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31.
The micellization behavior of amphiphiles is a well-analyzed physicochemical phenomenon, which can be easily influenced by various parameters such as pressure, temperature, and the presence of different additives. Inorganic salts are able to affect the thermodynamic and surface properties of amphiphiles significantly. The effect of a series of salts as additives namely lithium chloride (LiCl), potassium chloride (KCl), sodium chloride (NaCl), sodium bromide (NaBr), and sodium iodide (NaI) on interfacial chemical characteristics of the surface-active ionic liquid (SAIL) 1-dodecyl-3-methylimidazolium chloride [C12mim][Cl] in aqueous solution were examined through conductance, surface tension, fluorescence, 1H NMR, and dynamic light scattering measurements. The interfacial and thermodynamic parameters of all investigated SAIL-salt systems were evaluated from surface tension and conductance measurements, respectively. A detailed analysis of the microenvironment of the micelles and the size of the micelles was done using 1H NMR and dynamic light scattering measurements. 相似文献
32.
在半导体封装基板检测的传输过程中,末端执行器对其快速稳定高效率的传输起着关键作用。在满足设计强度、刚度的条件下,以末端执行器轻量化为目标,建立了末端执行器的三维模型,利用有限元分析软件ANSYS对基板传输机器人末端执行器进行静力学和模态分析,得到末端执行器在最大载荷情况下的应力、应变特性和对应的振型,并对其进行拓扑优化设计,根据拓扑优化结果建立新的末端执行器结构,对新的结构进行强度校核,验证设计方案的有效性。研究结果表明,优化后末端执行器的前四阶固有频率都大于伺服电动机的回转频率(50Hz),质量减少了26.7%,较好地实现了轻量化的目标,同时为后续的相关产品研制提供了一种新的技术方案。 相似文献
33.
《Ceramics International》2021,47(18):25863-25874
The inherent brittleness of bioceramics restricts their applications in load-bearing implant, although they possess good biocompatibility and bioactivity. ZnO, MgO and 58S bioglass (BG) were incorporated as additives to further improve the mechanical properties and biocompatibility of β-TCP and ZnO/MgO/BG-β-TCP composite scaffolds were manufactured via digital light processing (DLP). The composite with the best comprehensive performance was selected for degradation behavior and biocompatibility evaluation. The effects of different proportions of ZnO/MgO/BG on mechanical strength were analyzed and ZnO0·5/MgO1/BG2-β-TCP (ZMBT) samples exhibited superior mechanical strength. The improvement by 272% and 99% respectively was achieved in fracture toughness and compressive strength with the optimal recipe. The enhancement effect is realized through phase transition, alterative sliding actions and transgranular fracture to effectively prevent the load transfer combining the functions of bioglass and metal oxide. ZMBT scaffolds exhibited a more desirable pH environment and an enhanced ability of apatite-mineralization formation, meanwhile Si4+, Mg2+ and Zn2+ were gradually released from scaffolds. Furthermore, in vitro evaluation indicated that ZMBT scaffolds presented not only excellent cell attachment, proliferation, alkaline phosphatase (ALP) activity, but they up-regulated osteogenic gene (ALP, OCN, Runx2). These results suggest that the addition of ZnO/MgO/BG to DLP-printed β-TCP scaffolds offer a smart strategy to fabricate porous scaffolds with conspicuously better biological and physicochemical properties including compressive strength, bioactivity, osteogenesis and osteogenesis-related gene expression. Metal-oxide and BG synergistically enhanced the mechanical and biological properties which make the ZMBT scaffolds a strong candidate for bone repair applications. 相似文献
34.
Lucas Portela Oliveira Camila Cristina de Foggi Bruna Natália Alves da Silva Pimentel Marcelo Assis Juan Andrés Elson Longo Carlos Eduardo Vergani 《Ceramics International》2021,47(16):22604-22614
The present study reports for the first time the performance of silver phosphate (Ag3PO4) microcrystals as photocatalyst (degradation of Rodamine B-RhB) and antifungal agent (against Candida albicans–C. albicans) under visible-light irradiation (455 nm). Ag3PO4 microcrystals were synthesized by a simple co-precipitation (CP) method at room temperature. The structural and electronic properties of the as-synthetized Ag3PO4 have been investigated before and after 4 cycles of RhB degradation under visible light using X-ray diffraction (XRD), micro-Raman spectroscopy, UV–Vis spectrophotometer and field emission scanning electron microscopy (FE-SEM) images. The antifungal activity was analyzed in planktonic cells and 48h-biofilm of C. albicans by colony forming units (CFU) counting, confocal laser and FE-SE microscopies. Statistical analysis was carried out using SPSS software. Morphological and structural modifications of Ag3PO4 were observed upon recycling. After 4 recycles, the material maintained its photodegradation property; an eightfold increase in the efficiency of Ag3PO4 was observed in planktonic cells and a two fold increase in biofilm when irradiated under visible light. Thus, higher antifungal effectiveness against C. albicans was obtained when associated with visible-light irradiation. 相似文献
35.
Jin He Young Jin Jo Xianglang Sun Weiguo Qiao Jehyung Ok Tae-il Kim Zhong'an Li 《Advanced functional materials》2021,31(12):2008201
Squaraine dyes (SQs) are an important class of polymethine dyes with a unique reasonable-stabilized zwitterionic structure, in which electrons are highly delocalized over the conjugated bridge. These dyes can not only be easily synthesized via a condensation, but also exhibit intense absorption and emission in the visible and near-infrared region with excellent photochemical stability, making them attractive material candidates for many photoelectric and biomedical applications. Thus, in this review, after an introduction of SQs, the recent advances of SQs in the photovoltaic field are comprehensively summarized including dye-sensitized solar cells, organic solar cells, and perovskite solar cells. Then, the important advances in the use of SQs as the biosensors, biological imaging, and photodynamic/photothermal therapy reagents in the biomedical field are also discussed. Finally, a summary and outlook will be provided with some new perspectives for the future design of SQs. 相似文献
36.
Xue Li Xianjun Lyu Xiaohan Zhao Yan Zhang Stephen Nyabire Akanyange John C. Crittenden Huaqing Zhao Tianlin Jiang 《International Journal of Hydrogen Energy》2021,46(35):18376-18390
In this study, GO and Fe2P were used as co-catalysts to improve the separation efficiency of photogenerated electron-hole pairs in an In2S3 photocatalyst. The metallic character of Fe2P provided a cheap substitute for traditional noble metal co-catalyst for H2 production in aqueous media. The GO/Fe2P/In2S3 composite demonstrated significantly enhanced photocatalytic activity compared to pure In2S3, delivering a H2 production rate of 483.35 μmol h?1 g?1 and a quantum yield was 22.68% under visible light irradiation. The design of the photocatalyst was optimized using “Design Expert” software. The analysis showed that a GO loading of 1.18 wt%, a Fe loading of 5.36 wt%, and a calcination temperature of 180 °C were optimal. 相似文献
37.
《Advanced Powder Technology》2020,31(12):4585-4597
Focussing on visible light active ferrites for high performance removal of noxious pollutants, we report the synthesis of Mg0.5NixZn0.5-xFe2O4 (x = 0.1, 0.2, 0.3, 0.4, & 0.5) ferrite nanoparticle for degradation of reactive blue-19 (RB-19). Lattice parameters calculated using intense X-ray diffraction (XRD) peaks and Nelson-Riley plots (N-R plot) are in well agreement with each other. The sample Mg0.5Ni0.4Zn0.1Fe2O4 (M5N4) exhibits best performance with 99.5% RB-19 degradation in 90 min under visible light. Photoluminescence (PL) results confirm that recombination of charge carriers is highly reduced in the photocatalyst. Scavenging experiments suggest that O2− radicals were the dominant species responsible for photocatalytic performance. The photocatalytic mechanism was explained in terms of dopant driven shifting of conduction bands and valence bands (calculated by Mott-Schottky plots). The thermodynamic probability of radical generation along with role of redox cycles of metal ions has been discussed in the mechanism. The dye degradation was ascertained by detection of intermediates via mass spectrometry analysis and a possible degradation route was also predicted. The findings in this work provide intriguing opportunities to modify the electronic band structure of spinel ferrites for visible and solar light photocatalytic activity for environmental detoxification. 相似文献
38.
设计出基于几何相位的介质超表面实现线偏振光聚焦功能。该设计打破了传统设计中几何相位(Pancharatnam-Berry phase)的手性限制,不再是局限于左旋圆偏振光(LCP)和右旋圆偏振光(RCP)入射。通过有限时域差分仿真来证明这种线偏振聚焦相位调控的特性。该类功能器件可能用于设计新颖的THz元器件、高分辨成像、功能探测等方面。 相似文献
39.
Influence of light on the chroma of low pressure hydrogenation aviation kerosene was studied using different lights (ultraviolet light, infrared light, sunlight and no light) in the same environment full of oxygen. UV light with short wavelength has the largest influence. Coloring substances were isolated by adsorption on neutral alumina followed by ether extraction and identified by using infrared spectrum, elemental analysis and two-dimensional GC-MS. Oxygen-containing compounds are main coloring substances. Light can provide the required energy to convert unsaturated hydrocarbons and heteroatom compounds to phenols, quinones and ketones. 相似文献
40.