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On the turbocharger, two forms of intake pipe, bending and torsion, are usually used, which leads to a vortex at the inlet of the blade. It has been found that double vortices and massive vortices play a significant role in the working characteristics of the compressor. This project intends to conduct a systematic theoretical and experimental study on the effects of vortex deformation under two different working conditions of bending and torsion on the internal flow field, tip leakage flow field, and impeller load of the impeller. It has been found that the presence of a vortex near the blade entrance changes the static pressure and inflow angle near the blade entrance. The reverse transfer of vortex flow and vortex flow caused by vortex has three critical effects on the working characteristics of the compressor: 1. The change of circumferential static pressure and the pressure gradient of the flow in the impeller. 2. The location and density of the leakage flow on the top surface are significantly changed. 3. Adjust the impeller load’s change and fluctuation when it rotates.

The geometry of the vortex shell significantly affects the non-axisymmetric flow in centrifugal compressors. This study explores the static pressure characteristics of the vortex shell through experimental data and numerical analysis using finite element software. Findings indicate that the vortex tongue region critically influences the cascade structure. At high flow rates (0.40 kg/s), flow field parameters at the blade and vortex shell inlets alter markedly near the tongue side. Conversely, at lower velocities (0.26 kg/s), flow distribution at the blade inlet becomes more uneven, and changes in the inflow angle are more pronounced. Additionally, blade pulsation intensifies at higher velocities, and the jet wake vortex exhibits structural variations at different velocities. High-pressure fluctuations are notably transmitted upwards through the vortex shell, with periodic fluctuations affecting the impeller load. These changes significantly impact the flow field under various operating conditions.

Creep characterization of different diameter silica bar core during directional solidification of the single crystal superalloy was investigated by suspension method. The scanning electron microscope (SEM) was employed to observe the microstructure of the surface and transversal section of crept silica bar. The energy dispersive spectroscopy (EDS) and X-ray diffraction technology were used to analyse and determine the composition of the reaction product. The experimental results show that the crept deformation amount increases with prolonging of creep time and decreasing of the diameter of the silica bar. When the creep time is 60 min, the diameter 0.5 mm silica bar has the largest creep deformation, and the average deformation is 30 mm, while the 2 mm silica bar is 24 mm. The interfacial reaction of SiO2 with C and Al, which are deposited on the silica bar surface due to the elevated temperature and low vacuum, induces the formation of porous layer. The volume fraction of the porous reaction products leads to the different crept deformation amount of different diameter silica bars. The creep deformation amount of silica bars has a linear relationship with the volume fraction of surface reaction products.

Study region: This study focuses on the upper reaches of Shule river (URSLH) and Heihe river (URHH) basins and Taolai river (URTLH) basin in Qilian Mountains. Study focus: The impact of the cryosphere changes on runoff components in basins with different cryosphere ratios. New hydrological insights for the region: Total runoff (TR) increased in URSLH and URHH and decreased in URTLH, snowmelt runoff (SR) decreased in each basin, glacier runoff (GR) increased in URSLH and URTLH but decreased in URHH during 1980–2015. In the future, GR will increase under SSP585 and slightly decrease under SSP126 in 2040–2060 in URSLH and decrease in URHH and URSLH. The peak time of SR will advance by a month in each basin. In the future, GR (The ratio of the coefficient of variation (cv) of TR to cv of non-glacial runoff) will decrease, indicating hydrological regulation of glaciers will be weakened in these basins. SR and Rs (The ratio of summer runoff to spring runoff) will show downward trends, the processes of TR increase will be smoother. Rr (The ratio of maximum to minimum monthly runoff) will show downward trends under SSPs. TR will become smoother in each basin. Furthermore, the change of each runoff components will make TR tends to be smoother in the future and reduce TR especially in summer.

Domestic tourism demand has dominated the global tourism market and has been more resilient during the COVID-19 pandemic; yet, it is under-studied compared to international tourism demand. Digital financial inclusion (DFI) enables the provision of formal financial products and services to small and medium-sized tourism enterprises and tourists through cost-effective digital means, potentially boosting domestic tourism demand. Integrating micro- and macro-level data from 335 prefecture-level regions in China, we investigate the impact of DFI on domestic tourism demand using spatial panel models. Our analysis reveals significant and positive effects, both direct and spillover, of DFI on domestic tourism demand within a region and across regions. Notably, among the three dimensions of DFI, the usage depth exhibits the most substantial spillover effects. Furthermore, our findings also highlight the crucial role of DFI in internalizing domestic tourism revenues. Our study provides practical implications for sustainable domestic tourism development in the digital era. [ABSTRACT FROM AUTHOR]

The Yellow River Delta wetland is a habitat for wintering waterfowl, where mallard (Anas platyrhynchos) and tundra bean goose (Anser fabalis) are commonly observed. Although the intestinal flora plays a pivotal role in maintaining host health and promoting nutrient absorption, it remains unclear whether the same overwintering habitat and challenging feeding conditions specifically affect the composition and diversity of intestinal flora in both species. Here, high-throughput sequencing was used to compare the intestinal bacterial communities of mallard and tundra bean goose from the same region. There was no significant difference in alpha diversity and beta diversity between the two species. Firmicutes and Proteobacteria were the two predominant phyla, accounting for more than 50.00% of the total. They enhanced the nutrient absorption and metabolic efficiency during overwintering. Catellicoccus was the most dominant genus in the intestinal flora of tundra bean goose, accounting for 33.91%, whereas Clostridium sensu stricto 1 was the most dominant genus in mallard, accounting for 7.34%. This difference is considered to be related to the feeding habits of these two species. No significant differences in the structure and diversity of intestinal bacterial communities were observed between mallard and tundra bean goose, and the similarity of intestinal flora between them was high. This study deepens our understanding of the intestinal flora of two coexisting species with different dietary preferences in the Yellow River Delta. It also lays the foundation for waterfowl disease prevention in this area, carrying significant scientific and practical implications for biodiversity and ecosystem conservation. [ABSTRACT FROM AUTHOR]

An ultra-high-speed electric air compressor (UHSEAC) generates a load torque component during operation, leading to unstable output. As air passes through the UHSEAC, the air density changes significantly, resulting in increased uneven distribution. This causes rapid changes in gas parameters, making them difficult to extract. Consequently, the behavior of load torque component variations under ultra-high-speed operating conditions (UHSOC) remains unclear. The influence of UHSOC on the load torque component has not been studied. In this article, the fluid model of the UHSEAC is established and verified, and the load torque component is extracted based on this model. The influence of speed and torque on the load torque component under UHSOC is then studied. The results show that the frequency of the load torque component increases by 14.29% as the speed increases from 70,000 rpm to 90,000 rpm. Additionally, as the torque increases from 1.3 Nm to 1.7 Nm, the amplitude of the load torque component increases by 69.56%. These findings provide valuable guidance for future scholars seeking to optimize UHSEAC design to reduce load torque components. [ABSTRACT FROM AUTHOR]

Recently, low efficiency and stability due to unbalanced carrier injection remain urgent problems in inorganic quantum dot light†emitting diodes (QLEDs). To address these issues, the device was irradiated with ultraviolet light in this study, which improved the interface contact. This resulted in the smaller electron potential barrier, increased hole injection and more balanced carrier injection in the device. Ultimately, the device efficiency was improved, and the operating lifetime of the device was increased by ~91†fold. [ABSTRACT FROM AUTHOR]

In this work, efficient QD‐photosensitive ligand system were designed. By direct photolithography, RGB pixel arrays with a single sub‐pixel size of 39 um × 5 um were successfully prepared on patterned PM substrates. While illuminated separately, there were no residual QD emission peaks from neighbor sub‐pixel in electroluminescence spectra. Experience on the PM substrate guided the successful preparation of a 4.7‐inch 650 ppi AM‐QLED display. This was the first AM‐QLED prototype prepared by direct lithography. [ABSTRACT FROM AUTHOR]

In this paper the photolithgraphic patterning approaches of quantum dots in electroluminescent devices and demoes were summerized. Photolithograpy process meets the requirements for QLED mass production, including high pixel density, large‐area process and low cost. We summerized three approaches of quantum dot photolithographic procrsses, including direct photolithography, photolithography with lift‐off process and sacrificial layer assisted patterning (SLAP). [ABSTRACT FROM AUTHOR]