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71.
Yu Cao Jiayu Li Jun Liu Hongbo Liu Yan Jiang Hongwen Zhang 《Polymer International》2019,68(4):694-699
A novel ion‐imprinted polymer (IIP) using (6‐O‐butene diacid ester)‐β‐cyclodextrin (β‐CD‐MAH) as the functional monomer and copper ions as the template was developed for Cu2+ sensing. First, reactive β‐cyclodextrin (β‐CD) monomers with vinyl carboxylic acid functional groups were synthesised and were co‐polymerised with styrene via radical polymerisation. Then, the β‐CD copolymers were complexed with Cu2+ in order to obtain the IIP. The imprinting effect was realised by removing the template ions from the imprinted polymer. The structure, composition and morphology of the IIP were characterised by Fourier transform IR spectroscopy, energy‐dispersive spectroscopy and field‐emission SEM. The adsorption capacity was investigated by UV–visible spectroscopy in batch operation mode. The maximum adsorption capacity for the Cu2+ template ions was 28.91 mg g?1, and the adsorption selectivity was clearly illustrated from the increased sorption affinity towards Cu2+ ions over other competing ions. The adsorption was affected by the pH of the aqueous medium, and enhanced adsorption capacity was observed at pH 5. The prepared IIP could be used 10 times after its regeneration without significant loss of the adsorption capacity. © 2018 Society of Chemical Industry 相似文献
73.
《International Journal of Hydrogen Energy》2022,47(44):19175-19194
A new method is developed in the paper to estimate the maximum available capacity which is an important basis for indicating the State of Health (SOH) of lithium-ion batteries. Firstly, a data reconstruction approach is proposed to pre-process the acquired data to suppress the influence of measurement noise and reduce the negative impact on estimation precision when measuring equipment adopts different sampling frequencies. Then, the variation trend of the incremental capacity curve obtained based on the reconstructed data with the battery aging is analyzed, and a health indicator (HI) including multi-view features is put forward to characterize the battery degradation more comprehensively. The multi-view features are coming from the capacity increment curve versus voltage and time, including the maximum value of the capacity increment curve, the voltage corresponding to the maximum value, other values surrounding the maximum value and so on. Finally, Support Vector Regression is used to establish a model between the extracted HI and the maximum available capacity, and two types of open source data are used to verify the performance. The experimental results show that the data reconstruction method and multi-view health indicator proposed in the paper can obtain high precision estimation results. 相似文献
74.
《Calphad》2020
The sodium pyrovanadate (Na4V2O7) powder was synthesized by solid-state reaction using sodium carbonate (Na2CO3) and vanadium pentoxide (V2O5) as raw materials. X-ray powder diffraction (XRD), scanning electron microscope (SEM), and differential scanning calorimeter (DSC) were used to accurately characterize the synthesized sample. The solid-state phase transformation from α-Na4V2O7 to β-Na4V2O7 occurs at the temperature 696 K and the enthalpy is equals to 1.03 ± 0.01 kJ/mol, the endothermic effect at 931 K and the enthalpy is equals to 31.35 ± 0.31 kJ/mol, which is related to the melting of Na4V2O7. The high-temperature heat capacity of Na4V2O7 was measured using a Multi-high temperature calorimeter 96 line and DSC. The obtained high-temperature heat capacity of Na4V2O7, as a function of temperature, was modeled as: Cp=314.62+0.05T-5494390T-2 J·mol-1·K-1 (298.15-873 K). The temperature dependence on heat capacity was then used for computing changes in the enthalpy, entropy, and Gibbs free energy at the specific temperature internal. 相似文献
75.
Marely G. Figueroa-Pérez Iza F. Pérez-Ramírez Octavio Paredes-López Candelario Mondragón-Jacobo 《International Journal of Food Properties》2018,21(1):1728-1742
This study aimed to determine the phytochemical profile and nutraceutical properties of nopal cladodes (Opuntia ficus-indica) at different stages of maturity. Medium-age cladodes showed the highest total saponins, phytosterols, and indigestible fiber, as well as the highest in vitro antioxidant capacity and digestive enzymes inhibitory activity. Furthermore, these cladodes presented the highest content of p-hydroxybenzoic acid, p-coumaric acid, rutin, narcissin, nicotiflorin, β-sitosterol, and sitosteryl-3-β-glucopyranoside, as well as several amino acids, organic acids, and fatty acids. Whereas young cladodes contained the highest concentration of condensed and hydrolyzable tannins. These results demonstrated that maturity affects the nutritional and nutraceutical properties of nopal cladodes. 相似文献
76.
Patricia Garrido-Pascual Ana Alonso-Varona Begoa Castro María Burn Teodoro Palomares 《International journal of molecular sciences》2020,21(24)
Oxidative stress associated with neuroinflammation is a key process involved in the pathophysiology of neurodegenerative diseases, and therefore, has been proposed as a crucial target for new therapies. Recently, the therapeutic potential of human adipose-derived stem cells (hASCs) has been investigated as a novel strategy for neuroprotection. These cells can be preconditioned by exposing them to mild stress in order to improve their response to oxidative stress. In this study, we evaluate the therapeutic potential of hASCs preconditioned with low doses of H2O2 (called HC016 cells) to overcome the deleterious effect of oxidative stress in an in vitro model of oligodendrocyte-like cells (HOGd), through two strategies: i, the culture of oxidized HOGd with HC016 cell-conditioned medium (CM), and ii, the indirect co-culture of oxidized HOGd with HC016 cells, which had or had not been exposed to oxidative stress. The results demonstrated that both strategies had reparative effects, oxidized HC016 cell co-culture being the one associated with the greatest recovery of the damaged HOGd, increasing their viability, reducing their intracellular reactive oxygen species levels and promoting their antioxidant capacity. Taken together, these findings support the view that HC016 cells, given their reparative capacity, might be considered an important breakthrough in cell-based therapies. 相似文献
77.
在固体材料表面黏附成膜是微藻细胞的一种生理特性。近些年基于微藻生物膜的生物过程,如生物膜贴壁培养和防附着技术受到了很多关注。微藻在固体材料表面的黏附受藻细胞与材料表面之间的相互作用的影响,建立黏附强度与材料表面性质参数间的关系对于通过材料选择来强化或控制微藻生物膜具有非常重要的意义。本工作的目的是揭示和明确材料亲疏水性对微藻黏附的影响,提出了一种双酚A环氧(EP)树脂表面亲疏水改性的方法。通过将亲水性的二乙醇胺(DEA)或疏水性的聚甲基聚硅氧烷(PMHS)加入到EP树脂中反应,EP树脂表面水接触角在36.80?~98.34?范围内可通过加入不同量的DEA或PMHS实现任意可调,材料的表面水接触角与DEA或PMHS加入量之间有线性关系。重要的是这种改性方法获得的材料,其形貌、结构、表面粗糙度等表面性质几乎没有变化,从而在研究和关联微藻黏附量与材料表面亲疏水性(表面水接触角)之间的关系时可以排除亲疏水性之外的其他表面性质的影响;其次,考察了小球藻和栅藻在不同亲疏水性材料表面的黏附行为,结果表明小球藻和栅藻在亲水性和疏水性材料表面均能黏附成膜,但在亲水性材料表面黏附更多更快;建立了微藻最大黏附容量与材料表面接触角之间关联关系,表明微藻最大黏附容量随材料表面水接触角的增大而线性降低,栅藻的表面黏附容量比小球藻大。 相似文献
78.
Yang-huan ZHANG Ya-qin LI Hong-wei SHANG Zhong-hui HOU Yan QI Dong-liang ZHAO 《中国有色金属学会会刊》2018,28(4):711-721
The La-Mg-Ni-Co-Al-based AB2-type La0.8–xCe0.2YxMgNi3.4Co0.4Al0.1 (x=0, 0.05, 0.1, 0.15, 0.2) alloys were prepared via melt spinning. The analyses of the X-ray diffraction (XRD) and scanning electron microscopy (SEM) proved that the experimental alloys contain the main phase LaMgNi4 and the second phase LaNi5. Increasing Y content and spinning rate lead to grain refinement and obvious change of the phase abundance without changing phase composition. Y substitution for La and melt spinning make the life-span of the alloys improved remarkably, which is attributed to the improvement of anti-oxidation, anti-pulverization and anti-corrosion abilities. In addition, the discharge capacity visibly decreases with increasing the Y content, while it firstly increases and then decreases with increasing spinning rate. The electrochemical kinetics increases to the optimum performance and then reduces with increasing spinning rate. Moreover, all the alloys achieve to the highest discharge capacities just at the initial cycle without activation. 相似文献
79.
Bo Wang Edison Huixiang Ang Yang Yang Yufei Zhang Hongbo Geng Minghui Ye Cheng Chao Li 《Advanced functional materials》2020,30(28)
Orthorhombic molybdenum trioxide (MoO3) is one of the most promising anode materials for sodium‐ion batteries because of its rich chemistry associated with multiple valence states and intriguing layered structure. However, MoO3 still suffers from the low rate capability and poor cycle induced by pulverization during de/sodiation. An ingenious two‐step synthesis strategy to fine tune the layer structure of MoO3 targeting stable and fast sodium ionic diffusion channels is reported here. By integrating partially reduction and organic molecule intercalation methodologies, the interlayer spacing of MoO3 is remarkably enlarged to 10.40 Å and the layer structural integration are reinforced by dimercapto groups of bismuththiol molecules. Comprehensive characterizations and density functional theory calculations prove that the intercalated bismuththiol (DMcT) molecules substantially enhanced electronic conductivity and effectively shield the electrostatic interaction between Na+ and the MoO3 host by conjugated double bond, resulting in improved Na+ insertion/extraction kinetics. Benefiting from these features, the newly devised layered MoO3 electrode achieves excellent long‐term cycling stability and outstanding rate performance. These achievements are of vital significance for the preparation of sodium‐ion battery anode materials with high‐rate capability and long cycling life using intercalation chemistry. 相似文献
80.
韩玲 《食品安全质量检测学报》2020,11(21):7771-7776
肌酸(creatine)是脊椎动物体内自然存在的一种含氮类有机酸。补充肌酸能够通过调节体内磷酸肌酸水解、糖代谢和蛋白表达等方式来增加糖原的储存、提高ATP的生成、增强肌细胞的酸碱缓冲能力以及刺激肌细胞增殖,从而能够预防运动损伤、改善运动表现、提升训练适应性和加快运动后康复。自从1992年巴塞罗那奥运会上,英国短跑运动员克利斯提通过服用肌酸提高运动能力,并夺得百米冠军后,欧美运动员开始广泛的在运动和训练时服用肌酸,到1996年亚特兰大奥运会,已有60%以上的短跑运动员服用肌酸。对于从事剧烈运动训练的高水平运动员而言,需要每天摄入5-10 g肌酸以维持最佳的全身肌酸储备量,从而保持最佳的运动和训练效果。本文详细综述了肌酸的作用机制、补充肌酸对运动能力的影响、补充肌酸的安全性以及肌酸类运动营养品的使用人群、产品种类、补充策略和相关标准法规等。 相似文献