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The horizontal (L/D) and vertical H / D ) spacing ratios of square bluff bodies are critical parameters influencing the efficiency of vortex-induced vibration (VIV) wind energy harvesting. This study investigates a tandem stationary square bluff body (SSBB) and a vibrating square bluff body under various spacing configurations using ANSYS/FLUENT simulations. The results show that without SSBB, the root-mean-square (RMS) voltage generated by the piezoelectric patches increases consistently with wind speed. However, with SSBB, RMS voltage initially decreases and then increases as L/D rises, reaching a minimum at L/D = 4.5. At optimal configurations (L/D = 6.5, H/D = 0.5) and a wind speed of 9 m/s, the RMS voltage achieves a maximum value, improving by 34.43% compared to the configuration without SSBB. Experimental validation confirms the simulation results. This finding will be a significant fundamental for future design of VIV wind energy harvesting devices. [ABSTRACT FROM AUTHOR]

Ternary system piezoelectric ceramics 0.7PbZrxTi1−xO3-0.3Pb(Zn1/3Nb2/3)O3 (abbreviated as 0.7PZTx-0.3PZN) were prepared by a traditional solid-phase process. With the increase in Zr content, the electrical properties of the ceramics were significantly improved, and this result could be attributed to the change in the ceramic phase structure. The relationship between the change in Zr content and the ceramic phase structure and properties was investigated in detail by component modulation. X-ray diffraction (XRD) analyses showed that the phase structure of the ceramics undergoes a transition from the coexistence of tetragonal (T) and rhombohedral (R) phases to the predominance of rhombohedral (R) phases as the Zr content x increases. The phase structure of the ceramics at x = 0.49 is closer to the morphotropic phase boundary (MPB), with about 32% of the T-phase and 68% of the R-phase, and possesses good electrical properties: d33 = 483 pC/N, kp = 0.69, εr = 2171.7, tanδ = 0.016, Tc = 292.5°C, Pr = 35.9 μC/cm2, Ec = 7.7 kV/mm. Constructing the MPB of 0.7PZT-0.3PZN piezoelectric ceramics by varying the Zr content can be effective in improving the electrical properties and understanding more broadly how the change in Zr/Ti composition affects the piezoelectric behavior. [ABSTRACT FROM AUTHOR]

In the preparation of (Ba,Ca)(Zr,Ti)O3 lead-free piezoelectric ceramics, different Ca2+ and Zr4+ contents will greatly affect the phase structure, microstructure, and electrical properties of the ceramics. XRD shows that all samples have pure perovskite phase structure, and the (Ba0.85Ca0.15)(ZryTi1−y)O3 ceramics morphotropic phase boundary region from tetragonal phase to rhombohedral phase near 0.08 ≤ y ≤ 0.1. From the dielectric temperature curve, the phase transition temperature (TO-T) was found near room temperature at 0.12 ≤ x ≤ 0.18 for the (Ba1−xCax)(Zr0.1Ti0.9)O3 ceramics. Both Ca2+ and Zr4+ increase have a significant decrease on the Curie temperature Tc. All samples were revealed as relaxers with diffusivities in the range 1.29 ≤ γ ≤ 1.82. Different from the undoped ceramics, ceramics doped with Ca and Zr ions exhibit saturated P–E hysteresis loops, and their ferroelectric properties are significantly optimized. In particular, the (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 ceramic demonstrated optimal properties, namely d33 = 330 pC/N, kp = 0.41, εr = 4069, Pr = 4.8 μC/cm2, and Ec = 3.1 kV/cm, indicating that it is a viable lead-free piezoelectric contender. Variations in Ca and Zr content have a significant effect on the crystal grain sizes and densities of ceramics, which is strongly associated with their piezoelectricity. [ABSTRACT FROM AUTHOR]

Zirconia ceramics are widely used in aerospace, precision machinery, electronics, and biomedical fields because of their high temperature resistance, wear resistance, strong electromagnetic response, and biocompatibility. Nevertheless, high brittleness and low shear strength seriously hinder the large-scale application of zirconia ceramics in industrial production. This paper mainly reviews the research advances on primary machining technologies of zirconia ceramics from two aspects. One aspect is traditional machining of zirconia ceramics, which primarily focuses on the issues such as tool wear, machined surface quality, and cutting force in milling and grinding of zirconia ceramics. And the other aspect is non-traditional machining of zirconia ceramics, which primarily focuses on material removal rate and machined surface quality of zirconia ceramics using the electrical discharge machining (EDM) by assisting electrode method. The machinability and machining quality of zirconia composite ceramics by EDM with the adding conductive phase method have also been analyzed. Furthermore, for the auxiliary machining methods, the effects of ultrasonic vibration-assisted machining (UVAM) and laser-assisted machining (LAM) of zirconia ceramics are comparatively analyzed and elaborated. Subsequently, the research progress of traditional and non-traditional machining of zirconia ceramics is summarized and discussed. Finally, different machining methods of zirconia ceramics were prospected, and their future development trends were discussed, which provides a reference for further improving the machining efficiency and accuracy of zirconia ceramics. [ABSTRACT FROM AUTHOR]

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Antitumor effects obtained by autologous Lewis lung cancer cell vaccine engineered to secrete mouse interleukin 27 by means of cationic liposome. Correction to: Cellular immunotherapy using irradiated lung cancer cell vaccine co-expressing GM-CSF and IL-18 can induce significant antitumor effects. [Extracted from the article]

Brassinolide (BR) is the "sixth class" plant hormone, which plays an important role in various physiological and biochemical processes of plants. The wide variety of functions of Pinellia ternata means that there is huge demand for it and thus it is in short supply. This paper mainly assessed the changes of yield and quality in P. ternata at different stages after BR treatments by principal component analysis, in order to improve the yield and quality of P. ternata and at the same time determine the best harvest time. The results showed that the tuber yield of P. ternata was significantly increased by BR treatments at different stages (except for the 15th day). After the 15th, 45th, 60th, 75th, 90th, and 105th day of treatments, the tuber yield of P. ternata reached peak values at 0.10 (0.65 g), 0.50 (1.97 g), 0.50 (1.98 g), 1.00 (2.37 g), 1.00 (2.84 g), and 2.00 mg/L (3.76 g) BR treatment, respectively. The optimal harvest time was the 75th day after 0.10, 0.50, and 1.00 mg/L BR treatments, which not only significantly improved the yield of P. ternata, but also retained high level of total alkaloids in the tubers (20.89, 5.37, and 13.44%) and bulbils (9.74, 20.42, and 13.62%), high total flavone content in the tubers (17.66, 16.26, and 12.74%) and bulbils (52.63, 12.79, and 38.69%), and high β-sitosterol content in the tubers (25.26, 16.65, and 0.62%) of P. ternata, compared with the control, respectively. [ABSTRACT FROM AUTHOR]