Irradiation Temperature Research Articles

Investigation of the damage behavior in SiC without any additives irradiated with Si ions by GIXRD, Raman and TEM

The SPS-prepared SiC without any additives was irradiated with 15.9 MeV Si ions at room temperature and 500 °C. The damage behavior was investigated by grazing incident X-ray diffraction (GIXRD) spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM). GIXRD and Raman spectra show that the disorder of SiC increases and the lattice swelling occurs with the increase of irradiation at room temperature. High temperature irradiation was associated with the reduction of swelling and the recovery of disorder. TEM results indicate that at room temperature, with increasing dose, the material transitions from slight amorphization to complete amorphization. The amorphization dose is estimated to be around 1.2 dpa. The combined effects of stacking faults, high-energy ions accompanied by higher electronic energy loss inducing displacement cascades, and cascade-induced annealing delay damage accumulation, leading to an increased critical dose for amorphization. Moreover, the transient thermal spikes due to higher electronic energy loss, leading to defect annealing and the formation of Frank loops at lower irradiation temperatures.

Improving the efficiency of solar photovoltaics by means of geothermal cooling: A year-long test campaign

Heating up of photovoltaic modules during operation results in a significant power output reduction. This effect is especially relevant in regions with the highest photovoltaic potential, where irradiance and ambient temperature are particularly high. In this paper, a novel low enthalpy geothermal cooling system that improves the efficiency of a commercial solar module is described and experimentally validated. Two heat exchangers, one attached to the backside of the module, and another introduced inside a 15 m deep borehole, are connected in a closed circuit. A water-based coolant is pumped through the system, evacuating the excess heat from the module, and dissipating it underground in a clean and efficient manner, without additional water consumption after filling the system.The performance of the cooling system was experimentally tested by implementing it, for the first time, in a single-axis solar tracking isolated photovoltaic facility. Extensive tests were carried out in Spain, between September 2021 and August 2022 under a wide variety of environmental conditions. The efficiency improvement system has demonstrated its technical feasibility over a one-year period, showing a peak net efficiency improvement up to 13.4 %. Moreover, a positive net efficiency improvement has been demonstrated all year long, even during the winter months.

Microstructural evolution of ion-irradiated commercially pure titanium

Radiation-induced dislocation loop evolution in ion-irradiated commercially pure (CP) Ti was investigated through both ex situ 4 MeV Ar beams and by in situ TEM irradiation with 1 MeV Kr ion beams at different temperatures. The dominant mechanism for dislocation loop growth was loop coalescence. Both <a>- and c-component loops exhibited an increase in size and density with increased irradiation dose and temperature. C-component loops were observed only after reaching a threshold incubation dose (TID). In CP Ti, these loops initiated at lower doses compared to previous observations in Zr, and the TID decreased with increasing temperature.

Optimal Allocation of Fast Charging Stations on Real Power Transmission Network with Penetration of Renewable Energy Plant

Because of their stochastic nature, the high penetration of electric vehicles (EVs) places demands on the power system that may strain network reliability. Along with increasing network voltage deviations, this can also lower the quality of the power provided. By placing EV fast charging stations (FCSs) in strategic grid locations, this issue can be resolved. Thus, this work suggests a new methodology incorporating an effective and straightforward Red-Tailed Hawk Algorithm (RTH) to identify the optimal locations and capacities for FCSs in a real Aljouf Transmission Network located in northern Saudi Arabia. Using a fitness function, this work’s objective is to minimize voltage violations over a 24 h period. The merits of the suggested RTH are its high convergence rate and ability to eschew local solutions. The results obtained via the suggested RTH are contrasted with those of other approaches such as the use of a Kepler optimization algorithm (KOA), gold rush optimizer (GRO), grey wolf optimizer (GWO), and spider wasp optimizer (SWO). Annual substation demand, solar irradiance, and photovoltaic (PV) temperature datasets are utilized in this study to describe the demand as well as the generation profiles in the proposed real network. A principal component analysis (PCA) is employed to reduce the complexity of each dataset and to prepare them for the k-means algorithm. Then, k-means clustering is used to partition each dataset into k distinct clusters evaluated using internal and external validity indices. The values of these indices are weighted to select the best number of clusters. Moreover, a Monte Carlo simulation (MCS) is applied to probabilistically determine the daily profile of each data set. According to the obtained results, the proposed RTH outperformed the others, achieving the lowest fitness value of 0.134346 pu, while the GRO came in second place with a voltage deviation of 0.135646 pu. Conversely, the KOA was the worst method, achieving a fitness value of 0.148358 pu. The outcomes attained validate the suggested approach’s competency in integrating FCSs into a real transmission grid by selecting their best locations and sizes.

Optimizing solar panel maximum power point tracking and parasitic parameter extraction in partial shading with Enhanced Slime Mold optimization

Solar energy offers several environmental, economic, and energy security advantages. Parasitic parameters and shading on solar panels can reduce efficiency. This paper presents a bio-inspired Enhanced Slime Mold (ESM) algorithm search strategy to find near-optimal power points by simulating the behaviour of slime molds in a virtual environment. In a solar panel, proposed ESM provides not only for parameter extraction but also serves as Maximum Power Point Tracking (MPPT) during Partial Shading Conditions (PSC). The proposed ESM dynamic behaviour is examined under solar irradiation and various temperature conditions. The effectiveness of proposed technique has been validated by extracting parameters from conventional polycrystalline and monocrystalline modules in the form of a 5 S–5P arrangement. In the instance of MPPT operation, the proposed ESM algorithm is compared with Ant Bee Colony and Perturb& Observe (ABC-PO) to determine its efficacy. Moreover, during extraction of unknown parameters of solar cell ESM is compared with existing optimization algorithms such as Artificial Bee Swarm Optimization (ABSO), Genetic Algorithm (GA), Covariant Matrix (CM), Ant Bee Colony (ABC), and Advanced Particle Swarm Optimization (APSO). In this connection, proposed ESM algorithm is superior to the above-mentioned algorithms due to high accuracy, a smaller number of computations, and minimum computational time.

Chance-Constrained Optimal Design of PV-Based Microgrids under Grid Blackout Uncertainties

A grid blackout is an intractable problem with serious economic consequences in many developing countries. Although it has been proven that microgrids (MGs) are capable of solving this problem, the uncertainties regarding when and for how long blackouts occur lead to extreme difficulties in the design and operation of the related MGs. This paper addresses the optimal design problem of the MGs considering the uncertainties of the blackout starting time and duration utilizing the kernel density estimator method. Additionally, uncertainties in solar irradiance and ambient temperature are also considered. For that, chance-constrained optimization is employed to design residential and industrial PV-based MGs. The proposed approach aims to minimize the expected value of the levelized cost of energy (LCOE), where the restriction of the annual total loss of power supply (TLPS) is addressed as a chance constraint. The results show that blackout uncertainties have a considerable effect on calculating the size of the MG’s components, especially the battery bank size. Additionally, it is proven that considering the uncertainties of the input parameters leads to an accurate estimation for the LCOE and increases the MG reliability level.

A Concept of Online Refueling TRISO-Fueled and Salt-Cooled Reactor

This paper introduces a novel concept of a TRISO-fueled salt-cooled reactor (TFSCR). The core contains circulating pipes filled with molten salt carrying TRISO particles. The reactor achieves online refueling by slowly circulating the molten salt through the pipeline. The reactor utilizes the same molten salt as the coolant and graphite as the moderator. The reactor design has the characteristics of safety, economy, and nonproliferation. TRISO particles exhibit greater resistance to neutron irradiation, corrosion, oxidation, and high temperatures compared to conventional fuels. A molten salt-cooled reactor can also operate at higher temperatures, consequently enhancing power generation efficiency. Furthermore, lower operating pressures can mitigate the risk of significant damages and loss of coolant caused by accidents, thereby enhancing reactor safety. This paper presents the basic nuclear design of TFSCR under the assumptions concerning the average fuel power density, the volumetric core power density, and the core temperature. At the same time, the feasibility of online refueling and long-life operation was evaluated by fuel burnup calculation.

Qualitative Model of Electrical Conductivity of Irradiated Semiconductor

There is constructed a qualitative model of the electrical conductivity of semiconductors irradiated with sufficiently high-energy particles. At certain conditions (irradiation temperature and dose, and subsequent thermal treatment), high-energy particles fluence, in addition to primary and secondary point radiation defects, forms a number of nano-sized disordered regions, highly conductive (“metallic”) compared to the semiconductor matrix. Their high total volume fraction can lead to the charge major carriers’ effective Hall mobility significantly exceeding that of the matrix. Due to elastic stresses created by these disordered inclusions, a high concentration of point radiation defects tends to form defective shells. In certain temperature ranges, such nanosized core-shell structures act as capacitors storing the electric charge sufficient for the Coulomb blockade of the major current carriers. Transformation of high-conductive inclusions into low-conductive (“dielectric”) ones manifests in a noticeable decrease in effective Hall mobility. The proposed model qualitatively explains all the experimental data available on single-crystalline n- and p-type silicon irradiated with high-energy electrons and protons and isochronously annealed.

The Impact of Rainfall on Oil Palm Production: A Case Study in Berau Regency, East Borneo, Indonesia

This study examines the impact of rainfall on oil palm growth and productivity in the Berau region of East Borneo, Indonesia. The research utilized qualitative and quantitative field studies, employing correlation and regression analysis. The study focused on the oil palm plantation area as its subject. Data was collected from a plantation in the Berau region of East Borneo. The plantation has homogeneous plant age (same planting year, 2009) and homogeneous progeny (Scofindo variety) and is included in the company's core plantation. The observation parameters included rainfall, rainy days, fresh fruit bunches, and plant productivity. It was found that rainfall and rainy days have an impact on oil palm productivity. The regression results indicate a positive correlation between rainfall and oil palm productivity, with a correlation coefficient of 0.025109171. However, rainy days have a negative effect on oil palm productivity, with a correlation coefficient of -0.036778304, despite being positively correlated with rainfall. The correlation coefficient of 0.768386269 indicates a direct impact on reducing oil palm productivity. Rainfall indirectly affects oil palm productivity by influencing temperature, humidity, intensity, and length of daily irradiation. These factors directly affect the productivity of oil palm plants.

Preparation of Durable Superhydrophobic Coatings Based on Discrete Adhesives

Due to the low adhesion observed at the interface between solid and liquid, superhydrophobic coatings hold significant promise for various applications, such as self-cleaning, anti-corrosion, anti-icing, and drag reduction. However, a notable challenge hindering their widespread adoption in these domains lies in their delicate durability. In this study, we propose a straightforward method for preparation. The fluorosilicone resin is initially discretized through a gradual introduction of nonsolvent into its solution, followed by thorough mixing and stirring with silica nanoparticles. The resulting mixture is then sprayed onto the substrate surface after drying, forming a self-similar, porous, and rough structure extending from top to bottom. This process yields a coating exhibiting excellent chemical and mechanical durability simultaneously. Using this approach, we achieved a superhydrophobic coating with a contact angle of 156° and a roll angle of 2.2°, with water droplet adhesion of only 10.8 ± 0.4 µN. Remarkably, the coating maintained excellent superhydrophobicity even after undergoing sandpaper abrasion (10 m), tape peeling (30 times), and prolonged water impact (60 min), showing its robust mechanical stability. Furthermore, following exposure to acid, alkali, and aqueous solutions (7 days), UV irradiation (10 days), and extreme temperature variations (–20 °C to 80 °C), the coatings retained their superhydrophobic properties and exhibited good chemical durability. This method offers a novel approach to enhance the durability and practicality of superhydrophobic coatings.

Prediction of photovoltaic power using the Johansen VECM cointegration method in the Reduit region, Mauritius

ABSTRACT Accurate forecasting of the photovoltaic (PV) power output is crucial for the stability of power systems. In this paper, the Johansen vector error correction model (VECM) cointegration approach is used to predict the PV power output of a PV system in the tropical island of Mauritius. The predicted PV power output is compared to measured PV power output under real conditions. Only solar irradiation and PV cell temperature are considered as predictors and data is recorded from a 20 kW PV system installed in the Phoenix region in Mauritius. The performance of Johansen model is then compared to a conventional ANN forecasting model. Results showed that the Johansen VECM cointegration approach outperformed the Artificial Neural Network (ANN) model with RMSE and MAE values of 298.9W and 221.6W, respectively. The Johansen model proved to be a powerful tool, showing good potential for PV power forecasting.

Characterization of an enhanced formulation N-(3-methoxypropyl) acrylamide polymer gel dosimeter by the addition of an organic sensitizer for clinical practice

Polymer gel dosimeters are being developed and improved to perform measurements of radiation dose distributions in 3-dimensions (3-D) for the purpose of patient specific quality assurance for cancer patients and the configuration of treatment planning systems. The effect of organic glucose sensitizer (GL) material on N-(3-methoxypropyl) acrylamide polymer gel dosimeter (NMPAGAT) was presented in this study and evaluated after irradiation using nuclear magnetic resonance (NMR) read-out technique in terms of spin–spin relaxation rate (R2) of hydrogen protons within the water molecule. The improved tissue equivalent polymers of GL-NMPAGAT were irradiated using a medical linear accelerator with photon beams with doses up to 20 Gy, energies range 6–15 MV, dose rates range 50–500 cGy/min, and irradiation temperatures range 15–25 °C. The R2 dose sensitivity of GL-NMPAGT polymer with a concentration of 25 % wt GL was improved significantly and found to be two times higher than the same gel without GL in the linear dose response of 0.07–8 Gy. The 0.07 Gy represents the minimum detectable dose in the improved dosimeters. The dosimeter was found stable within a period of up to two weeks after irradiation, which is significant. No significant dose rate, energy dependence, and irradiation temperature for the dosimeter was observed over the range studied. There is decrease in R2 values with increasing scanning temperature. The gel is water equivalent and has theoretical energy-independent response from 0.1 to 20 MeV with density of 1.023 ± 0.003 g/cm3 and Zeff of 7.53. The results of the improved dosimeter in this study (i.e., 100 %, 0.32 s−1 Gy−1, and 8 Gy linearity) are toward the upper limit compared to other polymer gel dosimeters even with sensitizer additives.

Reaction kinetics of Li4SiO4 and Li4Ti5O12 in biphasic breeder ceramics after lithium burn-up

Advanced ceramic breeder (ACB) pebbles consisting of the two phases Li4SiO4 and Li2TiO3 serve as the EU reference tritium breeding material. In the present study, the phase stability with regard to a lithium-burn-up is investigated. The loss of lithium due to its transmutation will lead to a compositional change of the breeder material. Li4SiO4 and Li2TiO3 will partly be transformed to the lithium-poorer phases Li2SiO3 and Li4Ti5O12, respectively. However, from the phase diagram it is anticipated that only Li2SiO3 will occur as a third phase after a lithium burn-up as the generated Li4Ti5O12 is expected to further react with Li4SiO4 to form again Li2TiO3 and more Li2SiO3. Therefore, the reaction between Li4SiO4 and Li4Ti5O12 and its temperature dependence were investigated in detail and its reaction kinetics were determined. It was found that this diffusion-controlled reaction with an activation energy of 75 kJ/mol (0.78 eV) will slow down at low irradiation temperatures and may not take place at very low temperatures.

Radiation-induced effects in self-passivating W-Cr-Y alloy

Irradiation of the promising self-passivating W-10wt%Cr-0.5wt%Y alloy suggested as the first wall material for demonstration power plant, DEMO, was performed with 5.9 MeV Co2+ ions at 300 °C and 5.6 MeV Fe2+ ions at 500 °C to a dose peak of 12 dpa (displacements per atom). Atom probe tomography and transmission electron microscopy were used to study the chemical compositions of this alloy at the atomic scale before and after irradiation. Before irradiation, the microstructure consists of a supersaturated bcc solid solution (αW,Cr) phase with an average grain size of about 1 µm. Cr-enriched nanoscale clusters with an average size of (2.0 ± 0.4) with a density of (6.3 ± 0.5) ×1024 m−3 and (1.8 ± 0.4) nm with a density of (5.6 ± 0.5) ×1024 m−3 were found in the damage range after irradiation at 300 and 500 °C, respectively. The Cr concentration in the Cr-enriched clusters increased from 48 at.% to 78 at.% with increasing the irradiation temperature from 300 to 500 °C, but the average size slightly decreased. This indicates that Cr clusters are embryos of a Cr-rich (αCr,W) phase. It was found that the Cr-enriched clusters play a dominant role in the radiation-induced hardening of the alloy. Beyond the damage range, no Cr clusters were observed. It was found that the formation of the Cr-enriched clusters in the W-10Cr-0.5Y alloy mitigates the formation of dislocation-type defects.A segregation of yttria particles in the form of platelets was observed at the grain boundaries under irradiation at 500 °C. Although the average yttria particle size remains unchanged after irradiation, the size distribution becomes more uniform and shifts towards smaller sizes. Therefore, the beneficial effect of nanoscale yttria particles on the oxidation resistance and alloy strengthening is expected to remain unchanged after irradiation under current experimental conditions.

Mn3O4 photocatalyzed oxidative amidation of aldehyde and amines for clean synthesis of amides

Amides are widely used in various fields of chemical and pharmaceutical industries. Developing a green and universal amide synthesis method that meets the needs of sustainable chemistry has always been a challenge for amide synthesis. In this paper, a direct and highly selective method for the synthesis of amide was developed under visible light irradiation and room temperature using air as an oxidant. Thanks to the prolongation of the C-H bond (0.1115 nm) and O-H bond (0.1002 nm) during the adsorption of hemiaminal on the Mn3O4 catalyst, and the energy barrier for hemiaminal dehydrogenation (-3.07 eV) is much lower than the energy barrier for dehydration (4.84 eV), thus the formation of imines is suppressed, resulting in highly selective clean production of amides with H2O as byproduct. Therefore, this clean and effective method for obtaining amides is one of the ideal alternative solutions for currently known methods.

Multiscale computational study to predict the irradiation-induced change in engineering properties of fusion reactor materials

In this study, we address the impact of irradiation conditions in a tokamak on the engineering properties of materials, leading to potential degradation of in-vessel components over their lifecycle. Our approach involves a predictive model for irradiation-induced damage, employing a multiscale computational framework. This framework integrates various simulation techniques, including Monte Carlo-based neutronics (OpenMC), dislocation dynamics (DD) using MoDELib, and finite element analysis (FEA) with Code_Aster. This integration offers a versatile solver capable of analysing tokamak components exposed to different irradiation doses and temperature conditions.To showcase the utility of this multiscale computational framework, we present a case study focused on tungsten monoblock designs. We assess the failure probabilities of these designs at different stages of their lifecycle. Neutron heating and damage energy values are obtained from OpenMC neutronics simulations. The neutron heating values serve as volumetric heat sources for the FEA thermal simulation. We calculate the displacement per atom (dpa) across the monoblock at various full power days (day 0, day 100, and day 1000) using the damage energy values. The irradiation-induced defect densities, dependent on temperature and dpa, are inputs to DD microstructural simulations performed on the representative volume element (RVE) using MoDELib. This allows us to obtain the yield stress of the material. Subsequently, the thermal fields from the FEA thermal simulation, along with the dpa and temperature-dependent yield stress from the DD simulation, are implemented for FEA mechanical simulations.To evaluate the failure probability of the monoblock designs at different stages of their lifecycle, we conduct an SDC-IC assessment, incorporating a plastic flow localization rule within the current framework. This comprehensive approach provides insights into the thermo-mechanical behaviour of in-vessel components subjected to neutron irradiation, offering a predictive capability for assessing their performance over time.

Smart monitoring technique for solar cell systems using internet of things based on NodeMCU ESP8266 microcontroller

Rapidly and remotely monitoring and receiving the solar cell systems status parameters, solar irradiance, temperature, and humidity, are critical issues in enhancement their efficiency. Hence, in the present article an improved smart prototype of internet of things (IoT) technique based on embedded system through NodeMCU ESP8266 (ESP-12E) was carried out experimentally. Three different regions at Egypt; Luxor, Cairo, and El-Beheira cities were chosen to study their solar irradiance profile, temperature, and humidity by the proposed IoT system. The monitoring data of solar irradiance, temperature, and humidity were live visualized directly by Ubidots through hypertext transfer protocol (HTTP) protocol. The measured solar power radiation in Luxor, Cairo, and El-Beheira ranged between 216-1000, 245-958, and 187-692 W/m&lt;sup&gt;2&lt;/sup&gt; respectively during the solar day. The accuracy and rapidity of obtaining monitoring results using the proposed IoT system made it a strong candidate for application in monitoring solar cell systems. On the other hand, the obtained solar power radiation results of the three considered regions strongly candidate Luxor and Cairo as suitable places to build up a solar cells system station rather than El-Beheira.

An In Situ transmission electron microscopy study on the synergistic effects of Au-ion irradiation and high temperature on nuclear graphite microstructure

The combined effects of high-temperature and heavy-ion irradiation on Mrozowski cracks (MC) and nuclear graphite crystallographic dimensions have been studied using in situ heating and in situ ion-irradiation in the transmission electron microscope (TEM). Electron transparent lamella of nuclear graphite, IG-110, was irradiated using a 2.8 MeV Au beam at an ion flux of 3.991 ×1010 ion cm−2 s−1 for 70 min at 800 °C. Upon high-temperature irradiation, Mrozowski crack closure was studied quantitatively. The analysis showed linear, positive expansion of nuclear graphite which is significantly different from the dimensional changes previously reported for low-dose neutron irradiation of nuclear graphite in which the material undergoes negative to positive expansion via a turnaround radiation dose. The trend of the thermal expansion coefficient (CTE) of pristine IG-110 in this study is consistent with previous reports in the 100 °C–800 °C temperature region in which the dimensional change ranges from negative to positive values.

Effects of neutron irradiation on failure behavior analysis of high-density bumps under thermo-coupling conditions

As the space environment has conditions such as high vacuum, strong irradiation, and large temperature difference, spacecraft will face a series of challenges such as high-energy particles and extreme temperatures during on-orbit operation, especially neutron irradiation, which has a larger mean free range and a deeper depth of penetration, and which will cause serious damage to the electronic devices. Solder joints, the most failure-prone part of electronic devices, have received extensive attention from related researchers. In this study, the evolution of the microstructure of bumps under neutron irradiation and thermal field coupling conditions is analyzed utilizing scanning electron microscopy (SEM)\\electron backscatter diffraction (EBSD), and the changes in the mechanical properties of the bumps are also analyzed by nanoindentation tests and push-ball experiments. The results show that the incidence of high-energy neutrons generates a large number of atomic vacancies, which exacerbates the Kirkendall effect. The point defects caused by neutrons gather together to form defect clusters. These microscopic defects impede the movement of slip dislocations, leading to the hardening of the material and an increase in elastic modulus. In contrast, the accumulation of a large number of defects leads to the failure of the bump.

Demarcation of suitable site for solar photovoltaic power plant installation in Bangladesh using geospatial techniques

The major goal of this research is to adopt analytical hierarchy process (AHP) based geospatial technique to select suitable zone for the solar photovoltaic (PV) power plants. Nine thematic layers altogether—slope, global horizontal irradiation (GHI), relative humidity, direct normal irradiation (DNI), elevation, distance from major roads, distance from protected areas, rainfall, and land use/land cover (LULC)—are combined through overlay analysis in ArcGIS to create the final map of suitability for the placement of solar photovoltaic (PV) power plants in Bangladesh. This map has been classified into five categories namely, restricted zone, less suitable zone, moderate suitable zone, good suitable zone, and excellent suitable zone. These categories are covered by 7.28%, 16.61%, 28.51%, 27.77%, 21.83% land of total area in Bangladesh respectively. The findings of this research have been presented that ‘the excellent suitable’ and ‘good suitable’ areas for the construction of solar power plants are in the western and northwestern part (Rajshahi, Pabna, Sirajganj, Natore, Naogaon, Chapainawabganj, Bogura, Faridpur, Jessore, Jehenaidha, Magura, Kushtia, Choudanga, Meherpur) of the study area which contain a high value of global horizontal irradiation, direct normal irradiation, elevation and low value of slope, rainfall, temperature, relative humidity. Besides the restricted and less suitable zone for installing solar photovoltaic (PV) power plants indicates a high value of rainfall, slope, temperature, relative humidity and low value of global horizontal irradiation, direct normal irradiation, and elevation. Bangladesh's currently operational solar plants were taken into consideration for this study's validation purposes. The proposed framework may potentially be used in different locales on a national and worldwide scale. This study offers a consistent GIS process for the accurate, inexpensive implementation of a solar energy plan to achieve environmentally friendly goals.