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2.
Xuejie Li Yaqing Wen Jian Zhang Dongyun Ma Jie Zhang Yanxia An Xiaoyan Song Xiujuan Ren Weifeng Zhang 《International Journal of Food Science & Technology》2022,57(3):1544-1553
The effects of non-thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles ( FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products. 相似文献
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4.
Tian Shi Xuewu Li Chuanwei Zhang Hongxing Wang Zhenyan He Xuegang Zhou Danni Yang Hejie Yang Binbin Zhang Kang Yang 《工业材料与腐蚀》2021,72(5):904-911
Corrosion and wear failures are bottlenecks for restricting applications and developments of Al-based functional materials. As a new lubrication technology, superhydrophobic preparation provides an effective way to settle Al alloy corrosion. The preparation methods of superhydrophobic Al alloys are mainly multistep strategies. In this study, superhydrophobic Al alloy, has been prepared by an efficient one-step electrochemical etching process. Meanwhile, its micromorphology has been observed by a scanning electron microscope. The wettability has been measured by video optical contact angle meter. The corrosion behavior has been tested by electrochemical workstation, and wear performance has been characterized by friction tester. The results show that the micro-nanoterraced concave–convex structure has been fabricated and an as-prepared surface exhibits excellent superhydrophobic behavior. Further electrochemical and tribological tests show that corrosion resistance and wear resistance have also been significantly improved. This study provides a new method to prepare wear-resistant and corrosion-resistant Al alloy for widening applications of multifunctional Al-based engineering materials. 相似文献
5.
The ceramic joining using electric field (E-field) has garnered significant research attention due to the decreased joining barrier and enhanced reliability. However, the underlying mechanism of E-field assisted joining remains unclear. Herein, we report the rapid joining of alumina ceramics using a small current. Moreover, the E-field is applied in both perpendicular and parallel directions to the faying surfaces, demonstrating a significant difference in terms of joint strength. These results indicate that the E-field generates defects and promotes the joining process by facilitating ionic diffusion. 相似文献
6.
Yanqing Zhao Yingli Su Wangcai Zou Gang Chen Yiqing Deng Jun Cheng Haisheng Ren Qiang Zhao 《应用聚合物科学杂志》2021,138(38):50971
In order to prepare waterborne polyurethane with excellent water resistance and thermodynamic properties, a series of side chain fluorinated waterborne polyurethane-urea (FWPU-UA) was synthesized with polytetramethylene ether glycol, N-(2-methyl-1,3-propanediol-2′-)-perfluoro-1-butanesulfonyl amine (NPBA), isophorone diisocyanate, and isophoronediamine. With the increase of NPBA content, the weight loss temperature, glass transition temperature, and tensile strength of FWPU-UA were all improved. Gaussian fitting analysis of infrared data and density functional theory simulation proved that the introduction of fluorine side chains increased the interaction of hydrogen bonding in the FWPU-UA. X-ray photoelectron spectroscopy analysis indicated that the aggregation of fluorine atoms on the surface of film were caused by the migration and enrichment of fluorine side chains. Furthermore, the water resistance of polyurethane-urea film could be significantly improved by adding a small amount of NPBA, and the seven-day water absorption rate of polyurethane-urea film was reduced from 30.13% to 12.55%. 相似文献
7.
Fenglin Hua Hong Wei Fupeng Ren Mingming Wang Li Li Bolin Lv Huan Wang Zhiwang Yang Ziqiang Lei 《火与材料》2022,46(1):95-106
A novel ternary hybrid flame retardant named P-g-C3N4@PGS-Ti was prepared through step-by-step method. First, titanium dioxide was loaded on PGS to make PGS-Ti (where PGS = palygorskite), and then, PGS-Ti was decorated by phosphor-doped g-C3N4 (abbreviated as P-g-C3N4) to prepare a ternary flame retardant of P-g-C3N4@PGS-Ti. It showed that P-g-C3N4@PGS-Ti could efficiently improve the flame retardancy of epoxy resins (EP). The structure and the morphology of P-C3N4@PGS-Ti were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scaanning electron microscopy and hermogravimetric analysis (TGA). The flame retardancy and the burning behavior of 5 wt% P-g-C3N4@PGS-Ti composited EP were well investigated through TGA, limiting oxygen index (LOI), cone calorimeter test (CCT) and vertical burning test (UL-94 standard). It was found that the peak heat releasing (pk-HRR) of the EP/P-g-C3N4@PGS-Ti composite reduced 36% (from 1459 to 852 kW/m2) with the addition of 5 wt% of P-g-C3N4@PGS-Ti flame retardant to the matrix of EP. The combustion residue analysis showed that the EP/P-g-C3N4@PGS-Ti composite gained the most continuous and firmest char yield due to the synergistic effect of PGS, TiO2 and the introducing of P element. The mechanism proved that the combination of gas phase and condensed phase flame-retardant processes were well coordinated to improve the fire retardancy for EP. We tested and studied the mechanical properties of EP/P-g-C3N4@PGS-Ti composites. Only 2.4% decreasing of flexural strength and 23.5% decreasing of impact strength in EP/P-g-C3N4@PGS-Ti composites compared to pure EP, respectively. But according to the test results of EP/P-g-C3N4@PGS-Ti composite material and the control sample in the system, EP/P-g-C3N4@PGS-Ti composite material had the highest flexural modulus and impact strength. 相似文献
8.
Song Tian Yulei Zhang Lu Zhou Shilin Huang Junjie Ren Jincui Ren Shouyang Zhang Hejun Li 《Journal of the European Ceramic Society》2021,41(1):73-83
HfC nanowires modified carbon fiber cloth laminated carbon/carbon (HfCnw-C/C) composites were fabricated by in situ growth of HfC nanowires on carbon cloths via catalytic CVD, followed with lamination of the cloths and densification by pyrolytic carbon (PyC). Morphologies, thermal conductivity, coefficient of thermal expansion (CTE), and ablation resistance of the composites were investigated. Due to the loading of HfC nanowires, the matrix PyC with low texture was obtained; the thermal conductivity of the composites in the Z direction was enhanced from 100℃ to 2500℃; CTE along the X–Y direction also decreased in the range of 2060 ℃ – 2500 ℃, which reaches the maximum of 24 % at 2500℃. Moreover, the 20s-ablation-resistance of HfCnw-C/C composites exhibits mass and linear ablation rates of 5.3 mg/s and 21.0 μm/s, which are 40 % and 37 % lower than those of pure C/C composites, respectively. Our work shows laminated HfCnw-C/C composites are a promising candidate for high-temperature applications. 相似文献
9.
Haiyang Chen Bin Li Xue Yang Guangqi Li Hongqiang Chen Junhong Chen Bo Ren 《Ceramics International》2021,47(16):22911-22917
Understanding the spheroidization process of micron-scaled α-Al2O3 powder in hydrothermal method is of great importance but still not completely revealed. The results demonstrated that SO42? played a significant role in the formation of spherical powder, while the bubble generated from the reaction of urea didn't work in the spheroidization process. The spheroidization process was summed up as two steps. The first was that SO42? limited the hydrolysis of Al3+ and reacted with Al3+ and OH- to form Al4(OH)10SO4, which nucleated and agglomerated into granular precipitates. The second was Ostwald ripening, which gave the spherical precursors a double-layered structure. When the spherical precursors obtained 120 °C were sintered at 1200 °C, α-Al2O3 were got and the spherical morphology still maintained with a large number of nano-sized pores. We anticipate the spherical α-Al2O3 with nano-sized pores can be applied in adsorption and filtration industries. 相似文献
10.
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