Ahmet Fatih Isik  Nalan Oya San Keskin  Yusuf Ulcay 《纺织学会志》2019,110(4):575-580

Polyvinyl alcohol (PVA) electrospun nanofibers and boric acid (BA) complexes of these nanofibers were synthesized with and without using TritonX-100(TX-100) as a water soluble surfactant (PVA, PVA/BA, PVA/TX-100, PVA/TX-100/BA). The electrospun nanofibers were characterized by SEM, FTIR and TGA. Preliminary results showed that certain amount of boric acid decreased the number of Stapylococcus aureus from 6,8x10⁷(CFU/mL) to 3x10⁷(CFU/mL). In the preparation of polymer, boric acid was used as a crosslinker and antimicrobial agent whereas TX-100 was used as surfactant. The viscosity and conductivity measurements indicated that the BA increased viscosity but decreased conductivity. In contrast, TX-100 increased conductivity without considerable effect on viscosity, which affects the production and resulting nanofiber properties such as diameter and bead formation. The antimicrobial activities of the nanofibers were assayed in vitro by Gram-negative (E. coli) and Gram-positive(S. aureus) bacteria. It was observed that PVA/TX-100/BA showed better antibacterial activity against S.aureus bacteria compared to PVA and PVA/TX-100 nanofibers.  相似文献   

    

Guangfan Tan  Xin Hu  Liang Cai  Haifeng Xue  Yasuhisa Oya  Yingchun Zhang 《International Journal of Applied Ceramic Technology》2023,20(4):2562-2575

The tritium breeder and structural materials are necessary components in the blanket to realize tritium (T) self-sustainment of nuclear fusion. The long-term exposure between tritium breeders and structural materials will cause surface corrosion in irradiation environments and then further affect the tritium release behavior. In this study, chemical compatibility between Li₂TiO₃ ceramic pebbles and advanced structural materials was studied systematically at 700 °C for 300 h under He+0.1 % H₂ environment, respectively. The color of the Li₂TiO₃ ceramic pebbles changes from white to dark grey and black. Moreover, the grain size of Li₂TiO₃ ceramic pebbles increases to more than 5 μm, and the crushing load decreased slightly. For the structural materials, the Al-rich oxide layer with about 188.7 nm of 14Cr-5Al oxide dispersion strengthened (ODS) steel and Cr-Fe rich oxide layer with about 1.04 μm of 14Cr-ODS steel were observed on the cross-section. The effective diffusion coefficient of O element in Li₂TiO₃ ceramic moved into ODS steel at 700 °C was calculated to be 3.3 × 10⁻¹⁶cm²/s and 1.02 × 10⁻¹⁴ cm²/s. Unfortunately, when SiC ceramics were contacted with the pebbles, the crystal phase transformed into SiO₂, which severely limits its application. Therefore, these results will provide guidance for the selection of structural materials in the future.  相似文献   

    

Panfeng Shu  Xiaomin Xie  Feng Li  Lijuan Jia  Wenjia Xu  Masahiro Oya 《International Journal of Adaptive Control and Signal Processing》2024,38(4):1222-1241

This paper introduces a novel fully actuated multirotor unmanned aerial vehicle (UAV) and develops an adaptive control scheme for it without relying on velocity signals. Conventional multirotors are limited by their strong coupling between translation and rotation motion, which makes it difficult to operate one motion without affecting the other. However, this novel multirotor's fully actuated design allows for independent translation and rotation motion, leading to better operational performance and expanded application scope. Additionally, velocity measurement signals can be prone to noise pollution and signal drift, making them unreliable for control purposes. Therefore, this proposed control scheme is developed without using velocity signals. The study utilizes a control performance improving method and guarantees stability of the closed-loop system using the direct Lyapunov method. Finally, numerical simulations are employed to demonstrate the effectiveness of the proposed control scheme.  相似文献   

    

Hideyasu Nakamura  Masami Oya  Takashi Hanamoto  Daiji Nagashio 《臭氧:科学与工程》2017,39(6):397-406

More than 20 years have passed since the introduction of advanced water treatment with ozonation and granular activated carbon in the Hanshin Water Supply Authority. Significant improvements have been achieved in eliminating taste and odor compounds in water and in suppressing the formation of disinfection by-products. Regarding the bromate ion, we have managed to suppress its formation by keeping the residual ozone concentration and pH low.  相似文献