craters were observed at higher fluence. The surface conductivity of films increases with increasing fluence of lithium ions, which also turn to the virgin film conduct...

Using electromagnetic duality, the isocolor charge-dyon interactions were studied in restricted quantum chromodynamics (RCD) in terms of current-current correlations in the magnetic gauge using the dielectric and permeability parameters of the associated vacuum. The resulting 1/k4 behaviour of the dual propagators is interpreted as a signature of confinement for the corresponding colored fluxes of the theory. Evaluating the vortex solutions of RCD semi-quantitatively, in accordance with Higgs-Ginzburg-Landau theory, expressions for London penetration depth, coherence length, and associated flux energy functions for types I and II superconducting media are derived and an analogy of the type of superconducting medium with the bag model and string picture of hadrons is discussed.PACS Nos.: 11.30 Jw, 14.80 Hv, 12.38 Aw

A criterion is derived for the determination of parameter domains of first-order phase transitions in quantum-mechanical tunneling models. The criterion is tested by application to various models, in particular to some that have been used recently to explore spin tunneling in macroscopic particles. In each case agreement is found with previously heuristically determined domains.

The role of the Floquet parameter in the quantization of a particle in the field of two parallel string-like solenoids is clarified.

QCD as a dual gauge theory has been constructed in terms of restricted chromodynamics by using the magnetic symmetry. The associated dual structure has been utilized to explain the colour confinement as a result of dynamical breaking of magnetic symmetry and the parameters related to the confinement have been derived. The generalized supercurrent of dyonically condensed vacuum has been shown to lead to the generalized Meissner effect responsible for the confining nature of RCD vacuum. The range parameter analysis has been shown to unfavour the higher-order Dirac charges and it has been demonstrated that the generalized-charge-space parameter can improve the RCD confining properties.

Considering quarks as dyons, we analyze different possibilities for free fractional electric charges and monopoles to coexist. For nonvanishing vacuum angleθ, electric charges of dyons are not exactly fractional, but carry extra charges proportional toθ. The average extra charge vanishes for mesons, but not for baryons.

Some of the non‐relativistic quark model (NRQM) predictions of some spin and flavor parameters are in sharp conflict with the observations made from deep inelastic scattering experiments. Besides this there are other spin and flavor dependent quantities which could not be explained by NRQM. These contradictions are referred to as Proton spin problem. These issues get resolved, to some extent, in Chiral Constituent Quark Model ( CQM) which incorporates the basic features of NRQM and chiral symmetry. The implications of the latest data pertaining to ū−d asymmetry and the spin polarization functions on the contributions of singlet Goldstone Boson η′ within CQM with configuration mixing for explaining the proton spin problem have been investigated. It is found that the present data favors smaller values of the coupling of singlet Goldstone Boson as compared to the corresponding contributions from π, K and η′ Goldstone bosons. It seems that a small non‐zero value of the coupling of η′(ζ≠0)(ζ≠0) is preferred o...

Using the latest data pertaining to \bar u-\bar d asymmetry and the spin polarization functions, detailed implications of the possible values of the coupling strength of the singlet Goldstone boson \eta' have been investigated in the \chiCQM with configuration mixing. Using \Delta u, \Delta_3, \bar u-\bar d and \bar u/\bar d, the possible ranges of the coupling parameters a, \alpha^2 a, \beta^2 a and \zeta^2 a, representing respectively the probabilities of fluctuations to pions, K, \eta and \eta^{'}, are found. To further constrain the coupling strength of \eta', detailed fits have been obtained for spin polarization functions, quark distribution functions and baryon octet magnetic moments. The fits clearly establish that a small non-zero value of the coupling of \eta' is preferred over the higher values of $\eta'$ as well as when \zeta=0, the latter implying the absence of \eta' from the dynamics of \chiCQM. Our best fit achieves an overall excellent fit to the data, in particular for \Delta u, \Delta d, \Delta_8 as well as the magnetic moments \mu_{n}, \mu_{\Sigma^-}, \mu_{\Sigma^+} and \mu_{\Xi^-}. The implications of \eta' on the gluon polarization have also been investigated., Comment: 7 pages, 2 tables. Presented at the 17th International Spin Physics Symposium, Kyoto, Japan, October 2-7, 2006

Using the latest data pertaining to \bar u-\bar d asymmetry and the spin polarization functions, detailed implications of the possible values of the coupling strength of the singlet Goldstone boson \eta' have been investigated in the \chiCQM with configuration mixing. Using \Delta u, \Delta_3, \bar u-\bar d and \bar u/\bar d, the possible ranges of the coupling parameters a, \alpha^ 2, \beta^ 2 and \zeta^ 2, representing respectively the probabilities of fluctuations to pions, K, \eta and \eta^{'}, are shown to be 0.10 \lesssim a \lesssim 0.14, 0.2\lesssim \alpha \lesssim 0.5, 0.2\lesssim \beta \lesssim 0.7 and 0.10 lesssim |\zeta| \lesssim 0.70. To constrain the coupling strength of \eta', detailed fits have been obtained for spin polarization functions, quark distribution functions and baryon octet magnetic moments corresponding to the following sets of parameters: a=0.1, \alpha=0.4, \beta=0.7, |\zeta|=0.65 (Case I); a=0.1, \alpha=0.4, \beta=0.6, |\zeta|=0.70 (Case II); a=0.14, \alpha=0.4, \beta=0.2, \zeta=0 (Case III) and a=0.13, \alpha=\beta=0.45, |\zeta|=0.10 (Case IV). Case I represents the calculations where a is fixed to be 0.1, in accordance with earlier calculations, whereas other parameters are treated free and the Case IV represents our best fit. The fits clearly establish that a small non-zero value of the coupling of \eta' is preferred over the higher values of \eta' as well as when \zeta=0, the latter implying the absence of \eta' from the dynamics of \chiCQM. Our best fit achieves an overall excellent fit to the data, in particular the fit for \Delta u, \Delta d, \Delta_8 as well as the magnetic moments \mu_{n}, \mu_{\Sigma^-}, \mu_{\Sigma^+} and \mu_{\Xi^-} is almost perfect, the \mu_{\Xi^-} being a difficult case for most of the similar calculations., Comment: 8 RevTeX pages, 2 Tables, Revised version to appear in Int.J.Mod.Phys A

Polypyrrole thin films doped with para-toluene sulphonic acid were prepared by the electrochemical process. High-energy ion beam irradiation of the polymers is an effective technique to enhance the electrical conductivity, structural property and mechanical properties. So polypyrrole and allyl diglycol carbonate (CR-39 (DOP)) films were irradiated by oxygen ions (energy 100MeV, charge state O +7 ) with fluence varying from 1 × 10 10 to 1 × 10 13 ionscm −2 . The effects of swift heavy ions (SHI) on the structural, optical and surface properties of polypyrrole (Ppy) and CR-39 (DOP) polymers were studied in this work using x-ray diffraction (XRD), UV‐visible spectroscopy and scanning electron microscopy (SEM). XRD patterns of the pristine and irradiated polymer show that the crystallinity improved after the irradiation with SHI. At the low fluence, crystallinity was found to increase but at high fluence, it decreases which could be attributed to cross-linking and degradation mechanism. The UV‐visible spectra show a shift in the absorbance edge towards higher wavelength, which can be correlated with the transition involved in the polymer and variation in the band gap using Tauc’s expression. The band gap of polypyrrole was found to decrease from 3.4 to 3.0eV after irradiation. CR-39 (DOP), however, showed a very large change in the band gap from 4.8 to 3.4eV. The SEM study shows a systematic change in the surface morphology of the polymers with increasing ion fluence. (Some figures in this article are in colour only in the electronic version)

A self-consistent theory of dyons in Abelian and non-Abelian limits has been formulated in terms of an extra magnetic symmetry and topological magnetic charge. It has been shown that the restricted gauge potential describes the fields of dyons in terms of two regular (time-like) potentials only when recourse is made to the duality of topological (magnetic) and isocolour (electric) charges. Choosing a suitable Lagrangian density for the system of dyons in non-Abelian gauge theory, the field equations, energy-momentum tensor, Hamiltonian and momentum densities have also been derived and the conservation of the four-linear momentum and the total angular momentum has been demonstrated.

Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India in summer and winter to obtain the seasonal variation and its correlation with radon exhalation rate. The environmental surface gamma dose rate was also measured in the same area. The radon exhalation rate in the soil sample collected from different geological unit of Budhakedar area was measured using plastic track detector (LR-115 type II) technique. The variation in the radon concentration in soil-gas was found to vary from 1098 to 31,776 Bq.m−3 with an average of 7456 Bq.m−3 in summer season and 3501 to 42883 Bq.m−3 with an average of 17148 Bq.m−3 in winter season. In groundwater, it was found to vary from 8 to 3047 Bq.l−1 with an average value 510 Bq.l−1 in summer and 26 to 2311 Bq.l−1 with an average value 433 Bq.L−1 in winter. Surface gamma dose rate in the study area varied from 32.4 to 83.6 μR.h−1 with an overall mean of 58.7 μ-R.h−1 in summer and 34.6 to 79.3 μR.h−1 with an average value 58.2 μR.h−1 in winter. Radon exhalation rate from collected soil samples was found to vary from 0.1 × 10−5 to 5.7 × 10−5 Bq.kg−1.h−1 with an average of 1.5 × 10−5 Bq.kg−1.h−1 in summer season and 1.7 × 10−5 to 9.6 × 10−5 Bq.kg−1.h−1 with an average of 5.5 × 10−5 Bq.kg−1.h−1. A weak negative correlation was observed between radon exhalation rate from soil and radon concentration in the soil. Radon exhalation rate from the soil was also not found to be correlated with the gamma dose rate, while it shows a positive correlation with radon concentration in water in summer season. Inter-correlations among various parameters are discussed in detail.