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1.
为了解破碎围岩分别采用锚杆支护、锚喷支护以及锚喷+锚索耦合三种支护方式下的支护效果,进而为破碎围岩巷道选择合理的支护方式提供参考。通过借助FLAC3D软件建立数值模型,分析不同支护条件下的破碎围岩巷道位移量、应力分布以及塑性区的时空演化特征。结果表明,采用锚喷+锚索耦合支护时,可以较好的控制巷道围岩的位移量、减小应力集中效应、缩小塑性区的影响范围。 相似文献
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
3.
采用粉末冶金法将纳米单质铜(Cu0)、硅铁(FeSi)、四氧化三铁硅涂层(Fe3O4@SiO2)混合煅烧并制备出新型磁性硅铁载铜吸附剂MagFeSi-Cu0。实验研究不同烟气温度下MagFeSi-Cu0的汞吸附能力基础上,结合颗粒内扩散模型、准二阶动力学模型、Elovich模型及Bangham模型分析了MagFeSi-Cu0吸附Hg0过程的主要控制步骤。在此基础上,依据密度泛函理论(DFT)研究了不同反应温度下FeSi表面Cu0原子与Hg0原子的汞齐作用机制。研究结果表明,Bangham模型的拟合值与MagFeSi-Cu0汞吸附实验值拟合度最高,MagFeSi-Cu0表面痕量Hg0吸附由汞的外扩散和表面铜汞齐吸附共同控制;通过密度泛函计算,发现Cu0颗粒表面Cu-Hg齐吸附能为-0.534 eV,当烟气温度从80℃上升至200℃时,Hg0原子与单质Cu原子的吸附自由能从-22.47 kJ/mol下降至-13.96 kJ/mol,这些结果为深入了解Hg0在Cu(111)表面的反应机理提供了理论基础。 相似文献
4.
Yan He Kangren Kong Zhengxi Guo Weifeng Fang Zaiqiang Ma Haihua Pan Ruikang Tang Zhaoming Liu 《Advanced functional materials》2021,31(26):2101291
Sensitivity and multi-directional motivation are major two factors for developing optimized humidity-response materials, which are promising for sensing, energy production, etc. Organic functional groups are commonly used as the water sensitive units through hydrogen bond interactions with water molecules in actuators. The multi-coordination ability of inorganic ions implies that the inorganic ionic compounds are potentially superior water sensitive units. However, the particle forms of inorganic ionic compounds produced by classical nucleation limit the number of exposed ions to interact with water. Recent progress on the inorganic ionic oligomers has broken through the limitation of classical nucleation, and realized the molecular-scaled incorporation of inorganic ionic compounds into an organic matrix. Here, the incorporation of hydrophilic calcium carbonate ionic oligomers into hydrophobic poly(vinylidene fluoride) (PVDF) is demonstrated. The ultra-small calcium carbonate oligomers within a PVDF film endow it with an ultra-sensitive, reversible, and bidirectional response. The motivation ability is superior to other bidirectional humidity-actuators at present, which realizes self-motivation on an ice surface, converting the chemical potential energy of the humidity gradient from ice to kinetic energy. 相似文献
5.
Yuanming Wu Xiaohua Chen Li Wang Lunjie Wu Lu Lin Wenwu Ding Zhenming Che Jianfeng Wang Jianzhou Li Yi Liu Weifeng Sun 《International Journal of Food Science & Technology》2020,55(4):1825-1832
Preparation of flavour peptides with microorganisms is an attractive choice for its large-scale production. However, beefy meaty peptide (BMP), as a research hotspot in the field of umami peptide, has been studied in few microorganisms, and furthermore, the safe preparation of BMP has not yet been reported. In this study, multi-copy BMP (8BMP) was successfully expressed and produced in the ‘generally recognized as safe’ Bacillus subtilis (B. subtilis). Firstly, 8BMP with the potentially intense umami was screened out based on molecular docking analysis. Then, it was successfully expressed in the B. subtilis 168 and verified through sensory evaluation. Finally, the scaling capacity of 8BMP was evaluated in a 5-L fermenter, with the highest yield (0.84 g L−1) 6.4 times than that of shake flask, which is conductive for industrial production of BMP and other food peptides. 相似文献
6.
随着人类社会的发展,放射性铀矿的开采和使用越来越多,环境面临着越来越严重的放射性污染问题。从生物和环境的角度来看,有效地清除环境中的放射性核素是核能利用过程中最重要的问题之一。纳米零价铁(nanoscale zero valent iron, nZVI)具有较大的比表面积和较高的活性位点,能显著提高放射性污染物的修复效率。本综述的目的是展示nZVI基材料对放射性核素的高效去除能力和环境修复作用。简介了常用的nZVI基材料(表面改性或多孔材料支撑的nZVI材料)及其对放射性核素的去除效果和相互作用机制(如吸附和氧化还原)。最后,对nZVI材料的应用和挑战给出个人见解。本综述有助于为高效去除放射性核素的nZVI材料的设计指明方向,为放射性核素的高效处理处置提供新材料。 相似文献
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8.
Zhou Wenhui Wu Jie Zhong Weifeng Zhang Haochuan Shu Lei Yu Rong 《Mobile Networks and Applications》2019,24(3):950-961
Mobile Networks and Applications - Energy trading mechanism for microgrids has an inherent two-layer architecture, in which the energy trading at the first layer is between a microgrid aggregator... 相似文献
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10.
土坯砌体短柱加固选用GFRP格栅和钢丝网两种材料,对3种GFRP格栅及2种钢丝网的8种加固方式进行了轴压试验,发现GFRP格栅和钢丝网加固能够提高试件的抗压强度,格栅加固试件的抗压强度平均值提升12.33%~37.0%,钢丝网加固试件的抗压强度平均值提升29.33%~56.67%,试件的变形能力和整体性也得到了显著改善;GFRP格栅的单双层加固的效果近似,刚度大的钢丝网比刚度小的加固效果要好,GFRP格栅单层加固效果比单层钢丝网要好;所有加固方法中双层钢丝网加固效果最好. 相似文献