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In this work, the surface properties of Mg–Al–Zn (AZ91D) alloy such as surface morphology, hardness and electrochemical corrosion were studied after copper ions (Cu${}^{+})$ irradiation at different energies (0.8, 1.5, 2.5 and 3.5MeV) while keeping the ion dose constant at $5\times 10^{14}$ ions/cm². The morphological features of irradiated samples showed defects composed of ejected material from the alloy surface that became more significant at 3.5MeV. The Vickers hardness was increased with increase of the Cu${}^{+}$ energy. The electrochemical testing of the samples was conducted in a Ringer Lactate solution. The potentiodynamic polarization results revealed anomalous changes in the corrosion rate of the Mg alloy with increase of the Cu${}^{+}$ energy. The corrosion rate was considerably decreased with increase of the Cu${}^{+}$ energy to 3.5MeV. These changes were associated with the surface defects and passive film formation on the alloy surface.

In the present research, cellulose acetate (CA) and polyaniline (PANI) were combined to form CA/PANI films using the solution-casting method. This research aims to provide novel optical behavior for irradiated flexible CA/PANI sheets to be utilized in high-performing optical devices. The Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM) were employed to effectively produce the CA/PANI samples. The argon fluence of $2\times 10^{17}$, $4\times 10^{17}$, and $6\times 10^{17}$ions/cm² have been added to these films. The FTIR and XRD measurements showed that the ion treatment of CA/PANI films altered their functions and crystalline compositions. This indicates that the CA/PANI films were successfully prepared. The optical properties were measured using the UV–Vis technique in a wavelength of 200–1150nm. The Tauc relationship was used to estimate the band gap and Urbach energies of both bombarded and untreated films. In response to $2\times 10^{17}$, $4\times 10^{17}$, and $6\times 10^{17}$ions/cm², CA/PANI exhibits a drop in band gap from 4.92eV to 4.45, 4.31, and 4.20eV, respectively. According to these results, the optical performance of the irradiated CA/PANI composite films was modified to be used in optoelectronics.

Influence of Ni¹¹⁺ swift heavy ion (SHI) irradiation induced modifications on structural and morphological aspects of CuFe₂O₄ nanoparticles have been studied. The bulk sample is synthesized using co-precipitation technique. The cubic spinel structure is identified using X-ray diffraction technique and these nanoparticles have an average grain size of about 10 nm. These materials are irradiated at various fluences of 1 × 10¹¹, 1 × 10¹², 1 × 10¹³, 1 × 10¹⁴, and 5 × 10¹⁴ions/cm² using Ni¹¹⁺ ion beam of 150 MeV energy. The XRD pattern of the irradiated material shows the change in crystalline nature. The spinel ferrite (311) peak, which is having maximum intensity in the pristine, decreases at the fluence of 1 × 10¹¹ and 1 × 10¹²ions/cm² and then completely vanishes on further irradiation. However, a new X-ray peak arises in the (222) direction. All the other peaks in the pristine sample vanish on irradiation elucidating the creation of amorphization nature. Scanning electron microscope (SEM) analysis shows fine blocks of material for pristine and partial agglomeration on irradiation. Notably, a large number of holes are present at the fluence of 5 × 10¹⁴ions/cm² due to heavy ion irradiation. The phase change from crystalline to amorphous nature on XRD and the creation of holes from SEM is discussed on the basis of electrophonon coupling and it invokes the thermal spike theory.

Here we report the role of ion irradiation in the field emission characteristics of aligned multiwalled carbon nanotubes (MWNTs). Aligned MWNTs show improvement in field emission characteristics under low dose 70 Mev Ni⁶⁺ ion irradiation. But field emission current density reduces for the higher dose due to adsorption of amorphous carbon and melting as well damage of carbon nanotubes (CNTs). High resolution transmission electron microscopic (HRTEM) analysis has been carried out to find the morphological changes due to ion irradiation leading to modifications in field emission characteristics. At low dose formation of dangling bond, cross-linking between different layers, exposure of buried emission sites and reduction of mutual shielding are responsible for the enhancement in field emission characteristics.

Effect of irradiation on graphene oxide by sunlight, UV light and KrF excimer laser has been investigated in detail. Both sunlight and ultraviolet light reduce graphene oxide well after prolonged irradiation, but laser irradiation produces graphene with negligible oxygen functionalities within a short time. Laser irradiation is also useful for one-step synthesis of metal particle decorated graphene. Laser irradiation of graphene oxide appears to be an efficient procedure for large-scale synthesis of graphene.

70 MeV Si ions irradiation at the liquid nitrogen temperature (77 K) induced nanoclustering on GaN epilayers grown by Metal Organic Chemical Vapor Deposition (MOCVD) are reported. HRXRD rocking curves show that there are no localized amorphization due to irradiation. Atomic force microscopy images reveal the formation of nanoclusters on the surface of the irradiated samples. On increasing the fluence the number of modified regions on the surface increases and resulted in three dimensional growth of nanocluster due to overlapping and coalescence. X-ray photoelectron spectroscopy (XPS) studies confirm that the surface features are composed of GaN. The variation of carrier concentration and hall mobility with respect to ion fluence are also studied. The effects of ion-beam induced modifications on the structural, surface characteristics and electrical properties of GaN are studied and possible mechanisms responsible for the modifications are discussed.

Heterogenous photocatalysis is one of the promising methods of degradation of organic pollutants in the environment. This study developed a suitable and efficient method for photocatalytic degradation of Lambda-cyhalothrin LCY pesticide using Ce–ZnO nanocomposites under natural solar irradiation. Ce–ZnO was synthesized using the coprecipitation method and was ascertained through structural characterization. The crystal structure and crystallite size, surface morphology, functional groups present, and the elemental composition of the synthesized nanocomposites were determined by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and energy dispersive X-ray spectroscopy (EDAX), respectively. The average crystallite size of the nanocomposites was found to be 31.42 nm. The photocatalytic degradation of LCY was conducted in batches to obtain and determine the optimal conditions for the degradation of the pesticide. It was found that at optimum conditions; 100 ppm LCY initial concentration, 20 mg dose of the photocatalyst, and 10–11 UV index, Ce–ZnO were found to degrade about 92% of the initial concentration of LCY after 3 h of exposure to solar irradiation. It was found that Ce–ZnO possesses high photocatalytic activity against LCY and the kinetic of the degradation was found to fit the pseudo-first-order kinetic model.

A new kind of binary hydrogels composed of poly(dimethylaminoethylmethacrylate) (PDMAEMA) and poly(ethylene oxide) (PEO) with varying weight average molecular weights (, 1 × 10⁵ and 2.5 × 10⁶) were prepared by γ-irradiation technology. The properties of PDMAEMA/PEO hydrogels obtained were evaluated in terms of gel fraction, gel strength, thermal characterization and swelling behavior. The gel strength and swelling degree of the hydrogels could be improved obviously after adding PEO into the PDMAEMA system, while the degree of improvement decreased with increasing of PEO. The temperature sensitivity of PDMAEMA/PEO was retained only in the sample with PEO of , and the pH sensitivity was retained in samples with PEO of and 1 × 10⁵. When DMAEMA/PEO mixtures containing PEO of were irradiated, the main reaction could be the cross-linking of DMAEMA, and the linear PEO molecular chains could penetrate into the cross-linked network of PDMAEMA. With increasing of PEO, some side reactions were induced, such as grafting of DMAEMA onto PEO molecules, the scission or cross-linking of PEO.

Natural rubber latex (NRL) and methyl methacrylate (MMA) grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from Co-60 source at room temperature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy. Modulus increases from 6.99 MPa to 9.87 MPa for an increase in proportion of MMA grafted rubber from 40% to 60% in the blend at similar absorbed dose. Elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA grafted rubber content in the blends. The decreasing trend of permanent set is high up to 5 kGy absorbed dose, and beyond that dose it becomes almost flat.

Two different photocaged 2-nitrobenzyl-BODIPY derivatives were designed and synthesized, where the 2-nitrobenzyl phototrigger is either directly attached to the meso position of BODIPY or through a phenoxy linker. The photochemical and photophysical properties of the two constructs were studied and their fluorescence quantum yields were determined. The ultraviolet irradiation of the two photocaged BODIPYs demonstrated a twofold fluorescence enhancement accompanying the uncaging of the BODIPY with the directly attached phototrigger, while the second switchable dyad with the phenoxy linker retains its essentially unaltered emissive behavior.

Different time-dependent mechanisms such as creep, environmental surface oxidation or internal material degradation due to aging and irradiation will subject structures to the possibility of premature failures. In this paper a micro-scale finite element mesh consisting of multiple elements encased in ~50–150μm sized grains with designated grain boundaries is used to replicate shapes and dimensions to simulate an isotropic metallic microstructure. The grains are encased in pseudo-grain boundary element sets which can have different material and damage parameters compared to the grains. In this type of mesh random crack paths for intergranular and transgranular cracking conditions are allowed. It is shown that creep cracking using a uniaxial ductility constraint-based model coupled with a functionally distributed time-dependent environmentally assisted corrosion/oxidation/material degradation damage model acting on surface or internally can be realistically predicted using this model. It is also evident material properties input data have scatter especially at the sub-grain level where the measurement methods are new and not always standardised. This is dealt with in the model by employing a normal distributive probabilistic method to allow for statistically varied random damage and crack growth development. In this way it is possible to take into account the inherent variability in material input properties at the analysis stage without the need to change material properties following each run. The method could negate the need for knowing the exact material properties, which in any case is impossible to derive at the microstructural level, as results of each run can be varied using a statistically distributed critical damage criterion specified for each element.

Particle accelerators were initially developed to address specific scientific research goals, yet they were used for practical applications, particularly medical applications, within a few years of their invention. The cyclotron's potential for producing beams for cancer therapy and medical radioisotope production was realized with the early Lawrence cyclotrons and has continued with their more technically advanced successors — synchrocyclotrons, sector-focused cyclotrons and superconducting cyclotrons. While a variety of other accelerator technologies were developed to achieve today's high energy particles, this article will chronicle the development of one type of accelerator — the cyclotron, and its medical applications. These medical and industrial applications eventually led to the commercial manufacture of both small and large cyclotrons and facilities specifically designed for applications other than scientific research.

Medical applications represent the vast majority of the uses for radiotracers. This review addresses how accelerators are employed for the production of high purity radionuclides that are used in basic biomedical research, as well as for clinical medicine both for diagnosing disease and for treatment.

BeamCal is an electromagnetic sampling calorimeter in the very forward region of the detectors at the ILC. BeamCal will be hit by a large fraction of electron-positron pairs stemming from beamstrahlung. The sensors used for BeamCal have to withstand very high levels of total ionizing dose. We report on the investigations of radiation hard sensor materials for BeamCal of the FCAL collaboration. Artificial diamond, radiation hard silicon, SiC and GaAs sensors are under consideration. Static measurements of the current-voltage characteristics, response to minimum ionizing particles and test beam measurements are part of our investigations.

Medical applications represent the vast majority of the uses for radiotracers. This review addresses how accelerators are employed for the production of high purity radionuclides that are used in basic biomedical research, as well as for clinical medicine both for diagnosing disease and for treatment.

Particle accelerators were initially developed to address specific scientific research goals, yet they were used for practical applications, particularly medical applications, within a few years of their invention. The cyclotron's potential for producing beams for cancer therapy and medical radioisotope production was realized with the early Lawrence cyclotrons and has continued with their more technically advanced successors — synchrocyclotrons, sector-focused cyclotrons and superconducting cyclotrons. While a variety of other accelerator technologies were developed to achieve today's high energy particles, this article will chronicle the development of one type of accelerator — the cyclotron, and its medical applications. These medical and industrial applications eventually led to the commercial manufacture of both small and large cyclotrons and facilities specifically designed for applications other than scientific research.

The aim of this study is evaluate the fungal contamination in oolong tea irradiated with different radiation doses and water activities (Aw). Samples were irradiated in 60Co irradiator at doses of 0, 2.5, 5.0, 7.5 and 10.0kGy with three different water activities. In the sample with decreased water activity, the count of fungi was lower than others samples followed by original Aw and the samples with the higher Aw, however there is no difference between the increased and decreased water activities samples after the irradiation on fungi contamination at dose of 2.5kGy.

Microbiological contamination of coffee (Coffea arabica L.) is a problem in the industry, as coffee is especially sensitive to contamination. The occurrence of fungi and bacteria causes modification in the color and flavor, also loss of weight and the development of secondary metabolites. Irradiation is a decontamination method used for a variety of foodstuffs, being very feasible, effective and environment friendly without any significant change of sensory properties of the coffee. The aim of this study was to verify the effect of different gamma irradiation doses (0; 1, 5 and 3kGy to control bacteria and 0; 3; 6 and 9kGy to control fungi) on green coffee grains to determine if the microbiological load which is often present in coffee was destroyed. The results shows that microbiological contamination of coffee decrease when increase radiation doses.

The clove (Syzygium aromaticum) from the "Spice Islands" or Moluscas, Maluku Indonesian province. The clove portion used in the industry is the dried bud flower, leaf and stem. The clove has properties anti-irritant, soothing, relief of symptoms associated with motion sickness, nausea and vomiting. The clove essential oil is a phenolic compound from leaves and flowers (including stems) obtained from distillation. When extracted by steam distillation, high Eugenol rates, an aromatic compound is founded. The high eugenol content in essential oil can provide antimicrobial, antiseptic, bactericides, fungicides and fungicidal. The clove also acts as a food preservative due the high eugenol and tannins content. The oil is also used in flatulent colic treatment and some dental procedures. In food alimentation is used as a natural flavoring or added in small quantities and still has important applications in perfumery and cosmetics. Spices irradiation is a worldwide process used and this technique is an effective pathogenic microorganisms control providing consumers food security. By the fact cloves not only be used in food, but also as essential oil, this study intents to investigated the different irradiation doses influence on the possible antimicrobial potential of cloves oil and to evaluate the antifungal potential oil from unirradiated and irradiated clove in the fungus Guignardia citricarpa that causes serious damage in orange plantations. The clove samples were irradiated in ⁶⁰Co irradiator (Gammacell 220, Nordion Ltd., Canada) at doses of 0; 2.5; 5.0; 7.5 and 10.0kGy. The essential oils can demonstrate antifungal properties. The literature has recorded the extracts efficiency from a wide range of plant species to promote inhibition of several fungal phytopathogens. The clove essential oil showed a possible antifungal effect against the fungus Guignardia citricarpa