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101.
Wenlu Song Rui Huang Hao Guo Chunguang Yin Chuanling Wang Jun Cheng Weijuan Yang 《中国化学工程学报》2021,37(9):114-120
Steam pretreatment was employed to disrupt microalgal cells for lipids extraction.Effects of steam pre-treatment on microstructure of microalgal cells were investigated through scanning electron microscopy(SEM) and transmission electron microscopy (TEM).Effect of treatment on lipid extraction was also stud-ied.Microalgal cell walls were distorted after steam pretreatment due to the hydrolysis of organic macro-molecules contained in cell wall.Maximum curvature was increased from 1.88 × 10-6 m-1 to 1.43 × 10-7 m-1 after treatment with the steam at 130 ℃.The fractal dimension of microalgal cells increased from 1.25 to 1.30 after pretreatment for 15 min,and further increased to 1.47 when the pre-treatment time was increased to 60 min.Increased steam pretreatment temperature and time enhanced the hydrolysis of organic macromolecules,and finally destroyed microalgal cell walls at pretreatment temperature of 130 ℃ and pretreatment time of 60 min.Lipid extracted from wet microalgal was signif-icantly increased (2.1-fold) after pretreatment. 相似文献
102.
Zewen Chen Zhenhua Wang Boxiang Wang Juntang Yuan Lei Huang Zengbin Yin 《International Journal of Applied Ceramic Technology》2021,18(6):2010-2019
In this study, WC-8Co cemented carbides were prepared by spark plasma sintering. When the samples sintered at 1300℃ were cooled to room temperature, the samples were sintered multiple times at 1250℃. The changes in microstructure and mechanical properties of WC-8Co cemented carbides prepared by multiple spark plasma sintering were studied. The hardness of cemented carbides increased in the first two sintering, reaching 16.5 GPa. However, the hardness decreased seriously in the last two sintering. The attenuation rates of hardness were 6.2% and 2.5% due to the abnormal coarse grains. Furthermore, the crack path along the grain boundary was almost straight, causing a decrease in the indentation fracture toughness of cemented carbides. Additionally, the grains of cemented carbides were abnormally coarsened, and the morphologies of grains became unstable due to multiple sintering. 相似文献
103.
Yin Ruitong Zhang Shaoshuai Xu Yueyang Xue Jianming Bi Jiaqian Liu Ruijiang 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(8):3584-3594
Journal of Inorganic and Organometallic Polymers and Materials - Magnetic CoxCu(1–x)Fe2O4 nanoparticles were prepared via an alcohol solution of nitrate combustion and calcination process.... 相似文献
104.
105.
Nie Zuoren Zhang Xinming Yin Zhimin Department of Materials Science Engineering Central South University of Technology Changsha 《中国有色金属学会会刊》1997,(3)
MICROSTRUCTURESANDTEXTURESINCOLDROLLEDALUMINIUMSTRIP①NieZuoren,ZhangXinming,YinZhiminDepartmentofMaterialsScienceandEngineri... 相似文献
106.
研究了热爆合成-热挤压法制得的TiNi合金棒材的组织结构和性能。研究结果表明,所制取的棒材具有用传统法——熔铸法生产TiNi合金的性能,证明了用该法制取TiNi型材的途径是可行的 相似文献
107.
深冷处理与工模具的耐磨性 总被引:8,自引:2,他引:8
热处理后的金属材料再经低落曙处理,其力学能明显提高,尤其是高碳高合金工模具钢的耐磨性提高特别显著。本文着重研究了应用面较广的W6Mo5Cr4V2钢的处理工艺制度,组织性能及其磨损机理。 相似文献
108.
Highly conductive transparent aluminium-doped ZnO (ZnO:A1) films were successfully deposited by CW-CO2 laser-induced evaporation. Optimisation of evaporation parameters was based on laser power, substrate temperature, O2 partial pressure in the vacuum chamber and amount of Al in the ZnO source pellet. ZnO:A1 films with an electrical resistivity as low as 6.6 × 10−2Ω·cm and an optical transmission of 80% at 500nm were obtained at laser power of 15 W, substrate temperature of about 200°C, O2 partial pressure of 6—7 × 10−4 Torr and 5wt.% Al. Conductivity of ZnO films can be increased one order via Al-doping in ZnO films. The films obtained by laser-induced evaporation have compared quite favorably with the high quality films obtained by sputtering. 相似文献
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