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Resistive random-access memories are ideal candidates for next-generation non-volatile memories due to their simple structure, fast response, and low power consumption. One-dimensional nanostructured memories are of particular importance owing to their electron transport confinement in individual components (such as nanorods/nanowires) that can provide extra control to finely tune the electrical performance for stable and reliable memory operations. In this work, vertically oriented one-dimensional TiO 2 nanorods were fabricated via a simple and facile solvothermal technique. Besides, SnO 2 nanoparticles were embedded on TiO 2 nanorods matrix (to form a nanocomposite) and their resistive switching characteristics were evaluated and compared. Although, both devices expressed good resistive switching behavior. However, the nanocomposite device showed superior switching performance than the control (TiO 2 nanorods) one. Moreover, the nanocomposite device demonstrated additional features of multilevel data storage and the prediction of switching probabilities at lower potentials to be applied in neuromorphic computing. The governing resistive switching mechanism was explored, and the role of oxygen vacancies was identified as critical for the switching and charge transport mechanism in the investigated devices. [ABSTRACT FROM AUTHOR]

The aim of this paper is to the synthesis of ZnO– Bi 2 O 3 nanocomposites and characterization their optical, structure, and radiation shielding properties. The microwave –assisted hydrothermal method was adopted for the synthesis of ZnO– Bi 2 O 3 nanocomposites coded as 100Z, 25B075Z, and 50B-50Z. The FTIR and UV spectra of the samples were analysed to obtain their optical and chemical structure features. Also, the gamma-ray photon shielding parameters of the nanocomposites were evaluated using the EPICS2017 data library and by Geant4 Monte Carlo simulations for photon energies 1 keV–10 MeV. The FTIR spectrum analysis confirms the chemical bond structure of the samples. On the other hand, the optical bandgap of the nanocomposites decreased from 3.3 to 2.95 eV as the Bi 2 O 3 nanoparticles increased in the samples. Obtained values of the mass attenuation coefficients of the samples increased in the order of 100Z, 25B075Z, and 50B-50Z. Value of the effective atomic number varies from 13.91 to 29.55, 20.30–55.97, and 26.70–68.97 for 100Z, 25B-75Z, and 50B-50Z correspondingly. The 100Z, 25B075Z, and 50B-50Z nanocomposites were found to have comparable photon shielding ability with respect to high density common commercial glass shields. The present nanomaterials could be adopted as additives to enhance photon shielding competence of existing composite materials. [ABSTRACT FROM AUTHOR]

This research article aims to study the effect of CdO addition on the radiation shielding characteristics of boro-tellurite glasses in the composition of 50B 2 O 3 - (50-x) TeO2- xCdO, where x = 0, 10, 20, 30, 40 and 50 mol%. These glasses were exposed to gamma radiation and the transmitted gamma photons were evaluated for energies varying from 15 keV to 15 MeV using Geant4 simulation toolkit. The number of transmitted photons was then used to characterize the gamma shielding for the studied glasses in terms of linear/mass attenuation coefficients, MFP, Z eff , and HVL. The simulation outcomes were theoretically confirmed by using Phy-X software. The beta (electron) shielding characterization of the involved glasses was also investigated by determining the projectile range and stopping power using ESTAR software. Additionally, the fast neutron shielding characterization of the glasses was achieved by evaluating removal cross-section (Σ R). The results reveal that the CdO has a small influence on the shielding performance of the boro-tellurite glasses against gamma, beta, and neutron radiations. The shielding performance of the boro-tellurite glasses was compared with that of common shielding materials in terms of MFP. It can be concluded that the boro-tellurite glasses regardless of the concentration of CdO content have promising shielding performance to be used for radiation applications. [ABSTRACT FROM AUTHOR]

The gamma-ray and fast/thermal neutron shielding properties of bismo-borate glasses modified with Nd 2 O 3 in the form B 2 O 3 –Bi 2 O 3 –SrO-Nd 2 O 3 (BBSN0.0-BBSN5.7) were investigated. The newly developed Phy-X/PSD software and Geant4 simulation code were performed to achieve this goal by evaluating several parameters such as MAC, gamma photons dose rate, FNRCS, and scattering/absorption lengths and cross sections for thermal neutrons. At low photon energy; 0.015 MeV, MAC values varied from 76.72, 76.57, 76.43, 76.29, 76.10, and 75.93 cm2 g−1 for BBSN0.0, BBSN1.0, BBSN2.0, BBSN3.0, BBSN4.3, and BBSN5.7, respectively. The HVL followed reversible trend as follows; BBSN0.0 > BBSN1.0 > BBSN2.0 > BBSN3.0 > BBSN4.3 > BBSN5.7. The highest values for Z eff were found at low energy photon range (0.015 MeV) with the values of 76.71, 76.35, 76.00, 75.65, 75.21, and 74.75, while the lowest values were found at 1.5 MeV; 21.32, 21.42, 21.52, 21.61, 21.73, and 21.87 for BBSN0.0 – BBSN5.7, respectively. The gamma dose rate has a dramatic decrease with increasing the glass thickness from 1 mm to 5 mm. Furthermore, glasses with the highest concentration of Nd 2 O 3 show the best thermal/fast neutron shielding capability among the investigated glasses. One can conclude that BBSN5.7 glass owns the best shielding capacity among all BBSN glasses due to the highest LAC values comparing to other selected ones. [ABSTRACT FROM AUTHOR]

In this paper, the hydrogen storage properties of the MmNi 4.6 Al 0.4 and MmNi 4.6 Fe 0.4 compounds are compared experimentally and theoretically. The experimental curves of the activation process, experimental isotherms of absorption and the Van't Hoff's plot were first investigated. Following that, a theoretical model is contrasted with the experimental data. The mathematical equations of this model contain parameters, such as the number of hydrogen atoms per site (n 1 , n 2), the densities of the receiving sites (N 1m , N 2m), and the energy parameters (P 1 , P 2). All these parameters are obtained by numerically adjusting the experimental data. Depending on the applied temperature, the relevant parameters of the suggested model were identified and described. Entropy, internal energy, and other thermodynamic variables that govern the absorption reaction were all calculated and displayed as a function of pressure and temperature. • Measurement of hydrogen absorption isotherms by MmNi 4.5 Al 0.4 and MmNi 4.6 Fe 0.4 compounds. • Validation of experimental data by a mathematical model using statistical physics. • Determination of the steric parameters governing the absorption reaction. • Calculation of the thermodynamic functions of the absorption reaction. [ABSTRACT FROM AUTHOR]

• A hybrid power, heating, cooling and fresh water generation system is designed. • SOFC-GT, ORC, HDH desalination are integrated with utilization of LNG cold energy. • The system has net energy efficiency of 85.65% and exergy efficiency of 63.29%. • Sensitivity analysis and detailed exergy destruction investigation is reported. • The parallel system configuration provides flexibility and variable output range. A multigeneration system is proposed to address the high temperature exhaust emissions of solid oxide fuel cells and the increasing demand for power, fresh water, cooling, and heating utilities. Thermodynamic assessment of the hybrid solid oxide fuel cell system integrating gas turbine, organic Rankine cycle (ORC) and humidification dehumidification (HDH) desalination system with liquified natural gas cold energy utilization is conducted. SOFC being the primary mover, the influence of key parameters such as cell operating temperature and pressure on overall system output performance is studied. In addition to the conventional cascade heat recovery mode, a parallel configuration of the system is also designed and analyzed for varying load demand. This design provides flexibility in operation. Under design conditions the net power generated, heating load, cooling load and fresh water produced by the system are 2390 kW, 584 kW, 58 kW and 209 kg/hr, respectively. The results show that the system net energy, exergy and electrical efficiencies are 85.65%, 63.29% and 64.51%. The major exergy destruction sources are the air preheater, afterburner and water preheater contributing to 28.3%, 16.5% and 15.8% of the total destruction. The exergy destruction of the SOFC subsystem is highest in both series and parallel designs amounting to about 888 kW. In parallel mode, the exergy destruction rate of ORC decreases from 15% to 10% while that of heating and desalination subsystem increase by 2% each. The parallel configuration is flexible in terms of output power, heating load and produced fresh water that have a range of 2303–2470 kW, 258–784 kW and 189–2493 kg/hr, respectively. [ABSTRACT FROM AUTHOR]