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In this research work, nanocomposites of CuO/TiO₂ were initially fabricated using drop casting method. Later on, these nanocomposites were irradiated for the first time by a beam of Argon ions (Ar${}^{+})$ by keeping the fluence rates of $1\times 10^{14}$ ions cm${}^{-2}$, $1\times 10^{15}$ ions cm${}^{-2}$, and $1\times 10^{16}$ ions cm${}^{-2}$, respectively. In order to observe structural and optical properties of un-irradiated and irradiated nanocomposites, Raman Spectroscopy, Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Photoluminescence (PL) and Diffuse Reflectance Spectroscopy (DRS) analysis were performed. From Raman analysis, vibration modes confirmed the presence of different phases of TiO₂ and CuO. EDX analysis clearly demonstrates the presence of Cu, Ti, and O peaks. SEM images depict agglomerated spherical nanoparticles having diameters in the range of 40–94nm. From TEM analysis, mean diameter of 56.1nm is observed for unirradiated and 33.7nm for Ar${}^{+}$ irradiated CuO/TiO₂ nanoparticles in nanocomposite for fluence rates of $1\times 10^{14}$ ions cm${}^{-2}$, $1\times 10^{15}$ ions cm${}^{-2}$, and $1\times 10^{16}$ ions cm${}^{-2}$. HR-TEM and SAED images represent the polycrystalline nature of these nanocomposites.

Among the three peaks of PL spectra in UV–Visible region, first two peaks were observed at 356nm, and 419nm but the third peak is little shifted from 488nm with the increase in fluence rate. Values of band gap are reduced from 3.29eV to 3.17eV as the fluence rate is increased, as calculated from results of diffuse reflectance spectroscopy.

Alterations of heavy metal concentration in inoculated Sarcoma -180 after irradiation by 6MeV electron beam at the doses of 5Gy were evaluated in vivo in BALB/c mice, by Particle Induced X -ray Emission (PIXE).

Analysis was performed for K, Cl, S, Fe, Zn and Cu. In the irradiation of 5Gy, the concentration of K and Cl have revealed the fast incremment at 1 hour after irradiattion and the fast decremment after that time. As for the S, Fe, Cu and Zn, their concentrations have revealed the fast incremment at 1 hour after irradiattion and the slow decremment from 1 hour after irradiation (except for slow increment from 1 hour to 1 day after).

Physiological activity of irradiated green tea polyphenol on the human skin was investigated for further industrial application. The green tea polyphenol was separated and irradiated at 40 kGy by γ-ray. For an anti-wrinkle effect, the collagenase inhibition effect was higher in the irradiated sample (65.3%) than that of the non-irradiated control (56.8%) at 200 ppm of the concentration (p < 0.05). Collagen biosynthesis rats using a human fibroblast were 19.4% and 16.3% in the irradiated and the non-irradiated polyphenols, respectively. The tyrosinase inhibition effect, which is related to the skin-whitening effect, showed a 45.2% and 42.9% in the irradiated and the non-irradiated polyphenols, respectively, at a 100 ppm level. A higher than 90% growth inhibition on skin cancer cells (SK-MEL-2 and G361) was demonstrated in both the irradiated and the non-irradiated polyphenols. Thus, the irradiation of green tea polyphenol did not change and even increased its anti-wrinkle, skin-whitening and anticancer effects on the human skin. The results indicated that irradiated green tea polyphenol can be used as a natural ingredient with excellent physiological functions for the human skin through cosmetic or food composition.

In our studies we observed a self-doping effect in Bi 2212 epitaxial thin films, totally covered by a protective golden layer, after the irradiation of these films with heavy ions. The irradiation with heavy ions was made in order to create columnar defects in the samples. We studied Bi 2212 thin films having various oxygen contents before irradiation and we observed for all of them an increase of the oxygen content in the films due to this self-doping effect caused by irradiation.

Stress relaxation rate in unirradiated and electron-beam-irradiated polycrystalline titanium (99.994%) was studied in the temperature range 300–100 K. Titanium specimens were irradiated with 12 MeV electrons to a dose of 0.01 dpa for 12 min. at 300 K. Tensile tests of the specimens were performed using a Universal Testing Machine in the given temperature range. To measure the relaxation of stress with time, the crosshead of the machine was arrested at different fixed loads. Stress relaxation rate s for a given stress level σ₀ was found to be temperature dependent, i.e., it decreased with decreasing temperature both in unirradiated and irradiated specimens. However, the decrease was more pronounced in irradiated specimens than that of unirradiated ones. The observed decrease in s values with decrease in temperature is ascribed to the retarding effect of unrelaxed dislocations pinned at defects, especially at the twin boundaries in the course of deformation, which became more conspicuous in irradiated specimens due to the interaction of glide dislocations with radiation-induced defects, in addition to mechanical twins. The activation energy for the movement of dislocations, calculated using the single-barrier model of stress relaxation, was found to be higher in irradiated specimens than that of unirradiated ones at all test temperatures.

Two sets of amorphous carbon materials prepared at different routes are irradiated with swift (145 MeV) heavy ion (Ne⁶⁺). The structural parameters like the extent of local ordering along the c and a axis i.e., L_c and L_a, the average spacing of the crystallographic planes (002) i.e., d₀₀₂ and the fraction of the amorphous phase of the unirradiated and the irradiated samples are estimated by X-ray diffraction technique. The fraction of the amorphous phase is generally found to increase with the irradiation dose for both sets of the samples. The estimated d₀₀₂ values are found to be almost unaffected by irradiation but L_c and L_a are decreased slightly with irradiation. The estimated values of L_c and L_a corroborate with the increase of disorder in both sets of the samples with the increasing dose of irradiation.

Fluorinated graphene was irradiated by electron beam, and the changing of fluorinated graphene after electron beam irradiation was found by several detection techniques of Raman, electrical characterization and X-ray photoelectron spectroscopy (XPS). Raman spectra and electric characterization confirmed that the crystal structure and electrical performance of graphene was recovered partially after electron beam irradiation. XPS results indicated that the concentration of fluorine quickly dropped from 35% to 15% just after 30 min irradiation, and then dropped, slowly to 10% with the irradiation time to 150 min. The results indicate that stimulate fluorine desorption from fluorinated graphene used electron beam completely is difficult, which means a big challenge for ESD to fabricate all graphene electronics.

Extruded samples of ${\mathrm{\text{Bi}}}_{85}{\mathrm{\text{Sb}}}_{15}$ solid solutions doped with 0.0005 at.% Te were obtained and the electrical conductivity $(\sigma )$, thermoelectric power (Seebeck) $(\alpha )$, Hall $(R_h)$ and thermal conductivity $(\chi )$ coefficients were investigated in the range $\sim 80$–300 K samples and magnetic field strength up to $74\times 10^4$ A/m, as annealed after extrusion, non-irradiated with gamma-quanta and the same samples irradiated with gamma quanta at different doses. It was found that at low doses (1 Mrad) of irradiation, radiation defects (RDs) appear in the samples which play the role of donor centers, as a result of which the concentration of free electrons $n$, and, consequently the electrical conductivity $\sigma$ increases, and the Seebeck coefficient $\alpha$ decreases. These defects, scattering the current carriers, reduce their mobility $\mu$. With an increase in the radiation dose, the concentration of defects also increases and free carriers are captured at the level of the RD. In this regard, the concentration of charged carrier defects $n$ and, consequently, $\sigma$ of the sample decrease, while the Seebeck coefficient and mobility increase. The effect of a magnetic field on the electrical and thermal parameters of extruded solid solution samples also depends on the radiation dose in the sample.

Derived through liquid phase exfoliation, the irradiation response of nanoscale, exfoliated tin sulfide (SnS) systems are being reported in this work. The SnS nanosheets were exposed to 90MeV ${\text{C}}^{6+}$ ion beams across fluences ranging from $1\times 10^{10}$ to $1\times 10^{13}$ions/cm². With an electronic energy loss ($S_e$) of $\sim$56eV/Å, dominating over the nuclear energy loss ($S_n$), the average crystallite size of the irradiated samples displayed an augment when compared to its pristine counterpart. Exhibiting an orthorhombic crystal structure, structural analyses of both pristine and irradiated samples were conducted via X-ray diffraction (XRD) technique. Raman analysis has manifested some modifications in the SnS nanosystem upon radiation exposure, particularly with higher fluences causing local structural disorder and amorphization of the material. Moreover, morphological changes in the irradiated SnS samples were examined using field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM), with AFM images revealing an increase in the root mean square (RMS) roughness corresponding to ion fluence. Furthermore, swift heavy ion (SHI) irradiation prompted a non-rectifying Ohmic $I\sim V$ characteristics and altered the electrical conductivity of the SnS nanosheets.

Stress relaxation rate in un-irradiated and neutron-irradiated 303 stainless steel was investigated at room temperature. The specimens were exposed to 100 mC, Ra-Be neutron source of continuous energy 2–12 MeV for a period ranging from 4 to 16 days. The tensile deformation of the specimens was carried out using a Universal Testing Machine at 300 K. During the deformation, straining was frequently interrupted by arresting the cross head to observe stress relaxation at fixed load. Stress relaxation rate, s, was found to be stress dependent i.e. it increased with increasing stress levels σ₀ both in un-irradiated and irradiated specimens, however the rate was lower in irradiated specimens than those of un-irradiated ones. A further decrease in s was observed with increase in exposure time. The experiential decrease in the relaxation rate in irradiated specimens is ascribed to strong interaction of glide dislocations with radiation induced defects. The activation energy for the movement of dislocations was found to be higher in irradiated specimens as compared with the un-irradiated ones.

XANES measurements at the Fe-K edge on natural South African sapphire single crystal (corundum) and an irradiated sample with fluence 1 × 10¹²Ni⁶⁺ions/cm² are reported. Some decrease in intensity of pre-edge features (1s → 3d) and increase in intensity of 1s → 4p transition in Fe is observed with Ni fluence. Structural changes and modification on surface of irradiated sapphire with Ni⁶⁺ ion have been observed by the atomic force microscopy technique and discussed in the term of defects.

The present study reports the stress relaxation behavior of irradiated polycrystalline 5N copper deformed in the temperature range 150 to 300 K. The wire specimens were exposed to an 18 MeV electron beam at room temperature and stress relaxation tests of the specimens were carried out during the tensile test, using universal testing machine between 150 to 300 K. Stress relaxation rate of the specimens was found to decrease with the decrease of test temperature. The decrease of the stress relaxation rate with temperature in irradiated specimens is attributed to the dislocation-defects interaction, which is more pronounced at low temperature due to the reduction in available thermal energy necessary for the relaxation of dislocations.

In this work, modification in structural and electrical properties of zirconium nitride (ZrN) thin films induced by silicon-ion irradiation is studied. ZrN thin films are grown on glass substrate over Zirconium (Zr) layer using cathodic arc evaporation method. The samples of the film are irradiated with silicon ions of energy 2.08 MeV at different fluences ranging from $5\times 10^{13}$ ions/cm${}^{-2}$ to $5\times 10^{15}$ ions/cm${}^{-2}$. The structural and electrical properties of the prepared films are investigated using X-ray diffraction (XRD), Raman spectroscopy and four-point probe method. XRD analysis shows significant shift in the peak corresponding to (111) crystallographic plane of ZrN at low fluence ($5\times 10^{13}$ ions/cm${}^{-2}$) while modest peak shift at high fluence rate ($5\times 10^{15}$ ions/cm${}^{-2}$) is observed. Under the electrical properties point of view, it is observed that the decrease in resistivity is small at high ion fluence as compared to that at low ion fluence. At highest fluence of $5\times 10^{15}$ ions/cm${}^{-2}$, resistivity of the irradiated sample approaches the resistivity of the un-irradiated sample indicating very small changes in structure at very high dose irradiance.

In this paper, the effects of successively applied static/pulsed negative bias temperature (NBT) stress and irradiation on commercial p-channel power vertical double-diffused metal-oxide semiconductor (VDMOS) transistors are investigated. To further illustrate the impacts of these stresses on the power devices, the relative contributions of gate oxide charge ($N_{\mathrm{\text{ot}}}$) and interface traps ($N_{\mathrm{\text{it}}}$) to threshold voltage shifts are shown and studied. It was shown that when irradiation without gate voltage is used, the duration of the pre-irradiation static NBT stress has a slightly larger effect on the radiation response of power VDMOS transistors. Regarding the fact that the investigated components are more likely to function in the dynamic mode than the static mode in practice, additional analysis was focused on the results obtained during the pulsed NBT stress after irradiation. For the components subjected to the pulsed NBT stress after the irradiation, the effects of $N_{\mathrm{\text{ot}}}$ neutralization and $N_{\mathrm{\text{it}}}$ passivation (usually related to annealing) are more enhanced than the components subjected to the static NBT stress, because only a high temperature is applied during the pulse-off state. It was observed that in devices previously irradiated with gate voltage applied, the decrease of threshold voltage shift is significantly greater during the pulsed NBT stress than during the static NBT stress.

The p-silicon surfaces have been irradiated with ~ 100 MeV Si⁷⁺ions to a fluence of 2.2×10¹³ ions cm^-2, and surface morphology has been studied with atomic force microscopy (AFM). Interesting features of cracks of ~ 47 nm in depth and ~ 103 nm in width on the irradiated surfaces have been observed. The observed features seemed to have been caused by the irradiation-induced stress in the irradiated regions of the target surface.

The microstructural modifications due to high energy electrons (8–18 MeV) and their correlation with the yielding behavior of polycrystalline nickel have been investigated. The specimens in the form of strips were irradiated at room temperature for 15 min in the energy range 8–18 MeV using linear accelerator. The comparison of microstructural results of irradiated specimens with that of the un-irradiated ones reveals that radiation deteriorate the surface of the target specimens. The damage was found to be more prominent at the grain boundaries. The tensile tests of both unirradiated and irradiated samples were carried out using Universal Testing Machine at room temperature. An increase in yield stress and loss of ductility was observed in case of irradiated specimens, which became more pronounced with an increase of incident beam energy. These effects are attributed to the interaction of glide dislocations stress fields with the defects produced during irradiation.

This paper reports on the electron scattering, charge transport and charge trapping of a polymer subjected to intermediate-energy electron beam in a self-consist charging model. Numerical simulation of a charging balance is performed using incident intermediate-energy electron current and leakage current, and the space charging characteristics are examined. The mechanisms involve various microscopic parameters that are related to the space potential and the characteristics of the polymer as well as to the effects of the space charge, electron charge, hole charge and trapped charge itself. The dynamic transporting and trapping properties of a polymer are investigated, and the space potential is evaluated using various parameters of irradiation. Trapping of electrons is determined using Poole–Frenkel trapping–detrapping mechanisms. Various types of space charging behavior are observed by controlling irradiation conditions. Furthermore, the peak location of space charge is simulated and validated by Sessler's experimental data in microscopic perspective.

The thermal and mechanical properties of nasopharyngeal airway (NPA) samples are improved by irradiation using 4keV oxygen and nitrogen ion beams with different ion fluences varying from $25\times 10^{17}$ ions/cm² to $65\times 10^{17}$ ions/cm². The thermal stability of NPA medical device increases with increasing nitrogen and oxygen ion fluences. The tensile strength increased from 48MPa for unirradiated sample to 74MPa for samples irradiated with nitrogen and to 58MPa for samples irradiated with oxygen ion, while the elongation at break decreases for irradiated samples. Silver thin films are deposited on NPA medical device samples using 4keV argon ion beam. The XRD spectra demonstrated that silver nanoparticles are deposited on NPA medical device substrate. The effects of Ag thin film on gram-positive and gram-negative bacteria are studied.

In this paper, formation of defects/defect clusters in nickel nanowires (Ni-NWs) due to interaction of a 60 kilo-electron-volt (keV) beam of proton (H${}^{+})$ ions is studied. Ni-NWs are exposed to various fluencies of H${}^{+}$ ions ranging between $1.5\times 10^{15}$ and $1.5\times 10^{17}$ions/cm². The analysis of pristine and H${}^{+}$ ion-irradiated Ni-NWs samples is mainly done using transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. Stopping range of ions in matter (SRIM) simulation software is employed to verify the production of defect clusters in Ni-NWs theoretically. Furthermore, insight of creation of defects in Ni-NWs due to interaction of low energy H${}^{+}$ ions in keV range is made using the theory of collision cascade effect. The study of defect clusters induced in Ni-NWs under H${}^{+}$ ions beam irradiation is essential for application of Ni-NW-based nanodevices in harsh environment containing plenty of H${}^{+}$ ions such as for use in spacecraft equipped for space missions.

In this paper, we report the influence of low-energy oxygen ion irradiation with fluence ranging from $0.5\times 10^{17}$$\text{ions}\cdot {\text{cm}}^{-2}$ to $1.5\times 10^{17}$$\text{ions}\cdot {\text{cm}}^{-2}$ on the structural, optical, and electrical properties of fresh and annealed (400^∘C, 3h) zinc oxide (ZnO) thin films. These films were grown on soda-lime glass (SLG) substrates using the spin-coating method as a low-cost depositing technique. X-ray diffraction (XRD) study showed the formation of the hexagonal phase of ZnO thin films with preferred orientation along the (002) plane. The crystallite size for fresh and annealed ZnO thin films was in nanoscale and it increased with the annealing temperature. Also, the crystallite size increased with the ion beam irradiation fluence in the case of annealed ZnO films, while it slightly decreased for the fresh ZnO films. The transmittance and absorbance spectra for the ZnO films were investigated in a wide wavelength range. The optical bandgap was specified by using Tauc’s relation. The electrical properties of the ZnO films (fresh and annealed at 400^∘C for 3h) were studied before and after the oxygen ion beam irradiation. Also, the dielectric properties were investigated with respect to frequency at different ion beam irradiation fluences. The comprehensive results showed the dielectric and optical properties are improved due to the induced conductive networks by oxygen ion irradiation.