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71.
72.
Longyi Li Jing Yan Feng Wang Bingchao Qin Guang Chen Zhenghua Tang Hongtao Zhang Li Liao Jun Wang 《International Journal of Hydrogen Energy》2021,46(37):19508-19522
The corrosion behavior of austenitic stainless steel after low-temperature liquid oxy-nitriding (LON) was investigated by exposing in H2S/CO2-saturated liquid and vapor environments up to 720 h at 60 °C. The corrosion rates before and after LON were compared by the weightlessness method, and the microstructure as well as the corrosion scales were characterized using surface analysis methods. The results indicated that the composite S-phase layer with the outer Fe3O4 layer and the inner nitrogen-rich sublayer could improve the corrosion performance in H2S/CO2-saturated environment. The base material (BM) suffered local corrosion first, which then transformed into uniform corrosion. As a comparison, The LON sample, covered with a thin corrosion product layer, indicated slight local corrosion. The excellent corrosion resistance of the S-phase should be attributed to the blocking effect of the continuous Fe3O4 film as well as the suppression of the atomic mobility by the nitrogen-containing supersaturated solid solution. 相似文献
73.
Hongyan Liu Yuchang Qin Qing Ma Qingyu Zhao Xiaoqing Guo Lina Ma Chunlin Gou Yu Xia Ren-You Gan Junmin Zhang 《International Journal of Food Science & Technology》2021,56(6):2604-2611
In the study, lamb, feed and soil samples were collected from three regions of China in the year 2017 and 2018. The δ13C and δ15N values in lamb (defatted dry mass and lipids) and grass and the contents of nine elements in lamb, grass and soil were determined. The results indicated that except for Fe, Zn and Rb, most variables of lamb showed significant differences among two or three regions, and the contents of Fe, Sr and Cs showed significant differences between two years, and the contents of Cu and Zn showed significant differences among different muscle sections. Besides, significant correlations were found for δ13C between defatted lamb and lipid (r2 = 0.973, P < 0.05) and for the element contents between lamb and soil. Finally, four key variables δ13C, δ15N, Sr and Mo were selected through stepwise canonical discriminant analysis with the cross-validation correct classification rate of 99.1%. 相似文献
74.
Fire Technology - Thermal response of the honeycomb sandwich structure was evaluated using the steady-state method at different temperatures ranging from 100°C to 400°C. The results... 相似文献
75.
Rui Cui Jiatong Yan Jianxin Cao Yuyue Qin Minglong Yuan Lin Li 《International Journal of Food Science & Technology》2021,56(8):3670-3681
This work aimed to prepare a controlled-release antibacterial food packaging film by solvent volatilisation using chitosan (CS) and acidified modified montmorillonite (MMt) loaded with CIN (acid-MMt-CIN). MMt was successfully acidified and CIN was successfully loaded into acid-MMt, which had been confirmed by X-ray diffraction. The coordination of acid-MMt-CIN significantly increased the barrier properties of CS film to water vapour, as well as the rigidity and ductility of the film. Furthermore, the CS/acid-MMt-CIN film could significantly improve their UV resistance. It was found that the CIN release time of CS/acid-MMt-CIN film in isooctane (simulated fatty food) could reach 168 h, which was 72 h longer than that of CS/CIN film. The addition of acid-MMt-CIN had a significant inhibitory effect on Staphylococcus aureus and Escherichia coli. In short, CS/acid-MMt-CIN film could potentially be used as an antibacterial active food packaging film. 相似文献
76.
77.
Huan-yu Tao Qin Hu Yi Wu Peng Han Xiaobo Liang 《International Journal of Food Science & Technology》2021,56(8):3807-3813
A strain, Rahnella aquatilis L103, which was isolated from the soil around the roots of mushrooms, produced antibacterial protein though fermentation. This protein has broad antibacterial spectrum towards gram-positive and gram-negative bacteria. The protein has a significant antioxidant capacity on scavenging ABTS+· (82.5%, 120 μg mL−1), DPPH· (64.1%, 600 μg mL−1) and OH· (60.1%, 750 μg mL−1) as well. The protein was considered to be safe within concentration of 150 μg mL−1 as shown by MTT results and was applied to beef refrigerated preservation. The treatment group presented lower total viable counts (TVC), total volatile basic nitrogen (TVB-N), 2-thiobarbituric acid (TBA), meanwhile, higher sensory score and longer shelf life (2 days) compared with the control group (P < 0.05). The results indicated that the protein under safe concentration was beneficial to beef preservation. 相似文献
78.
79.
AbstractIn this work, the coupling phase change heat transfer process and thermal stress behavior of biological tissue during cryosurgery are studied in the context of a generalized thermoelastic theory. The nonlinear governing equations are constructed while considering the variable thermal properties and solved by a time-domain finite element method based on the effective heat capacity formulation. A 2-D tumor and normal tissue model is adopted for simulating the freezing process in cryosurgery. The effects of temperature-dependent thermal properties and relaxation time on the responses of biological tissue are discussed and illustrated graphically. 相似文献
80.
采用冷态物理模型结合商用CFD(Computational Fluid Dynamics)软件,对山东某火电厂300 MW机组配套托盘塔的流场和阻力特性进行了研究,取得了孔板阻力损失与液气比之间的二次函数关系。研究结果表明,塔内两相流场分布合理,入口处液滴受烟气的拖拽作用形成明显的干湿界面,负荷和液气比是影响脱硫塔阻力的重要因素。当液气比一定时,托盘上方能够维持相对稳定的持液层及鼓泡过程;满负荷运行时,脱硫塔阻力损失约为1600 Pa,其中孔板占1/4,持液层占3/4。拟合获得了托盘区阻力损失同液气比之间的关系,为托盘塔的应用、运行及优化提供了理论指导。 相似文献