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991.
Li-Xiang Wu Lin-Lin Zhu Wei-Ming Guo Shi-Kuan Sun Wen-Bin Niu Jia-Xiang Xue Jian-Han Zhai Hai-Bin Ma Rui-Lin Lin Hua-Tay Lin Kevin Plucknett Ye-Hong Liao Tong Liu Qi-Sen Ren 《Journal of the European Ceramic Society》2021,41(1):225-232
The joining of liquid-phase sintered SiC (LPS-SiC) ceramics was conducted using spark plasma sintering (SPS), through solid state diffusion bonding, with Ti-metal foil as a joining interlayer. Samples were joined at 1400 °C, under applied pressures of either 10 or 30 MPa, and with different atmospheres (argon, Ar, vs. vacuum). It was demonstrated that the shear strength of the joints increased with an increase in the applied joining pressure. The joining atmosphere also affected on both the microstructure and shear strength of the SiC joints. The composition and microstructure of the interlayer were examined to understand the mechanism. As a result, a SiC-SiC joining with a good mechanical performance could be achieved under an Ar environment, which in turn could provide a cost-effective approach and greatly widen the applications of SiC ceramic components with complex shape. 相似文献
992.
Kongbo Sun Zhenwen Yang Ruijie Mu Shiyu Niu Ying Wang Dongpo Wang 《Journal of the European Ceramic Society》2021,41(6):3196-3206
A bulk (Hf0.2Ta0.2Zr0.2Nb0.2Ti0.2)C high-entropy ceramic (HEC) with a high density was prepared by hot pressing (HP), and through a robust joining technique, large-sized piece was fabricated. A hot-pressed carbide HEC with a single-phase and homogeneous composition was obtained at the sintering temperatures from 1800 to 1950 °C for 30 min under a pressure of 30 MPa. The influence of sintering temperature on the mechanical properties of the HEC was investigated, and the flexural and compressive strengths were reported. Additionally, the feasibility of active brazing of this HEC was studied and solid joints with high shear strength were obtained by atomic diffusion and chemical reaction at the interface, providing a key approach to fabricate complex components of HECs. 相似文献
993.
Yu Liu Xing Zou Xiaowei Niu Zhengquan Hu 《International Journal of Circuit Theory and Applications》2020,48(12):2056-2064
According to the characteristics of the chaotic oscillator in detecting weak signals, an algorithm based on Duffing chaotic oscillator array was proposed for acquisition of weak GLONASS signals. By means of GLONASS intermediate frequency and Duffing chaotic oscillator models, Lyapunov exponent is adopted to judge the critical condition of phase track and decide whether GLONASS signals exist or not by the change of the critical condition, and numeric iteration procedure is used to calculate the exponent. Finally, the performance of algorithm is simulated using GLONASS intermediate frequency data. The results indicate that acquisition algorithm can satisfy the need of object positioning in low signal-to-noise ratio environment. 相似文献
994.
Jiawei Wu Bo Niu Fan Zhang Liwen Lei Jinyong Zhang Lin Ren Weimin Wang Zhengyi Fu 《Ceramics International》2018,44(13):15323-15330
A novel method, namely flash spark plasma sintering (FSPS), combining flash sintering and electric field assisted sintering, was utilized to densify boron carbide/titanium diboride (B4C/TiB2) composites. Further, sintering homogeneity of the composites with different contents of TiB2 was systematically investigated and theoretical model was built. Results indicated that addition of 50?wt% TiB2 led to the densification of B4C/TiB2 composite by up to 97.7% with regional range 1.9% at 1872?°C under pressure of 4?MPa in 60?s. The preferential pathway of TiB2 network proves to disperse the central current and distribute thermal flow throughout the specimen possibly via tunneling, electronic field emission effect at first stage and lower-resistance composite pathway latter, contributing to the increased homogeneity. 相似文献
995.
Wenxiao Zhang Ying Feng Yifan Niu Ting Liu Xiaoyu Zhai Jiaxiang Liu 《Ceramics International》2021,47(17):23834-23843
SiC is a promising functional ceramic material with many great properties. High concentrated SiC slurry with excellent rheology and stability is required in some processes of ceramic forming. In this work, the dispersion of SiC powders was obviously improved by ternary modifiers: γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560), sodium humate and sodium dodecyl sulfate (SDS). Modified SiC slurry showed the lowest viscosity of 0.168 Pa s at a solid content of 50 vol%. The maximum absolute value of zeta potential of SiC increased from 47.3 to 61.6 mV by modification. Sedimentation experiments showed that a highly stable suspension of modified SiC was obtained at pH 10. SiC green body with high density of 2.643 g/cm3 was prepared with modified powders by slip casting. X-ray photoelectron spectra (XPS) and thermogravimetry (TG) measurements indicated the adsorption of modifiers on SiC surface. Therefore, modified SiC powders could stably disperse in aqueous media due to the increase of electrosteric repulsion between particles. The novel strategy used in this study could further improve the dispersion of SiC powders. 相似文献
996.
Sha Liu JianHui Xiao YaPing Feng MianLing Zhang Ying Li Jin Tu LiYa Niu 《International Journal of Food Science & Technology》2022,57(3):1791-1803
Konjac glucomannan/sodium alginate composite edible boba (KGM/SA-boba) with good taste is very popular in China, and it is an outstanding carrier for health potential ingredients. In this work, KGM/SA-boba were fortified with 0.25, 0.50, 0.75 and 1.00% purple sweet potato anthocyanin (PSPA), then characterised by the water distribution, texture, microstructure, in vitro release property of PSPA and antioxidant capacity. LF-NMR analysis demonstrated that the free water of KGM/SA-boba could transfer to tightly bound water with the addition of PSPA that made it with better water-binding ability, higher springiness and lower hardness. And the results of SEM and rheology showed that PSPA could stabilise the microstructure of KGM/SA-boba by forming more amorphous regions and hydrogen bonds proved by the results of DSC and FT-IR. Furthermore, 50% of PSPA in PSPA-fortified KGM/SA-boba can be released at the first hour in a simulated gastrointestinal environment. And the scavenging capacity of DPPH and ABTS of the PSPA-fortified KGM/SA-boba after digestion was higher than that of PSPA alone. Generally, PSPA could improve the texture while KGM/SA-boba in turn would make PSPA more stable in the gastrointestinal digestive system. 相似文献
997.
Weijie Zhao Jing Zhang Jiaqi Pan Wenhui Zhao Jiantao Niu Jianfeng Qiu Chaorong Li 《Ceramics International》2018,44(15):18337-18343
The 1D Ag3PO4 sensitized SrTiO3 nanowires are prepared by simple route of electrospinning-in situ deposition technique. The results of the thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive Spectrometer (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Visible diffuse reflectance spectroscopy (UV–Vis) indicate that the Ag3PO4 nanoparticles has been deposited on the surface of the SrTiO3 nanowires successfully. Experimental results showed that compared with pure SrTiO3, the as-prepared 1D Ag3PO4 sensitized SrTiO3 nanowires exhibit obvious enhancement of photocatalytic performance and stability. Especially, the Ag3PO4/SrTiO3 (3AS sample) had a satisfactory photocatalytic activity for degrading methylene blue (MB) more than 98% under visible light irradiation. As to pure SrTiO3 and Ag3PO4, only 9.8% and 49% of MB was decomposed after 35?min irradiation respectively. Furthermore, the mechanism of the enhancing photocatalytic activity could be ascribed to the nano-heterojunction of the Ag3PO4/SrTiO3, the visible light response of the Ag3PO4, and the 1D structure of the nanowires. 相似文献
998.
999.
1000.
Li Shiyu Ye Dengpan Jiang Shunzhi Liu Changrui Niu Xiaoguang Luo Xiangyang 《Multimedia Tools and Applications》2020,79(7-8):4315-4331
Multimedia Tools and Applications - Nowadays, convolutional neural network (CNN) based steganalysis methods achieved great performance. While those methods are also facing security problems. In... 相似文献