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61.
长轴表面激光淬火变形与控制 总被引:1,自引:0,他引:1
应用激光淬火强化技术控制长轴的淬火变形,分析了激光淬火变形的原因和影响因素。研究结果表明,激光淬火不仅可使长轴振摆变形量控制在很小的范围内,而且可将已变形的长轴校直到很高的精度。 相似文献
62.
Junpeng Xiong Weili Shao Ling Wang Chen Cui Yurui Jin Hongqin Yu Pengju Han Yanfei Gao Fan Liu Qingqing Ni Jianxin He 《大分子材料与工程》2021,306(11):2100371
Recently, because of the outbreak of COVID-19, the demand for various types of filter elements in protective materials has increased globally. Furthermore, new requirements for the filtration performance of PM2.5 liquid (oil) particles have been put forward. In this work, Superhydrophobic and superoleophobic composite nanofibers with excellent filtration capacity for oil and salt particles are developed through the modification of polyacrylonitrile (PAN) by fluoro-polyurethane (FPU) doping. The results show that the PAN/FPU composite nanofibers doped with 9 wt% FPU has a uniform fiber morphology with a diameter of 240 ± 30 nm. Compared to the pure PAN nanofibers, the water-based contact angle of PAN/FPU increases from 90 ± 5° to 151 ± 5°, and the oil-based contact angle increases from 58 ± 2° to 152 ± 3°. Importantly, at a high flow rate of 95 L min−1, the filtration efficiency of the PAN/FPU nanofiber membrane for 0.3 µm oil particles increases from 92 ± 1% to 99.2 ± 0.1%. After cyclic loading, the filtration efficiency of 0.3 µm oil particles remains above 98%. Meanwhile, the filtration efficiency for 0.3 µm salt particles remains at 98.23 ± 0.1%. The PAN/FPU nanofiber membrane developed in this work is effective in applications and has good market prospects as a protective filtration material. 相似文献
63.
Dr. Xicheng Liu Mingxiao Shao Congcong Liang Jinghang Guo Guangxuan Wang Xiang-Ai Yuan Zhihong Jing Laijin Tian Prof. Dr. Zhe Liu 《Chembiochem : a European journal of chemical biology》2021,22(3):557-564
A series of half-sandwich structural iridium(III) phenanthroline (Phen) complexes with halide ions (Cl−, Br−, I−) and pyridine leaving groups ([(η5-CpX)Ir(Phen)Z](PF6)n, Cpx: electron-rich cyclopentadienyl group, Z: leaving group) have been prepared. Target complexes, especially the Cpxbiph (biphenyl-substituted cyclopentadienyl)-based one, showed favourable anticancer activity against human lung cancer (A549) cells; the best one ( Ir8 ) was almost five times that of cisplatin under the same conditions. Compared with complexes involving halide ion leaving groups, the pyridine-based one did not display hydrolysis but effectively caused lysosomal damage, leading to accumulation in the cytosol, inducing an increase in the level of intracellular reactive oxygen species and apoptosis; this indicated an anticancer mechanism of oxidation. Additionally, these complexes could bind to serum albumin through a static quenching mechanism. The data highlight the potential value of half-sandwich iridium(III) phenanthroline complexes as anticancer drugs. 相似文献
64.
采用水热法制备GRQD-NiCo2O4复合物,利用XRD、SEM及TEM分析其微结构,并探讨其作为DMFC阳极催化剂使用时的电化学性能。微结构分析表明所得GRQD-NiCo2O4复合物皆为具NiCo2O4单一相的尖晶石结构,且GRQD质量浓度高于0.25 g/mL后表面形貌将转变GRQD与NiCo2O4相互结合的状态。电化学分析表明添加GRQD可有效增强NiCo2O4的导电性并提升其电化学稳定性,其中GRQD质量浓度为0.25 g/mL时所得样品经500次循环测试后电流密度约为77.5 A/g,与循环5次后相比其电流密度剩余量最大(约为69.7%),该样品作为DMFC阳极催化剂使用时性价比最佳。 相似文献
65.
简要介绍了自主设计制造、具有完全自主知识产权的1 250 mm五机架六辊冷连轧产线工艺及设备特点。重点阐述了冷连轧工艺控制系统的硬件配置、软件架构及核心技术。采用基于简易有限元的轧制力模型及基于成本函数的多目标负荷分配模型,实现了高精度的轧制规程计算。开发了原料板快速启车技术与板形多变量综合最优控制技术,实现了冷轧产品的尺寸精准控制。现场实际应用效果表明,机组稳定运行率达到99.8%以上,不同规格的产品厚度控制精度均达到±0.8%以内,板形控制精度均达到5I以内。 相似文献
66.
67.
四异丁氧基镍酞菁的合成及其溶剂效应 总被引:2,自引:0,他引:2
4 异丁氧基邻苯二腈与氯化镍在强有机碱 1 ,8 二氮杂双环 (5 ,4,0 )十一碳烯 7催化下反应 ,合成了四异丁氧基镍酞菁 ,产物经FT -IR、元素分析、UV -Vis吸收光谱和1 H NMR表征了结构 ;并研究了其溶剂效应 ,结果表明 :最大吸收峰波数ν与函数 f(n ,ε)存在一定的线性关系 ,线性相关系数为 0 940 2 ,而Bayliss函数项 (n2 - 1 ) /(2n2 +1 )决定了最大吸收波长 (λmax)的位移变化 ;化合物的λmax在不同溶剂中随聚集程度增加 ,发生一定程度的蓝移 相似文献
68.
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70.
Lingzhi Wang Yaofeng Shao Jinlong Zhang Masakazu Anpo 《Microporous and mesoporous materials》2007,100(1-3):241-249
The hydrothermal stability of MCM-48 was conveniently and effectively improved by increasing the crystallization temperature and directly adding NaF to the synthesis gel. The crystallization temperature varied from 373 K to 403 K. The influences of NaF addition, crystallization temperature and crystallization time on the formation process and hydrothermal stability of MCM-48 were systematically studied here to solve the problem of poor reproducibility. Results from XRD patterns indicated that the crystallization temperature and crystallization time were very critical factors for the improvement of the hydrothermal stability besides NaF addition. The formation process of MCM-48 was significantly accelerated and the pore structure ordering was also greatly improved by increasing the crystallization temperature and F−/Si ratio. A high hydrothermally stable MCM-48 mesoporous molecular sieve was obtained after being crystallized at 393 K for 36 h in the presence of NaF, which endured the hydrothermal treatment in boiling water at least for 4 days. However, only an amorphous product was obtained when the crystallization temperature was further increased to 403 K. Results from Si MAS NMR, N2 adsorption isotherms, TEM, Raman spectra and XRD patterns manifested that the improved stability of MCM-48 was attributed to the high silicates condensation degree and the excellent pore structure ordering. The possible reason for the successful formation of hydrothermally stable MCM-48 sample by controlling the crystallization temperature, time and F−/Si ratio was explained here. 相似文献