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This study investigated the feasibility of using deuterated titanium targets for the generation of a target normal sheath acceleration (TNSA) deuteron beam. Commercial 25- μ m-thick titanium foil was cut into 500 × 500- μ m2 squares and subsequently deuterated using different approaches. The spectra and total yields of all emitted ions were measured using a Thomson parabola ion spectrometer. It was found that a 24-h exposure to 1 atm of D 2 gas at 400 °C is the most-efficient deuteration method, producing yields in the mid-1011 deuterons per shot. The deuteron energy spectra changed from an exponential shape at low ion yields to exponentially modified Gaussians at higher yields. Simulations suggest that this effect is due to increased Coulomb interactions between the ions, which suppress the low energies. Separate campaigns will utilize the presented approach to produce a TNSA triton beam. Two such targets will be used in a pitcher/catcher configuration to study the tritium–tritium reaction T(t, 2n)α. [ABSTRACT FROM AUTHOR]

Abstract—The problem of heat distribution in metal materials irradiated by finely focused low-energy electron beams in the absence of heat exchange between the target and the surrounding environment is studied using mathematical modeling methods. The model is based on solving a multidimensional stationary heat equation using Green's function. The source function is a model applicable to a wide class of solids and primary-electron energy ranges, based on separation description of the absorbed and backscattered electron contributions to the energy dissipated in the target. The features of this approach explain the nonmonotonic dependence of the maximum heating temperature of the target on the primary-electron energy. [ABSTRACT FROM AUTHOR]

• The ballistic limit velocities of FSPs perforating plates of metallic alloys are examined. • We show that the failure properties of the plate material play a major role in this FSP/plate intercalation. • We find that the ballistic limits of FSPs impacting various aluminum alloys are practically insensitive to the alloy's strength. In a recent article Schonberg and Ryan (2021) reviewed nine analytical models from various sources, and examined their ability to predict the experimental ballistic limit velocities (V bl) of various metallic plates impacted by fragment simulating projectiles (FSP). These models analyzed the complex FSP/plate interaction, through simplified force equilibrium or energy conservation considerations. Schonberg and Ryan (2021) found that these models can predict the ballistic limit velocities to within ± 50% for more than 50% of the data base entries. On the other hand, they point out that "these models do not include the ductility and toughness properties of the materials involved", referring to the oversimplifications made in these models. The predicted V 50 values were given in these models in terms of the plate's properties (strength, density and thickness), as well as the density and dimensions of the projectile. In particular, these models result in monotonic expressions between the predicted V nl values and the corresponding strengths of the plates. The purpose of our comment is to demonstrate that, in fact, the test data in many cases do not follow this prediction. [ABSTRACT FROM AUTHOR]

Ba(ZrxTi1-x)O3(BZT) thin films with different Zr contents were deposited on (100)MgO and (100)Pt/(100)MgO substrates by RF-magnetron sputtering using metal targets. The BZT thin films had a single perovskite phase with only (001)/(100) orientation. In all cases, the ratio of Ba/Ti was stoichiometry and BZT films possess a dense microstructure. The grain size was decreased and BZT thin films showed ferroelectric-to-paraelectric properties with increasing Zr content. At room temperature, the tunability of nearly 30% was achieved at 1 MHz; meanwhile, a relatively low dielectric loss was obtained. These results indicated that we succeeded in depositing high-quality and potential tunable ferroelectrics. [ABSTRACT FROM AUTHOR]

Titanium dioxide (titania) is widely used as a photocatalyst for its moderate band gap, high photoactivity, recyclability, nontoxicity, low cost and its significant chemical stability. The anatase phase of titania is known to show the highest photocatalytic activity, however, the presence of this phase alone is not sufficient for sustained activity. In this study TiO2 coatings were deposited onto glass substrates by mid-frequency pulsed magnetron sputtering from metallic targets in reactive mode using a Full Face Erosion (FFE) magnetron, which allows the magnetic field to be modulated during the deposition process. The as-deposited coatings were analysed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and micro-Raman spectroscopy. Selected coatings were then annealed at temperatures in the range of 400-700 °C and re-analysed. The photocatalytic activity of the coatings was investigated through measurements of the degradation of organic dyes, such as methyl orange, under the influence of UV and fluorescent light sources. It has been demonstrated that, after annealing, the pulsed magnetron sputtering process produced photo-active surfaces and that the activity of the coatings under exposure to fluorescent lamps was some 35%-45% of that observed under exposure to UV lamps. [ABSTRACT FROM AUTHOR]

Monte Carlo calculations have been performed using MCNP code to study the optimization of photo-neutron yield for different electron beam energies impinging on Pb, W and Ta cylindrical targets of varying thickness. It is noticed that photo-neutron yield can be increased for electron beam energies ≥100 MeV for appropriate thickness of the target. It is also noticed that it can be maximized by further increasing the thickness of the target. Further, at higher electron beam energy heat gradient in the target decreases, which facilitates easier heat removal from the target. This can help in developing a photo-neutron source based on electron LINAC by choosing appropriate electron beam energy and target thickness to optimize the neutron flux for ADS, transmutation studies and as high energy neutron source etc. Photo-neutron yield for different targets, optimum target thickness and photo-neutron energy spectrum and heat deposition by electron beam for different incident energy is presented. [ABSTRACT FROM AUTHOR]

The stopping power of an impinging electron beam depends on the atomic number and the atomic weight of the target material. Both the scattering and the slowing down of electrons increase with increasing target atom mass. Moreover high-energy electrons in the vicinity of heavy metal nuclei emits bremsstrahlung. In the present work, the energy loss of electrons when it traverses the layered metallic targets, has been calculated as the total energy loss which is the sum of the energy loss by ionisation and that due to bremsstrahlung emission. The effect of electron energy loss is observed in the modification in track properties of polyallyldiglycol carbonate (PADC). The etching behaviour of PADC was improved which might be due to the effect of bremsstrahlung emission. A comparative study has been carried out to study the effect of metallic targets of different atomic numbers on the energy loss phenomena. [Copyright &y& Elsevier]

Ba(Zr x Ti 1− x )O 3 (BZT) thin films were deposited on (100)MgO substrates by RF-magnetron reactive sputtering using metal targets. Coplanar capacitor test structure with Pt/Au electrode based on BZT/MgO layer was fabricated by sputtering, photolithography, and etching processes. 500-nm-thick BZT thin films for high frequency performance showed a single perovskite phase and a high crystallinity on the MgO substrate with only a (001)/(100) orientation at an optimum deposition conditions. The BZT films had a stoichiometric Ba/Ti ratio and epitaxially grew on the MgO substrate. They showed a dense microstructure without cracks or voids. Dielectric properties of BZT thin film ( x =0.26) showed little dispersion at 1–18 GHz. Moreover, low frequency dielectric properties have been characterized using coplanar capacitor structures in a temperature range of −180 to 120 °C. This film showed the high temperature stability of capacitance and loss tangent. These results indicated that we succeeded in depositing high-quality and potentially tunable ferroelectric BZT films for high-frequency applications by RF-magnetron reactive sputtering using metal targets. [ABSTRACT FROM AUTHOR]