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High grain-Cd-accumulating rice variety Yongyou 9 was planted in Cd-contaminated farmland in Taizhou City, Zhejiang Province, China to study the effects of 5-aminolevulinic acid (ALA) and 24-epibrassinolide (EBR) on Cd accumulation in brown rice. Results showed that the exogenous ALA and EBR had no significant effects on agronomic traits, soil pH and total Cd content in soil, but had some effects on the available Cd content in soil, and significantly influenced the Cd accumulation in the different parts of rice. Results also showed that 100 mg/L exogenous ALA significantly reduced the Cd accumulation in brown rice to blow the food safety standard (0.2 mg/kg), and also significantly reduced the Cd contents in the roots and culm of rice. However, 200 mg/L exogenous ALA treatment increased the Cd content in brown rice remarkably. In addition, 0.15 mg/L EBR treatment increased Cd accumulation in roots, culm, leaves and brown rice notably, whereas 0.30 mg/L exogenous EBR treatment reduced the Cd accumulation in brown rice properly, but it was not significant. Therefore, proper concentration of ALA can effectively reduce the Cd accumulation in brown rice, which can be used as an effective technical method for the safe production of rice in Cd polluted farmland. Keywords: rice, Cd-contaminated soil, 5-aminolevulinic acid, 24-epibrassinolide, Cd accumulation

In this work, bottom-Schottky-structure InGaZnOx (IGZO) Schottky barrier diodes (SBDs) with sputtered PtOx anodes were fabricated and annealed in oxygen at different temperatures. Critical parameters and negative bias stress (NBS) stability of SBDs with different annealing temperatures are investigated. With the annealing temperature increases, the barrier height and rectification ratio of the SBDs exhibited a rising-then-declining trend, while the ideality factor slightly increased until 200 °C. The SBDs show up overall reliability except for a leakage current rising trend under light, which can be attributed to free electron generation from the ionized oxygen vacancy. Among all the SBDs, the 175 °C annealed ones exhibited the best overall performance, including a high barrier height of 0.89 eV, an ideality factor of 1.14, and a large rectification ratio of over 108. Compared to the initial SBDs, the annealed ones showed up great improvement in NBS stability except for the 200 °C annealed ones, which was permanently degraded and not able to recover to original states. According to experimental result analysis and IGZO material characteristics, a stability model based on the subgap trap transition from V O 2 + to VO and new V O 2 + creation was proposed, which applies to both the short-term and long-term NBS tests. The results above demonstrate that oxygen annealing at appropriate temperature is an effective method to improve both device performance and NBS stability for PtOx–IGZO SBDs. [ABSTRACT FROM AUTHOR]

Beta-phase gallium oxide (β-Ga2O3) has attracted increasing attention in the field of power electronic devices due to its ultra-wide bandgap and high Baliga figure-of-merit. However, the premature breakdown deteriorated with the increase in device area, hindering the scale-up of the current rating. In this work, we unveil the formation and characteristics of killer defects responsible for the premature breakdown in an Si-doped (001) β-Ga2O3 epitaxial layer grown by halide vapor phase epitaxy. The killer defects feature a line-shaped morphology along the [010] orientation. Specifically, the high-resolution transmission electron microscopy characterization links the line-shaped defects to underlying voids. These voids are surrounded by amorphous phase regions, and the transition from amorphous phase to crystalline phase results in twins extending along the [010] orientation, which eventually become line-shaped defects on the wafer. Additionally, the defect area exhibits smaller capacitance and lower surface potential compared to the defect-free region. This is attributed to the absence of local ionized donors in the defect area, leading to electric field concentration in this region. This study systematically investigates a killer defect in β-Ga2O3, which contributes to the scale-up process of β-Ga2O3 power devices and advances their application. [ABSTRACT FROM AUTHOR]

Ga2O3 has been considered as one of the most suitable materials for x-ray detection, but its x-ray detection performance is still at a low level due to the limitation of its quality and absorbance, especially for hard x-ray. In this work, the effects of growth temperature and miscut angle of the sapphire substrate on the crystal quality of Ga2O3 thin films were investigated based on the MOCVD technique. It was found that the crystal growth mode was transformed from island growth to step-flow growth using miscut sapphire substrates and increasing growth temperature, which was accompanied by the improvement of the crystal quality and the reduction of the density of trapped states. Ga2O3 films with optimal crystal quality were finally prepared on a 4° miscut substrate at 900 °C. The x-ray detector based on this film shows good hard x-ray response with a sensitivity of 3.72 × 105μC·Gyair−1·cm−2. Furthermore, the impacts of Ga2O3 film crystal quality and trap density on the x-ray detector were investigated in depth, and the mechanism of the photoconductive gain of the Ga2O3 thin-film x-ray detector was analyzed. [ABSTRACT FROM AUTHOR]

Sensitive high‐energy photon detection from UV to X‐ray and high‐resolution array imaging are critical for medical diagnosis, space exploration, and scientific research. The key challenges for high‐performance photodetector and imaging arrays are the effective material and device design strategies for the miniaturization and integration of the device. Here, photon‐controlled diodes (i.e., the detector has rectifying characteristics only under light irradiation) are proposed for high‐resolution and anti‐crosstalk array imaging applications without integrating the switching element. Based on ultra‐wide bandgap semiconductor Ga2O3, the sensitive DUV/X‐ray photon‐controlled diodes are realized by the design of high‐resistance Ga2O3 film and high‐barrier contact. The device exhibits remarkable detection performance, including high photo‐responsivity (168 A W−1) and specific detectivity (1.45 × 1015 Jones) under DUV illumination, as well as a high sensitivity (1.23 × 105 µC Gyair−1 cm−2) under X‐ray light. Moreover, the low dark current and excellent rectification characteristics are obtained. Furthermore, its potential for high‐density and anti‐crosstalk array imaging applications is verified. These results not only bring forth new insights in the implementation of high‐performance DUV/X‐ray photodetector, but also pave a feasible way to realize high pixel density detector array through the simplified fabrication process for high‐resolution imaging applications. [ABSTRACT FROM AUTHOR]

This work investigated the single-event effects (SEE) of NiO/β-Ga2O3 heterojunction diodes (HJDs) irradiated by 1.86 GeV tantalum ions with linear energy transfer over 80 MeV cm2/mg. The HJDs exhibited radiation responses with the early single-event leakage current (SELC) degradation until the fatal single-event burnout (SEB) failure, which was far below their breakdown voltages. Meanwhile, the surface morphology revealed the SELC damage expressed as burnout of topside NiO and metal stacks, while the SEB damage was observed as a burned hole in the β-Ga2O3 epitaxial layer. According to technology computer aided design simulations, the thicker p-type region in HJDs could further alleviate the electric field crowding effect exacerbated by the heavy-ion strike because of the extension of charge distribution in the p-type region. The SEB threshold was raised to 250 V by thickening the NiO layer to 300 nm. As for the SELC degradation process along with the burnout of topside stacks in HJDs, we supposed the probable reason was the intolerance of NiO to the high electric field under the SEE. This paper analyzed the SEE mechanism in β-Ga2O3 diodes and paved the way for heavy-ion irradiation hardening. [ABSTRACT FROM AUTHOR]

Thyroid cancer is the most common type of endocrine cancer, and most patients have a good prognosis. However, the thyroid cancer differentiation status strongly affects patient response to conventional treatment and prognosis. Therefore, exploring the molecular mechanisms that influence the differentiation of thyroid cancer is very important for understanding the progression of this disease and improving therapeutic options. In this study, SETMAR as a key gene that affects thyroid cancer differentiation is identified. SETMAR significantly regulates the proliferation, epithelial‐mesenchymal transformation (EMT), thyroid differentiation‐related gene expression, radioactive iodine uptake, and sensitivity to MAPK inhibitor‐based redifferentiation therapies of thyroid cancer cells. Mechanistically, SETMAR methylates dimethylated H3K36 in the SMARCA2 promoter region to promote SMARCA2 transcription. SMARCA2 can bind to enhancers of the thyroid differentiation transcription factors (TTFs) PAX8, and FOXE1 to promote their expression by enhancing chromatin accessibility. Moreover, METTL3‐mediated m6A methylation of SETAMR mRNA is observed and showed that this medication can affect SETMAR expression in an IGF2BP3‐dependent manner. Finally, the METTL3‐14‐WTAP activator effectively facilitates the redifferentiation of thyroid cancer cells via the SETMAR‐SMARCA2‐TTF axis utilized. The research provides novel insights into the molecular mechanisms underlying thyroid cancer dedifferentiation and provides a new approach for therapeutically promoting redifferentiation. [ABSTRACT FROM AUTHOR]

Gallium oxide (Ga2O3), with an ultrawide bandgap corresponding to the deep ultraviolet (DUV) range, has attracted significant attention in optical filter‐free photodetectors. In practical terms, DUV photodetectors employed in extreme conditions, for example, flame detection and space exploration, face the challenges of performance degradation caused by high/low‐temperature transformation. Here, DUV photodetectors are tailored with high durability and stability by one‐step‐grown β‐Ga2O3 films via pulsed laser deposition. A high‐oxygen‐pressure scheme effectively addresses the issue of film‐free deposition at specifically high temperatures, facilitating the formation of polycrystalline high‐resistivity β‐Ga2O3 films. As a result, the devices exhibit outstanding performance, including a low dark current (4.4 pA @30 V), high photoresponsivity (147.36 A W−1), and fast response time (3.1/22.6 ms). Additionally, the photoresponse performance shows minimal degradation at high temperatures up to 300 °C and even improves at low temperatures down to −100 °C, ranking it among the most robust DUV photodetectors. The mechanism of photoresponse, involving the exciton formation, bandgap evolution, carrier‐phonon scatter, etc., is also elucidated in a wide temperature range. This work provides an efficient solution for developing robust Ga2O3 DUV photodetectors with excellent performance for extreme‐condition applications. [ABSTRACT FROM AUTHOR]

Ga2O3 photodetectors with demonstrated high sensitivity provide a potential subversive scheme for solar‐blind photodetection. However, the planar structure and the relatively slow response speed of the device have restricted the integration and application of Ga2O3 photodetectors. Herein, a narrow SiO2 barrier layer is introduced on the commercial SiC substrate, and a vertical photodetector is realized based on β‐Ga2O3/SiO2/SiC heterostructure with controllable tunneling effect by tailoring the band structure at the interface. The developed device exhibits unconventional rectification characteristics and photoresponse performance in different biasing modes owing to the controllable tunneling effect at the interface. In particular, the photodetector achieves a high responsivity (186.8 A W−1) under solar‐blind illumination at reverse bias, while exhibiting obvious advantages in dark current (3 pA), photo‐to‐dark current ratio (8.8 × 106), linear dynamic range (138.8 dB), and specific detectivity (1.4 × 1015 Jones) at forward bias. The photodetector also demonstrates excellent photoresponse stability after 6 months in air without encapsulation. In addition, an alternating biasing strategy, inspired by its bidirectional operability, is proposed to suppress the persistent photoconductivity effect and increase the decay speed by 1.23 × 105 times. This work provides a referable strategy for the further development of high‐performance Ga2O3‐based photoelectronics. [ABSTRACT FROM AUTHOR]

High-performance radiation detectors are essential in many sectors spanning medical diagnostics, nuclear control, and particle physics. Ultrawide bandgap semiconductor materials have become one of the most promising candidates due to their excellent performance. Here, based on β-Ga2O3, a Schottky diode-type alpha particle detector was demonstrated. In order to reduce the reverse leakage current of the large-area device, the metal-oxide electrode PtOx was introduced to form high-barrier contacts (1.83 eV) with Ga2O3. The device exhibits a low leakage current density of 63 pA/cm2 at −100 V and apparent energy spectra of 241Am generated alpha particles with an energy of 5.486 MeV at various reverse voltages from −40 to −120 V. The charge collection efficiency (CCE) and energy resolution of the device (at −120 V) are 31.7% and 15.3%, respectively. Meanwhile, the mechanism of interaction between alpha particles and β-Ga2O3 was analyzed, and a 45° oblique incidence was adopted to increase the deposited energy of alpha particles in the depletion region. Furthermore, the differences between actual CCE and theoretical CCE are investigated as guidance for further improving detector performance. This work reveals the great potential and good prospects of Ga2O3 as an economical, efficient, and radiation-resistant ionizing radiation detector. [ABSTRACT FROM AUTHOR]

Poor sealing of gas extraction boreholes is one key to restrict gas extraction efficiency. In this paper, a novel borehole sealed quality detection device for the gas extraction of a coal mine is developed based on the theory of air leakage. By comparing the amount of gas extracted at different test points, it is possible to determine whether there is air leakage around the borehole, and the specific leakage position and leakage amount. Moreover, this device has the advantages of simple operation and a short test period. Based on the above analysis, a corresponding air leakage disposal method was proposed to handle the leaky boreholes. Field tests showed that the air–gas mixture flow in the test borehole was reduced by a factor of approximately 1.55 and the concentration of pure seam gas was increased approximately six times after the disposal of the air leaks. The combination of the leakage disposal method and the leakage detection device can accurately seal the borehole at the position of the leak, thus effectively ensuring the effectiveness of gas extraction from the borehole. The findings have important implications for improving the efficiency of gas extraction in coal mining operations. [ABSTRACT FROM AUTHOR]

β-Ga2O3 power diodes were expected to possess low turn-on voltage (V on), low reverse leakage (J R), and high blocking capability for low power losses. In this work, a low V on (0.48 V) β-Ga2O3 heterojunction barrier Schottky diode (HJBS) with tungsten Schottky contact was achieved. Benefitting from the lateral depletion of p+-NiO to suppress J R originating from the low Schottky barrier, the blocking capability of β-Ga2O3 HJBS was enhanced. The spacing width of p+-NiO was systematically studied to reveal its modulation effect on forward and reverse characteristics. This work provides a promising strategy for improving rectifier efficiency of β-Ga2O3 diodes. [ABSTRACT FROM AUTHOR]

To address the critical issue of polarization during lithium-ion battery charging and its adverse impact on battery capacity and lifespan, this research employs a comprehensive strategy that considers the charging duration, efficiency, and temperature increase. Central to this approach is the proposal of a novel negative pulsed charging technique optimized using the Non-Dominated Sorting Genetic Algorithm II (NSGA-II). This study initiates the creation of an intricate electrothermal coupling model, which simulates variations in internal battery parameters throughout the charging cycle. Subsequently, NSGA-II is implemented in MATLAB to fine-tune pulsed charging and discharging profiles, generating a Pareto front showcasing an array of optimal solutions tailored to a spectrum of goals. Leveraging the capabilities of the COMSOL Multiphysics software 6.2 platform, a high-fidelity simulation environment for lithium-ion battery charging is established that incorporates three charging strategies: constant-current (CC) charging, a multi-stage constant-current (MS-CC) charging protocol, and a pulsed-current (PC) charging strategy. This setup works as a powerful instrument for assessing the individual effects of these strategies on battery characteristics. The simulation results strongly support the superiority of the proposed pulsed-current charging strategy, which excels in increasing the battery temperature and amplifying battery charge capacity. This dual achievement not only bolsters charging efficiency significantly but also underscores the strategy's potential to augment both the practical utility and long-term viability of lithium-ion batteries, thereby contributing to the advancement of sustainable energy storage solutions. [ABSTRACT FROM AUTHOR]