Hengyang Normal University

About: Hengyang Normal University is a education organization based out in Hengyang, China. It is known for research contribution in the topics: Graphene & Adsorption. The organization has 1087 authors who have published 1280 publications receiving 13850 citations. The organization is also known as: Hengyang Teachers' College & Héngyáng Shīfàn Xuéyuàn.

Research on the lower detection efficiency of the RAD7 for 220Rn than for 222Rn

Abstract: The measurement sensitivity of the RAD7 to the 220Rn concentration in its internal cell is 30% less than the sensitivity to 222Rn. This reduction in 220Rn sensitivity relative to 222Rn sensitivity has been attributed to the decay of 216Po before it reaches the collection electrode. Analyzing the airflow patterns in the internal cell of RAD7, we propose that this may also be due to a ``short-circuit stream" — highly concentrated 220Rn injected into the internal cell and discharged from another port quickly. Since in the ``short-circuit stream'', the 220Rn concentration of outflow is high, the 220Rn concentration remaining in the internal cell must be low. Therefore, further improvement to the reliability and accuracy of 220Rn measurements may be attained by the improvement of the measuring chamber geometric factor and the electric field.

On Klein-Maskit combination theorem in space II

Abstract: In this paper, which is sequel to [10], we give a generalisation of the second Klein-Maskit combination theorem, the one dealing with HNN extensions, to higher dimension. We give some examples constructed as an application of the main theorem.

The hot corrosion behavior in vanadate environment and thermal cycling behaviors of YTZ and 2GYTZ for thermal barrier coating applications

Abstract: A preliminary examination was carried out for hot corrosion resistance to V2O5 and thermal cycling behaviors of two alternative materials: zirconia co-doped with 16 mol% YO1.5 + 16 mol% TaO2.5 (YTZ) and zirconia co-doped with 14 mol% YO1.5+ 2 mol% GdO1.5 + 16 mol% TaO2.5 (2GYTZ). The compositions and microstructures of the samples were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). Results showed ZrV2O7 and YVO4/GdVO4 were the main reaction products at 750 °C and 850 °C for 2 h, while YVO4 and m-ZrO2 were detected as the main corrosion products at 850 °C for 10 h or rising temperature to 950 °C. With the depletion of V2O5, ZrV2O7 disappeared and decomposed into m-ZrO2 and V2O5. The hot corrosion mechanisms are similar for YTZ and 2GYTZ ceramics. However, the amount of m-ZrO2 in the 2GYTZ was much more than that in the YTZ at the same corrosion conditions. The weaker bonds due to partial substitution of Y3+ with larger size of Gd3+ and the size misfit between Gd3+ and Zr4+ resulted in decreasing the anti-corrosion capability of 2GYTZ ceramic. The tetragonal phase was very stable for YTZ and 2GYTZ coatings during high temperature heat treatment. The thermal durability of the YTZ and 2GYTZ TBCs can be significantly improved by using the YSZ buffer layer. While the cycling lifetimes for 2GYTZ coating was much shorter than that of YTZ coating whether designed for single-ceramic-layer structure or double-ceramic-layer structure. Failure of the 2GYTZ coating mainly resulted from the thermal expansion mismatch stress, concentrated thermal stress introduced by the severe sintering and low fracture toughness.

Application of audio visual tuning detection software in piano tuning teaching

Abstract: Nowadays, the development of electronic technology is changing every day. Computer technology has been widely used in various fields; therefore piano tuning teaching needs to keep pace with the social pace, and the tuning industry needs to be updated and explored to make it step on a new stage. In this study, the Fast Fourier Transform, Auto-correlation and Cepstrum feature extraction algorithms for audio visualization software were used to extract and visualize the audio features of seven piano tones from G4 to A4, and according to the characteristics the frequency was calculated and contrasted with the standard audio. Through the sound visualization analysis, it was found that the Auto-correlation algorithm was more consistent with the standard frequency. The use of sound visual tuning detection can plays an auxiliary role in piano tuning teaching.