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In order to increase system reliability, it is an economical and efficient method to monitor the defective multichip insulated gate bipolar transistor (IGBT) modules, which are widely used in various high-power electronic systems. A method is presented to monitor chip-branches failure caused by bond-wires defects inside the multichip IGBT modules when the modules are in the off-state. It is based on that the gate input capacitance of the multichip IGBT module will be changed by the failure of chip branches caused by bond-wires defects. The change rate of gate voltage under the constant gate current can be used to characterize the failure. Firstly, according to the gate charge characteristics, the relationship between the change rate of gate voltage and the chip-branches failure under the constant gate current is given. The process of monitoring chip-branches failure is described. Then, a gate driver is presented, which contains a constant current source, and the feasibility of the monitoring method is verified. The study results show that under the constant current source driver and within the specific range of gate voltage, the change rate of gate voltage is independent of temperature and collector–emitter voltage, only related to the failure of chip branches due to bond-wires defects in the multichip IGBT module and increases significantly with the chip-branches failure. Finally, the characteristics of this method are analyzed by comparison with other similar condition monitoring methods. This method is easy to measure and can be applied to the case of real-time and online monitoring.

Abstract Stent graft-induced new entry tear (SINE) is a serious complication in aortic dissection patients caused by the stent-graft itself after thoracic endovascular aortic repair (TEVAR). The stability of SINE is a key indicator for the need and timing of reinterventions. This study aimed to understand the role of hemodynamics in SINE stability by means of computational fluid dynamics (CFD) analysis based on patient-specific anatomical information. Four patients treated with TEVAR who developed a distal SINE (dSINE) were included; two patients had a stable dSINE and two patients experienced expansion of the dSINE upon follow-up examinations. CFD simulations were performed on geometries reconstructed from computed tomography scans acquired upon early detection of dSINE in these patients. Computational results showed that stable dSINEs presented larger regions with low time-averaged wall shear stress (TAWSS) and high relative residence time (RRT), and partial thrombosis was observed at subsequent follow-ups. Furthermore, significant systolic antegrade flow was observed in the unstable dSINE which also had a larger retrograde flow fraction (RFF) on the SINE plane. In conclusion, this pilot study suggested that high RRT and low TAWSS may indicate stable dSINE by promoting thrombosis, whereas larger RFF and antegrade flows inside dSINE might be associated with its expansion.

ObjectiveTo compare our initial perioperative and postoperative outcomes of the modified anterior approach (MA) with Retzius space preservation robot-assisted radical prostatectomy (RARP) with the standard anterior approach (SA) RARP.Materials and methodsA retrospective analysis was performed on 116 patients with RARP completed by the same surgeon between September 2019 and March 2022. They were divided into SA-RARP group (77 cases) and MA-RARP group (39 cases). Propensity score matching was performed using eight preoperative variables, including age, BMI, preoperative PSA, biopsy Gleason score, prostate volume, D’Amico risk classification, SHIM, and clinical T stage. Functional outcome was assessed by urine pad count and SHIM after surgery, and oncological outcome was assessed by statistics of postoperative pathological findings as well as follow-up postoperative PSA. The median follow-up was 13 months and 17 months for MA-RARP and SA-RARP groups respectively.ResultsPropensity score matching was performed 1:1, and baseline data were comparable between the two groups after matching. Comparison of postoperative data: MA-RARP group had less mean EBL than SA-RARP group (200 vs 150 ml, p = 0.033). PSM did not differ between groups (p = 1). In terms of urinary control recovery, the MA-RARP group showed significant advantages in urinary control recovery at 24 h, 2 weeks, 1 month and 3 months after catheter removal, respectively (48.6% vs 5.7%, p < 0.001; 80% vs 22.9%, p < 0.001; 94.3% vs 51.4%, p < 0.001; 100% vs 74.3%, p = 0.002). This advantage gradually disappeared 6 months or more after surgery. The median time to recovery of sexual function was shorter in the MA-RARP group (165 vs 255 d, p = 0.001).ConclusionMA-RARP is safe and reliable, and can achieve better early urinary control function and sexual function recovery while achieving the primary tumor control goal.

All-solid-state batteries (SSBs) are prospective candidates for a range of energy accumulation systems, delivering higher energy densities compared to batteries which use liquid electrolytes. Amongst the numerous solid-state electrolytes (SEs), sulfide-based electrolytes in particular have received more attention given that they have a high ionic conductivity. However, the incompatibility between the electrode and SEs is still an ongoing challenge that leads to poor electrochemical performance. In this work, we focus on 1T-MoS2. It is well known that 1T metallic MoS2 is unstable even at room temperature. However, we showed that 1T-MoS2 can be stabilized at 600 °C for at least 2 h, and the 1T-MoS2-600 interlayer spacing expanded to 0.95 nm. The high crystallinity of the 1T phase is highly compatible with solid electrolytes and coupled with the increased interlayer spacing, so in the all-solid-state lithium-ion battery (ALLLIB), we achieved outstanding cycling performance. At the current density of 0.2 C (1 C = 670 mA g−1), this material delivered a capacity of 406 mA h g−1 after 50 cycles.

The FeNiCr alloys hold application potential in advanced reactors, however, irradiation hardening severely impacts their safety during service. To further enhance the irradiation hardening theory of the FeNiCr alloys, the interaction mechanism between 1/2{111} edge dislocation and 1/3 Frank dislocation loops in the equiproportional multi-principal solid solution Fe33Ni33Cr alloy and the influencing factors were investigated through the molecular dynamics (MD) simulations. Based on the model proposed by Osetsky and Bacon, a face-centered cubic cell with the x, y, and z axes of , , and was constructed with Fe33Ni33Cr as the matrix, and dislocation and dislocation loop were inserted into the cell. By varying the diameter of the dislocation loops and the temperature of the system, the diagram of the interactions and the stress-strain curves were obtained through MD simulation, and the influences of the size of the loops and temperature on the interaction process between the dislocation and dislocation loops were studied. The results indicate that the multi-principal component effect in the Fe33Ni33Cr alloy leads to stress fluctuations during dislocation slip, and the presence of the dislocation loops can cause the dislocation to have a significant stress peak during its slip process, that is, it has a remarkable hindering effect on the dislocation movement, thereby contributing to the irradiation hardening. At the three typical temperatures (300, 600, and 900 K), the critical shear stress of the interaction between the dislocation and dislocation loops is lower at high temperatures than at low temperatures. The reason is that the atomic thermal vibration caused by the temperature increase promotes dislocation motion, and the structural change during the reaction between dislocation and dislocation loops also has a considerable influence on the stress. The interaction between the dislocation and the dislocation loops at 300 K and 600 K is unfault mechanism. In the interaction process, the stacking fault in the Frank dislocation loop disappears and it transforms into a perfect loop, which further enhances the pinning effect of the dislocation loop. Additionally, the effect of dislocation loop size on dislocation slip was studied by comparing the interaction process diagram and the corresponding points on the stress-strain curve. When the diameter of the dislocation loop is 2, 4, and 6 nm, the change of the size of the dislocation loops increases the interaction area between the dislocation and the dislocation loop, and eventually the obstruction ability of the dislocation loop is strengthened. It is worth noting that when the size of the dislocation loop is 2 nm and 4 nm, the interaction leads to generating superjogs, and the generation of new structures increases the resistance of the dislocation to slip freely in the matrix. At the same time, the absorption mechanism which makes new structure increase the stress of the interaction process, resulting in a smaller critical shear stress difference due to the change in the size of the dislocation loops.