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Molybdenum (Mo) as the refractory metals shows the series of advantageous properties, such as high melting point, excellent high temperature mechanical properties, and good thermal conductivity. In addition, the good antiradiation swelling ability and high compatibility with liquid metals make Mo as the important candidate materials for the advanced nuclear reactors to endure the high temperature, strong corrosion, and high-dose irradiation, such as the fourth generation high-temperature nuclear fission reactor and the fusion reactor. Nevertheless, the application of Mo is limited by the brittle nature at low temperature, the difficult machining, and the poor welding performance. Adding rhenium (Re) into molybdenum to form "rhenium effect" can not only significantly improve the room temperature plasticity and the processability of molybdenum and reduce the plastic brittle transition temperature, but also improve the welding performance and creep resistance. Therefore, it has become a research hotspot of structural materials for the advanced nuclear reactors. The research progress of molybdenum−rhenium alloys (Mo−Re) was summarized in this paper from four aspects as composition design, material preparation, welding performance, and nuclear environmental application assessment, and the problems of Mo−Re alloys used for the advanced reactor engineering were analyzed to provide the reference for the development of high-performance molybdenum−rhenium alloy structural materials.

The deformation and failure characteristics of roadways in stratified rock masses are heavily influenced by the dip angle of the rock layers. Therefore, it is crucial to select an appropriate cross‐sectional shape and support scheme to ensure roadway stability. This study utilizes a discrete element numerical simulation method to systematically investigate the failure modes of roadways in stratified rock masses under varying dip angles. The theory of pressure balance arches is integrated to establish optimal principles for determining the cross‐sectional shape, and corresponding support schemes are proposed for roadways in stratified rock masses. The results indicate that as the dip angle of the rock layers changes, different failure modes occur, ranging from symmetric arch‐shaped collapse to asymmetric wedge‐shaped collapse and overall sliding failure. Based on the self‐stabilizing properties of roadways under pressure balance arches, a straight‐sidewalls and arch‐roof cross‐section is recommended for roadways with arch‐shaped or overall sliding failures in their roofs, and a pentagonal cross‐section is recommended for roadways with wedge‐shaped collapses. The support parameters determined by well‐established empirical criteria are generally applicable to roadways with arch‐shaped or wedge‐shaped roof failures. However, caution should be exercised when applying these parameters to roadways with overall sliding instabilities, as they may result in insufficient design robustness. Finally, a field case study of a copper mine in Zambia is presented to demonstrate the process of recommending appropriate roadway cross‐sectional shape and support scheme. [ABSTRACT FROM AUTHOR]

In this study, we combined the imprinting technique, temperature‐sensitive polymer, and Pickering emulsion polymerization to prepare a temperature‐sensitive porous imprinted polymer. First, the temperature‐sensitive block polymer PDEA‐b‐P (DEA‐co‐AM) was prepared by reversible‐addition fragmentation chain transfer polymerization, and then a temperature‐sensitive porous ReO4− imprinted polymer (ReO4−‐TPIP) was prepared using the Pickering‐like polymerization technique, which was introduced to the preparation of the imprinted polymer. The structure and morphology of the polymer were characterized by FTIR, SEM‐EDS, and BET. The adsorption experiments showed that the maximum adsorption (Q), separation (R), and desorption (D) of ReO4−‐TPIP were 0.1568 mmol/g, 3.41, and 85.22%, respectively, and the adsorption equilibrium could be reached after 120 min, which decreased to 0.1212 mmol/g, 1.23, and 70.01% after repeated use for 11 times. These results indicate that ReO4−‐TPIP has good adsorption and reusability properties. The adsorption studies showed that ReO4−‐TPIP conformed to the zero‐level kinetic model in the pre‐adsorption stage, the quasi‐one‐level kinetic model in the late stage, and the isothermal adsorption process conformed more to the Langmuir model. In addition, in the secondary leach solution of high‐temperature alloys, the purity of rhenium in the solution increased from 35.4119% to 53.4812% after one adsorption/desorption cycle. The prepared ReO4−‐TPIP provides a new material and strategy for the selective separation and purification of rhenium in complex rhenium‐containing solutions for the industry. [ABSTRACT FROM AUTHOR]

In the process of preparation of imprinted polymers, the introduction of external fields, such as magnetic field, microwave field, ultrasonic field, electric field and high‐energy radiation field, to improve the structure and performance of imprinted polymers has become a novel direction of the development of imprinted polymers, and relevant reports have been increasing in recent years. However, the progress of research on field‐induced imprinted polymers has not been summarized and noticed, resulting in few perspective on the shortcomings and future development of the field‐induced effect which in turn has hindered its further study. Considering this, we firstly introduced the development history and mechanism of imprinted polymers. Then, the field‐induced effects on the mechanism of polymerization and the structure and performances of imprinted polymers were summarized in the order of magnetic field‐induced imprinted polymers, microwave field‐induced imprinted polymers, ultrasonic field‐induced imprinted polymers, electric field‐induced imprinted polymers and high‐energy radiation field‐induced polymers. Significantly, the challenges to the development of field‐induced imprinted polymers were presented, and the development trends of field‐induced imprinted polymers were proposed with the aim to build the bridge for future FI‐IPs research and shed the light on the application research of the field‐induced imprinted polymers. [ABSTRACT FROM AUTHOR]

Background: The use of contact force (CF) sensing catheters has provided a revolutionary improvement in catheter ablation (CA) of atrial fibrillation (AF) in the past decade. However, the success rate of CA for AF remains limited, and some complications still occur. Methods: The TRUEFORCE trial (Catheter Ablation of Atrial Fibrillation using FireMagic TrueForce Ablation Catheter) is a multicenter, prospective, single‐arm objective performance criteria study of AF patients who underwent their first CA procedure using FireMagic TrueForce ablation catheter. Results: A total of 120 patients (118 with paroxysmal AF) were included in this study, and 112 patients included in the per‐protocol analysis. Pulmonary vein isolation (PVI) was achieved in 100% of the patients, with procedure and fluoroscopy time of 146.63 ± 40.51 min and 12.89 ± 5.59 min, respectively. Freedom from recurrent atrial arrhythmia after ablation was present 81.25% (95% confidence interval [CI]: 72.78%–88.00%) of patients. No severe adverse events (death, stroke/transient ischemic attack [TIA], esophageal fistula, myocardial infarction, thromboembolism, or pulmonary vein stenosis) were detected during the follow‐up. Four (4/115, 3.33%) adverse events were documented, including one abdominal discomfort, one femoral artery hematoma, one coughing up blood, and one postoperative palpitation and insomnia. Conclusions: This study demonstrated the clinical feasibility of FireMagic force‐sensing ablation catheter in CA of AF, with a satisfactory short‐ and long‐term efficacy and safety. [ABSTRACT FROM AUTHOR]