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This research investigates the complex temperature distribution and fatigue behavior of single film-cooling holes manufactured by lasers with different pulse widths in a real flow field. The aerodynamic and heat transfer characteristics of film-cooling holes manufactured using lasers with different pulse widths were analyzed through laser drilling experiments, conjugate heat transfer simulations, and crystal plasticity finite element methods. The study investigated the relationship between changes in the geometric accuracy of the film-cooling holes and the corresponding flow and temperature fields during the film-cooling process. Additionally, the effects of temperature and structural variations on the stress around the holes in a flat plate composed of the second-generation nickel-based single-crystal superalloy DD6 in real flow and temperature fields were studied. The coupling effect of the temperature and stress fields around the holes on the fatigue behavior of the film-cooling holes was examined, and the fatigue damage mechanism of film-cooling holes in complex temperature fields was analyzed. It was found that changes in the blowing ratio do not affect the temperature and stress distributions around the holes but only alter the temperature peak. An increase in the temperature peak results in a decrease in the stress peak. Additionally, the fatigue damage of single film-cooling holes is determined by both the structural defects of the holes and the changes in material behavior due to the temperature around the holes, with the structural influence being more significant. [ABSTRACT FROM AUTHOR]

Cone‐beam computed tomography (CBCT) system can provide real‐time 3D images and fluoroscopy images of the region of interest during the operation. Some systems can even offer augmented fluoroscopy and puncture guidance. The use of CBCT for interventional pulmonary procedures has grown significantly in recent years, and numerous clinical studies have confirmed the technology's efficacy and safety in the diagnosis, localization, and treatment of pulmonary nodules. In order to optimize and standardize the technical specifications of CBCT and guide its application in clinical practice, the consensus statement has been organized and written in a collaborative effort by the Professional Committee on Interventional Pulmonology of China Association for Promotion of Health Science and Technology. [ABSTRACT FROM AUTHOR]

[Ca24Al28O64]4+(4e−) (C12A7:e−) has excellent potential in electric propulsion owing to various advantages, including low work function, low working temperature, and stable chemical properties. However, increasing electron concentration enhances the thermionic emission property of C12A7:e−. This study used a chemical method—spark plasma sintering to synthesize Zr‐doped C12A7:e− (C12(A1 −xZx)7:e−, where x = 0 to 0.14). The study results show that C12(Al0.86Zr0.14)7:e− maximum injected electron concentration (n), conductivity (σ), electron mobility (μn), and zero‐field emission current density (Jo) improved to 2.4 × 1021 /cm3, 1507 S/cm, 5.2 cm2/V·s, and 2.4 A/cm2, respectively. The emission current density of the C12(Al0.86Zr0.14)7:e− could be maintained at about 2.9 A/cm2 under 1100°C, 4000 V, and 600 min. Theoretical calculation results prove that Zr doping broadens the cage conduction band (CCB) of C12A7:e− and reduces the bandgap between the CCB and the frame conduction band. In addition, Zr doping increases the electronic density of states near the Fermi level, and the density of states presents a continuous state. This helps to increase the injected electron concentration and enhance the electrical transport and thermionic emission characteristics of the sample. The calculation results provide theoretical support for the experiment. [ABSTRACT FROM AUTHOR]

(Ca1‐xCux) 12A7: e– bulks (0 ≤ x ≤ 0.05) with electrical performance were fabricated by the in‐situ aluminothermic synthesis. The results showed that all the electron concentrations of (Ca1‐xCux) 12A7: e– reached the theoretical value of about 2.28 × 1021 cm–3. In (Ca0.96Cu0.04) 12A7: e–, the electron mobility at room temperature increased from 3.81 to 5.19 cm2 V–1 S–1 and the conductivity increased from 415 to 1405 S cm–1. It indicated that Cu‐doping effectively improved electrical properties. The photoexcitation property also changed positively. The energy required for electrons to transition from cage conduction band to frame conduction band showed a decreasing trend, from 2.23 to 1.48 eV. The first‐principle calculation showed an upward shift in the Fermi energy level position of C12A7: e–. In addition, Cu atoms provided more density of states near the Fermi energy level. The number of empty orbitals near the Fermi surface of (Ca1‐xCux) 12A7: e– that can receive excited electrons increased. It provided a theoretical basis for preparing (Ca1‐xCux) 12A7: e– with high electrical transport characteristics. [ABSTRACT FROM AUTHOR]

The [Ca24Al28O64]4+:4e− (C12A7:e−) electride is a conductive oxide ceramic with high injected electron concentration and low work function, but its brittleness leads to difficulty in mechanical processing and low production yield. The present work aimed at improving the mechanical properties of C12A7:e− by introducing monoclinic ZrO2. When the ZrO2 content was 5 wt%, the fracture toughness increased 133% from 1.819 to 4.214 MPa m1/2 and the flexural strength increased 116% from 15.916 to 34.469 MPa for C12A7:e−-5 wt% ZrO2, indicating that ZrO2 can effectively improve the mechanical properties of C12A7:e−. The microstructure and phase analysis showed that the toughening mechanisms of ZrO2 composite C12A7:e− contain both stress-induced phase transformation toughening and dispersion toughening of ZrO2 particles. When the content of ZrO2 is between 0 and 5 wt%, the injected electron concentration of C12A7:e−-ZrO2 was maintained in the range of 2.05–2.10 × 1021 cm−3 and illustrate excellent electrical transport properties. The study indicated that adding ZrO2 in C12A7:e− effectively solves the problem of brittle fracture, improves the finished product rate during processing, and maintains its excellent electrical transport properties. [ABSTRACT FROM AUTHOR]