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The predeformation prior to artificial aging plays an important role in enhancing the properties of Al–Cu–Li based alloys. This study focused on investigating the impact of a large amount of prerolling (20%) on the orientation variation and distribution characteristics of T1 precipitates in a rolled Al–Cu–Li alloy. The results revealed that T1 phases precipitated in the same orientation were not strictly parallel within a grain, a small angle existed between different phases in the same direction due to the orientation fluctuation of the matrix induced by prerolling. The misorientation degree of the T1 precipitates presented a slight expend tendency with increasing the aging time. Furthermore, the connection between this orientation distortion of the T1 phases and the tensile properties was discussed. Additionally, it was found that the T1 variants along different orientations were heterogeneously distributed, possibly due to the activation of different slip systems during the prerolling process and the variation in the number of nucleation sites among the nonparallel habit planes. [ABSTRACT FROM AUTHOR]

A novel plasmonic waveguide structure consisting of a rectangular resonator side coupled with a split ring resonator (SRR) and a metal–insulator–metal (MIM) waveguide with metal baffle was proposed. The transmission characteristics of the present structure were simulated by a finite-difference time-domain (FDTD) method. The results show that the structure can realize three typical plasmonically-induced reflection (PIR) windows. Meantime, the PIR window can be tuned vertically and horizontally, respectively, and multiple PIR windows with different wavelength intervals can also be obtained by changing the split position. In addition, the sensitivity of the proposed structure can reach up to 1,075 nm/RIU. Furthermore, a rectangular resonator was added to the other side of the plasmonic waveguide structure for realizing the dual-channel PIR window. Another SRR was added to form a symmetrical structure, which further improved the sensitivity and transmittance. Undoubtedly, the proposed structure will have potential applications in sensor and optical switches. [ABSTRACT FROM AUTHOR]

The effects of heat treatment temperature on the microstructure and mechanical properties of Cu0.3Cr2Fe2Ni3Mn2Nbx high-entropy alloys (HEAs) were studied. Results indicate that in the as-cast state, an Nb0 alloy is composed of a single FCC phase, and a Laves phase gradually forms as Nb content increases. After heat treatment at 800 °C, BCC solid solution phases rich in Cr, Fe, and Mn form in all alloys. The BCC phases in the Nb0.2 and Nb0.4 alloys decompose after heat treatment at 900 and 1000 °C, respectively, and the microhardness of the as-cast Cu0.3Cr2Fe2Ni3Mn2Nbx HEAs increases from 127 to 203 HV with increasing Nb content. After heat treatment, the microhardness of the alloys considerably improves, and the Nb0.4 alloy has the highest microhardness after heat treatment at 800 °C (approximately 346 HV). After heat treatment at 900 and 1000 °C, the microhardness of the three alloys decreases. The yield strength of the as-cast Cu0.3Cr2Fe2Ni3Mn2Nbx HEAs increases with Nb content and shows a trend of first increasing and then decreasing with increasing heat treatment temperature. The strengthening mechanism of the heat-treated alloys is mainly attributed to the second-phase strengthening of the Laves phase and the solid solution strengthening of the BCC phase. [ABSTRACT FROM AUTHOR]

This study proposes four kinds of hybrid source–grid–storage systems consisting of photovoltaic and wind energy, and a power grid including different batteries and hydrogen storage systems for Sanjiao town. HOMER-PRO was applied for the optimal design and techno-economic analysis of each case, aiming to explore reproducible energy supply solutions for China's industrial clusters. The results show that the proposed system is a fully feasible and reliable solution for industry-based towns, like Sanjiao, in their pursuit of carbon neutrality. In addition, the source-side price sensitivity analysis found that the hydrogen storage solution was cost-competitive only when the capital costs on the storage and source sides were reduced by about 70%. However, the hydrogen storage system had the lowest carbon emissions, about 14% lower than the battery ones. It was also found that power generation cost reduction had a more prominent effect on the whole system's NPC and LCOE reduction. This suggests that policy support needs to continue to push for generation-side innovation and scaling up, while research on different energy storage types should be encouraged to serve the needs of different source–grid–load–storage systems. [ABSTRACT FROM AUTHOR]

In the external drainage water of Xinjiang Karamay Petrochemical Company, the calcium and magnesium ion contents are as high as 630 mg/L and 1170 mg/L, respectively. These ions are subsequently scaled at large quantities in water treatment equipment, which greatly reduces the efficiency of the process. This study used a coupled chemical precipitation (CP) and electrocoagulation (EC) method to deal with external drainage water. The results show that the removal rates of calcium and magnesium were 94.71% and 96.33%, respectively, when the pH was adjusted with sodium silicate and EC was introduced after saturating the water samples with CO2. In this study, a quadratic polynomial equation was developed for predicting the removal of calcium and magnesium ions using this coupled technique under three factors of current density (CD) (15, 20 and 25 mA/cm2), reaction time (RT) (30, 40 and 50 min) and pH (10.0, 10.5 and 11.0). It was found that these three variables have a significant effect on the removal of both the abovementioned ions. The response surface method based on a Box–Behnken design showed that the average removal rates of calcium and magnesium ions could be 96.57% and 98.66% at a CD of 22 mA/cm2, RT of 46 min and pH of 11. This study confirmed the presence of calcium carbonate in the solid product through XRD and SEM analysis. The results indicate that this study is promising, and the developed technique can also be used to remove the high concentrations of calcium and magnesium ions from different wastewaters. [ABSTRACT FROM AUTHOR]

III-nitride heterostructure-based metal–insulator–semiconductor high-electron-mobility transistors (MIS-HEMTs), compared with Schottky and p-GaN gate HEMTs, have demonstrated significant potential in the next-generation high-power electronic devices due to their exceptional gate reliability. This study presents a comprehensive investigation of threshold voltage (VTH) instability in III-nitride heterostructure-based MIS-HEMTs, with a specific emphasis on the interfaces of the multi-heterostructures. Two widely studied amorphous materials, namely, Al2O3 and SiNx, have been extensively examined as primary gate insulators in GaN-based MIS-HEMTs. To efficiently remove native oxides from the (Al)GaN surface, a novel in situ high-temperature remote plasma pretreatment (RPP) technique has been developed. This technique involves sequential application of NH3/N2 plasmas on the (Al)GaN surface before depositing the gate insulators using plasma-enhanced atomic layer deposition. The remarkable RPP process has proven to be a highly effective method for revealing atomic steps on the GaN surface, irrespective of whether the surface has undergone oxidation or etching processes. To further enhance the interface quality and potentially reduce bulk traps in the gate insulator, optimization of deposition temperature and post-deposition annealing conditions have been explored. Additionally, an electron-blocking layer, such as SiON, is incorporated into the MIS-HEMTs to prevent electron injection into bulk traps within the insulator. Novel characterization techniques including constant-capacitance and isothermal-mode deep-level transient spectroscopy have also been developed to explore the failure mechanisms in MIS-HEMTs. These techniques allow for the differentiation between bulk traps in the GaN epitaxy and those present within the gate insulators. This in-depth physical understanding provides valuable insights into the sources of failure in GaN-based MIS-HEMTs. [ABSTRACT FROM AUTHOR]

Krüppel‐like factor 13 (KLF13), a zinc finger transcription factor, is considered as a potential regulator of cardiomyocyte differentiation and proliferation during heart morphogenesis. However, its precise role in the dedifferentiation of vascular smooth muscle cells (VSMCs) during atherosclerosis and neointimal formation after injury remains poorly understood. In this study, we investigated the relationship between KLF13 and SM22α expression in normal and atherosclerotic plaques by bioanalysis, and observed a significant increase in KLF13 levels in the atherosclerotic plaques of both human patients and ApoE−/− mice. Knockdown of KLF13 was found to ameliorate intimal hyperplasia following carotid artery injury. Furthermore, we discovered that KLF13 directly binds to the SM22α promoter, leading to the phenotypic dedifferentiation of VSMCs. Remarkably, we observed a significant inhibition of platelet‐derived growth factor BB‐induced VSMCs dedifferentiation, proliferation, and migration when knocked down KLF13 in VSMCs. This inhibitory effect of KLF13 knockdown on VCMC function was, at least in part, mediated by the inactivation of p‐AKT signaling in VSMCs. Overall, our findings shed light on a potential therapeutic target for treating atherosclerotic lesions and restenosis after vascular injury. [ABSTRACT FROM AUTHOR]

To investigate the impact of combining aluminum sulfate with straw and irrigation water to enhance soil quality in soda saline–alkali soil, in this study a field experiment was conducted in Tongliao City, Inner Mongolia Autonomous Region, China. With beet IM1162 as the indicator crop, four levels of aluminum sulfate dosage (30, 60, 90, 120 g m−2) and four levels of drip irrigation water quota (225, 270, 315, 360 m3 ha−1) were set. The study examined the impact of varying levels of aluminum sulfate and irrigation water on soil water salt and crop yield. Next, using a comprehensive evaluation method, the optimal quantities of aluminum sulfate and irrigation water needed for effective soil improvement were determined. The research findings indicate that the most effective treatment (W2S3) involved an aluminum sulfate dosage of 90 g m−2 and an irrigation quota of 270 m3 ha−1. This treatment resulted in significant improvements compared to the control (CK) group. Specifically, in the 0–50 cm soil layer, the following improvements were observed: the water storage capacity (SWS) increased by 51.7%; evapotranspiration (ET) increased by 16.2%; water use efficiency (WUE) increased by 55.0%; and irrigation water use efficiency (IWUE) increased by 98.1% (p < 0.05). These results emphasize the importance of optimizing the combination of aluminum sulfate dosage and irrigation water quota to improve soil conditions and crop performance. It is worth nothing that this study highlights the potential for enhancing water use efficiency and crop yield in agricultural practices, which can contribute to sustainable and efficient farming practices. The study results revealed significant improvements in soil quality and crop yield when compared to the control group (CK). Specifically, in the 0–50 cm soil layer: the soil salt content decreased by 19.8%, soil pH increased by 8.7%, and exchangeable sodium percentage (ESP) decreased by 34.0%. Moreover, the crop yield in the treatment group increased significantly, by 32.1%. These findings indicate the positive impact of the intervention on soil health and agricultural productivity. The study employed the game theory combination weighting method to comprehensively evaluate soil water, salt, and various yield indicators. The results showed that the sustainability weight for crop yield reached 0.116, emphasizing the aim of soil improvement: the sustainable enhancement of crop yield. This approach underscores the importance of balanced soil management practices to ensure long-term agricultural productivity and environmental sustainability. The comprehensive evaluation results of grey relation analysis and the TOPSIS coupling model showed that the soil improvement effect score was the highest when the dosage of aluminum sulfate was 61.7–120.0 g m−2, and the irrigation quota was 250.4–319.4 m3 ha−1, which was the recommended range for the local area. The research findings discussed in the provided sources contribute to the theoretical basis for soil improvement in soda–saline–alkali land. [ABSTRACT FROM AUTHOR]

The ultrathin‐barrier (UTB) AlGaN/GaN heterostructure exhibits great promise as a technology for manufacturing high‐performance normally OFF GaN metal–insulator–semiconductor high‐electron‐mobility transistors (MIS–HEMTs) due to its unique gate recess‐free feature. However, a critical challenge in UTB MIS–HEMTs is the recovery of the 2D electron gas in the access region, particularly with regard to achieving low ON resistance. In this study, a new approach is proposed to address this issue by utilizing a low‐thermal‐budget Al2O3 film grown through atomic layer deposition (ALD). By analyzing the capacitance–voltage characteristic and correlating it with the threshold voltage shift versus dielectric thicknesses for SiNx and Al2O3, high density of positive fixed charges (≈2.382 × 1013 cm−2) is confirmed to be induced at the interface between ALD–Al2O3 and GaN (cap), which is also in good agreement with 1D Poisson simulations of energy band diagrams. The positive charges are probably originated from the interface AlAl bonds revealed by X‐Ray photoelectron spectroscopy analysis. [ABSTRACT FROM AUTHOR]

Objective: Complications or serious adverse events (SAEs) are common in the treatment of patients with large vessel occlusion stroke. There has been limited study of the impact of SAEs for patients after endovascular thrombectomy (EVT). The goal of this study was to characterize the rates and clinical impact of SAEs following EVT., Methods: A post hoc analysis was performed using pooled databases of the "DEVT" and "RESCUE BT" trials. SAEs were designated as symptomatic intracranial hemorrhage, brain herniation or craniectomy, respiratory failure, circulatory failure, pneumonia, deep venous thrombosis, and systemic bleeding. The primary endpoint was functional independence (modified Rankin scale score 0-2 within 90 days). Logistic regression analysis was used to determine the predictors and associations between SAEs and outcomes., Results: Of 1,182 enrolled patients, 402 (34%) had a procedural complication and 745 (63%) had 1,404 SAE occurrences with 4.65% in-hospital mortality. The three most frequent SAEs were pneumonia (620, 52.5%), systemic bleeding (174, 14.7%), and respiratory failure (173, 14.6%). Pneumonia, systemic bleeding, or deep venous thrombosis was less life-threatening. Patients with advanced age (adjusted odds ratio, 1.28 [95% confidence interval, 1.14-1.43]), higher NIHSS (1.09 [1.06-1.11]), occlusion site (middle cerebral artery-M1 vs. internal carotid artery [ICA]: 0.75 [0.53-1.04]; M2 vs. ICA: 1.30 [0.80-2.12]), longer procedure time (1.01 [1.00-1.01]), and unsuccessful vessel recanalization (1.79 [1.06-2.94]) were more likely to experience SAEs. Compared with no SAE, patients with SAEs had lower odds of functional independence (0.46 [0.40-0.54])., Conclusions: Overall, SAEs diagnosed following thrombectomy in patients with stroke were common (more than 60%) and associated with functional dependence. Patients with advanced age, higher NIHSS, longer procedure time, and failed recanalization were more likely to experience SAEs. There was no statistical difference in the risk of SAEs among patients with M1 and M2 occluded compared with those ICA occluded. An understanding of the prevalence and predictors of SAEs could alert clinicians to the estimated risk of an SAE for a patient after EVT., (© 2024 S. Karger AG, Basel.)