Search

Blended wing body(BWB) configuration will be the inevitable trend of the aircraft using in the future civil aviation for its excellent performance. Aerodynamic and flow mechanism investigations of the BWB configuration will provide important support for its design. Wind tunnel tests include force measurements and tuft visualization, in addition to computation fluid dynamics(CFD) simulation, are used to investigate the low speed aerodynamic characteristics and flow mechanism and effects of flow-through nacelles for a 300-passenger BWB configuration(BWB-1). Test results show that longitudinal aerodynamic characteristics of BWB-1 are better than those of the Early BWB or N2A. BWB-1 possesses lateral static stability and directional static instability, however, low value of the directional instability degrades the difficulty in directional stability augmentation and control. Investigation also reveals flow development and physical mechanism of a mild stall characteristic of the configuration. Flow-through nacelles are beneficial to both maximum lift and directional stability, and have minimal effects on lateral stability; however, drag and pitch-down moment are increased. Results from CFD simulation show good agreement with tunnel test data, which demonstrate the validation of the CFD method.

The Map kinase Activating Death Domain containing protein (MADD) isoform of the IG20 gene is over-expressed in different types of cancer tissues and cell lines and it functions as a negative regulator of apoptosis. Therefore, we speculated that MADD might be over-expressed in human breast cancer tissues and that MADD knock-down might synergize with chemotherapeutic or TRAIL-induced apoptosis of breast cancer cells. Analyses of breast tissue microarrays revealed over-expression of MADD in ductal and invasive carcinomas relative to benign tissues. MADD knockdown resulted in enhanced spontaneous apoptosis in human breast cancer cell lines. Moreover, MADD knockdown followed by treatment with TRAIL or doxorubicin resulted in increased cell death compared to either treatment alone. Enhanced cell death was found to be secondary to increased caspase-8 activation. These data indicate that strategies to decrease MADD expression or function in breast cancer may be utilized to increase tumor cell sensitivity to TRAIL and doxorubicin induced apoptosis.

BiFeO3–BaTiO3 is a promising lead-free piezoelectric ceramic, exhibiting high Curie temperature and superior electrochemical characteristics. In this work, (1 − x) BiFeO3–xBaTiO3 (BF–xBT, x = 0. 2 6 , 0.28, 0.30, 0.32, 0.34, 0.36) ceramics were fabricated using the conventional solid-state reaction method through precise composition control. Multiple characterization techniques, including X-ray powder diffraction (XRD), scanning electron microscope (SEM), and electrical property testing systems, were applied to systematically examine the crystallographic structure, microstructure, as well as the dielectric, ferroelectric and piezoelectric properties of the BF–xBT ceramics. The XRD results confirm that all compositions exhibit a typical perovskite structure, transitioning from a single rhombohedral phase to a rhombohedral–cubic phase mixture as the BT content increases. SEM shows apparent core–shell microstructures in the ceramics. Notably, the results demonstrated that the BF–0.30BT ceramic exhibits the maximum piezoelectric constant ( d 3 3 ) ∼ 2 1 7 pC/N, while the BF–0.34BT ceramic displays the maximum converse piezoelectric constant (d 3 3 ∗) ∼ 3 2 3 pm/V, which highlights the suitability of BF–BT ceramics for high-performance piezoelectric applications. [ABSTRACT FROM AUTHOR]

To give consideration to both chip density and device performance, an In0.53Ga0.47As vertical electron–hole bilayer tunnel field effect transistor (EHBTFET) with a P+-pocket and an In0.52Al0.48As-block (VPB-EHBTFET) is introduced and systematically studied by TCAD simulation. The introduction of the P+-pocket can reduce the line tunneling distance, thereby enhancing the on-state current. This can also effectively address the challenge of forming a hole inversion layer in an undoped InGaAs channel during device fabrication. Moreover, the point tunneling can be significantly suppressed by the In0.52Al0.48As-block, resulting in a substantial decrease in the off-state current. By optimizing the width and doping concentration of the P+-pocket as well as the length and width of the In0.52Al0.48As-block, VPB-EHBTFET can obtain an off-state current of 1.83 × 10−19 A/μm, on-state current of 1.04 × 10−4 A/μm, and an average subthreshold swing of 5.5 mV/dec. Compared with traditional InGaAs vertical EHBTFET, the proposed VPB-EHBTFET has a three orders of magnitude decrease in the off-state current, about six times increase in the on-state current, 81.8% reduction in the average subthreshold swing, and stronger inhibitory ability on the drain-induced barrier-lowering effect (7.5 mV/V); these benefits enhance the practical application of EHBTFETs. [ABSTRACT FROM AUTHOR]