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The Ming–Qing transition – the final dynastic change in Imperial China – followed the cyclical patterns of rise and fall that had characterized previous dynastic shifts throughout Chinese history. However, its occurrence in the mid-seventeenth century positions it within a broader context of significant transformations in Europe and the Americas. This transition's most profound impact lay in the culmination of the long-term centralizing processes within Chinese civilization. In its aftermath, the imperial system continued, for a time, to grow stronger, while the economy experienced sustained prosperity driven by both agriculture and commerce. When viewed holistically, this period in Chinese history, while interconnected with European developments, followed a distinct trajectory. Recent scholarship, influenced by the framework of world history, has deepened our understanding of the Ming–Qing transition's role in broader global changes. However, this approach has sometimes led to an overemphasis on international factors, potentially diminishing the transition's significance as a particular phase in China's long-term historical progression. Analyses that predominantly focus on ethnic Manchu–Han dynamics often fail to capture the full historical context. A more nuanced understanding emerges when we examine this period through the lens of the long-term centering process within Chinese civilization. Differences between Chinese and European civilizations extend far beyond comparisons of productive forces. Therefore, discourse around concepts like "convergence" or "divergence" can be misleading without clearly defined comparative frameworks and metrics. [ABSTRACT FROM AUTHOR]

Reducing indium consumption in transparent conductive oxide (TCO) layers is crucial for mass production of silicon heterojunction (SHJ) solar cells. In this contribution, optical simulation‐assisted design and optimization of SHJ solar cells featuring MoOx hole collectors with ultra‐thin TCO layers is performed. Firstly, bifacial SHJ solar cells with MoOx as the hole transport layer (HTL) and three types of n‐contact as electron transport layer (ETL) are fabricated with 50 nm thick ITO on both sides. It is found that bilayer (nc‐Si:H/a‐Si:H) and trilayer (nc‐SiOx:H/nc‐Si:H/a‐Si:H) as n‐contacts performed electronically and optically better than monolayer (a‐Si:H) in bifacial SHJ cells, respectively. Then, as suggested by optical simulations, the same stack of tungsten‐doped indium oxide (IWO) and optimized MgF2 layers are applied on both sides of front/back‐contacted SHJ solar cells. Devices endowed with 10 nm thick IWO and bilayer n‐contact exhibit a certified efficiency of 21.66% and 20.66% when measured from MoOx and n‐contact side, respectively. Specifically, when illuminating from the MoOx side, the short‐circuit current density and the fill factor remain well above 40 mA cm−2 and 77%, respectively. Compared to standard front/rear TCO thicknesses (75 nm/150 nm) deployed in monofacial SHJ solar cells, this represents over 90% TCO reduction. As for bifacial cells featuring 50 nm thick IWO layers, a champion device with a bilayer n‐contact as ETL is obtained, which exhibits certified conversion efficiency of 23.25% and 22.75% when characterized from the MoOx side and the n‐layer side, respectively, with a bifaciality factor of 0.98. In general, by utilizing a n‐type bilayer stack, bifaciality factor is above 0.96 and it can be further enhanced up to 0.99 by switching to a n‐type trilayer stack. Again, compared to the aforementioned standard front/rear TCO thicknesses, this translates to a TCO reduction of more than 67%. [ABSTRACT FROM AUTHOR]

To study the changes in dielectric properties for thermally aged cross-linked polyethylene (XLPE) at different temperatures, the pure thermal and thermal-radiation aging tests are done. Thermal aging is carried at 80℃, 100℃, 135℃ and 155℃, lasting for 100 to 800 hours. The same conditions combined with 100 Gy/h gamma rays are done for thermal-radiation aged samples, and the dielectric spectra are measured from 25 to 200℃. The results show that the activation energy and values of β decrease obviously after the introduction of rays. At the same aging temperature and radiation conditions, electrical conductivity and relaxation peak frequency increase as the increasing aging time, which is a good reflection of dielectric properties during the aging process. Under different temperatures, the deviation in complex permittivity and modulus at lower frequency becomes more distinct compared with the values at a higher frequency. Finally, the dielectric properties under high temperature and low frequency could be a good indicator for the evaluation of XLPE degradation.

Objective: Ankle joint fractures are often accompanied by medial deltoid ligament rupture. There is controversy over whether or how to treat deltoid ligament rupture. This study was aimed to explore the feasibility of repairing the medial deltoid ligament using Kirschner wire internal fixation of the medial tibiotalar joint combined with external fixation. Methods: Forty‐six patients with ankle fractures involving deltoid ligament rupture, treated between October 2012 and February 2021, were retrospectively evaluated. Twenty‐five patients were treated with a Kirschner wire to fix the tibiotalar joint and indirectly repair the deltoid ligament as the repaired group. Twenty‐one patients underwent reduction and fixation of internal and external malleolus fractures, and the deltoid ligament was not repaired in the unrepaired group. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle‐hindfoot score, visual analog scale (VAS), Medical Outcomes Short Form 36‐item questionnaire score (SF‐36), and Medial clear space perpendicular (preoperative, postoperative, final follow‐up) were used for functional evaluations and reduction assessments. Mann–Whitney test were used to compare the differences between the groups. Results: The follow‐up time was 13–112 months with a mean of 59.32 months for the repaired group and 11–94 months with a mean of 53.43 months for the unrepaired group. There was no significant difference in the operative time or intraoperative blood loss between the two groups (p > 0.05). At the last follow‐up, the AOFAS ankle‐hindfoot and SF‐36 scores of the repaired group were significantly higher than those of the non‐repaired group (p < 0.05). Moreover, the VAS pain score was significantly lower and the Medial clear space perpendicular was significantly narrower in the repaired group than that in the unrepaired group. Conclusion: Tibiotalar joint fixation using Kirschner wires is a simple and effective technique that can indirectly reduce and repair the deltoid ligament and stabilize the ankle. [ABSTRACT FROM AUTHOR]

Thin films of transition metal oxides such as molybdenum oxide (MoOx) are attractive for application in silicon heterojunction solar cells for their potential to yield large short‐circuit current density. However, full control of electrical properties of thin MoOx layers must be mastered to obtain an efficient hole collector. Here, we show that the key to control the MoOx layer quality is the interface between the MoOx and the hydrogenated intrinsic amorphous silicon passivation layer underneath. By means of ab initio modelling, we demonstrate a dipole at such interface and study its minimization in terms of work function variation to enable high performance hole transport. We apply this knowledge to experimentally tailor the oxygen content in MoOx by plasma treatments (PTs). PTs act as a barrier to oxygen diffusion/reaction and result in optimal electrical properties of the MoOx hole collector. With this approach, we can thin down the MoOx thickness to 1.7 nm and demonstrate short‐circuit current density well above 40 mA/cm2 and a champion device exhibiting 23.83% conversion efficiency. [ABSTRACT FROM AUTHOR]

Excellent surface passivation induced by (i)a‐Si:H is critical to achieve high‐efficiency silicon heterojunction (SHJ) solar cells. This is key for conventional single‐junction cell applications but also for bottom cell application in tandem devices. In this study, we investigated the effects of (i)a‐Si:H deposition temperature on passivation quality and SHJ solar cell performance. At the lower end of temperatures ranging from 140°C to 200°C, it was observed with Fourier‐transform infrared spectroscopy (FTIR) that (i)a‐Si:H films are less dense, thus hindering their surface passivation capabilities. However, with additional hydrogen plasma treatments (HPTs), those (i)a‐Si:H layers deposited at lower temperatures exhibited significant improvements and better passivation qualities than their counterparts deposited at higher temperatures. On the other hand, even though we observed the highest VOCs for cells with (i)a‐Si:H deposited at the lowest temperature (140°C), the related FFs are poorer as compared to their higher temperature counterparts. The optimum trade‐off between VOC and FF for the SHJ cells was found with temperatures ranging from 160°C to 180°C, which delivered independently certified efficiencies of 23.71%. With a further improved p‐layer that enables a FF of 83.3%, an efficiency of 24.18% was achieved. Thus, our study reveals two critical requirements for optimizing the (i)a‐Si:H layers in high‐efficiency SHJ solar cells: (i) excellent surface passivation quality to reduce losses induced by interface recombination and simultaneously (ii) less‐defective (i)a‐Si:H bulk to not disrupt the charge carrier collections. [ABSTRACT FROM AUTHOR]

At present, “enhancing the sense of acquisition of Ideological and political theory course for postgraduates” has become an inevitable requirement to realize the development of Ideological and political discipline, improve the quality of education and teaching, and implement the mission of moral education. The graduate students’ sense of acquisition of Ideological and political courses is the result of a variety of factors, such as student demand, education supply and external environment. Therefore, by improving the satisfaction of postgraduates to the ideological and political course, enhancing the input of teaching elements and creating the external environment of Ideological and political course teaching, we can strengthen the theoretical and practical significance of education, guide students to adhere to the correct value orientation, and enhance the postgraduates’ sense of acquisition of ideological and political course.