Comparative studies on thermal and toughness properties of polybenzoxazine composites with two functionalized graphene oxides

Abstract

Graphene oxide (GO) was functionalized by polyether amine (PEA) via two methods which were one-pot modification in acetone (GON) and two steps with the intermediate product of GOCO-Cl generated (GONS). There were more PEA successfully grafted onto GO for GONS than GON. The onset polymerization temperatures of the benzoxazine (Bz) composites decreased by the inclusion of 1?wt% of GO, GON or GONS. Thermal stability of the polybenzoxazine (PBz) composites was significantly improved indicated from the increase of weight loss temperature. T₁₀, T₂₀ and T₅₀ values of the composites with GONS were higher than that of the others. Toughness of PBzs may be enhanced by the incorporation of nanofillers, and GONS had stronger interfacial interaction with PBz matrix than GON.     

The origin of the modulated structure in Sr2CuO3+δ (δ = 0.4): [CuO2] in-plane oxygen vacancy or apical oxygen vacancy?

We propose the question of the modulated structures of copper oxide is caused by the [CuO₂] in-plane oxygen vacancy or apical oxygen vacancy. Sr₂CuO_3+δ single-crystal samples were prepared using high-temperature and high-pressure methods. The major phase of Sr₂CuO_3+δ (δ = 0.4) single-crystal system is found to be constituted by the 5 a modulated structure with the Fmmm space group, which originates from the [CuO₂] in-plane oxygen vacancy appearing in octahedral Cu-O. Besides, the presence of the [CuO₂] in-plane oxygen vacancy may obliterate the superconductivity of the system. Experimental results deduce that the oxygen vacancy may appear in the apical oxygen sites in high-temperature copper oxide superconductors.     

A dynamic SVR–ARMA model with improved fruit fly algorithm for the nonlinear fiber stretching process

Natural Computing - The fiber stretching process plays the key role in the process of fiber production and its effects is measured by the stretching ratio. The stretching ratio is determined by the...     

High-efficiency Silicon Solar Cells: A Review

Over the past few decades, crystalline silicon solar cells have been extensively studied due to their high efficiency, high reliability, and low cost. In addition, these types of cells lead the industry and account for more than half of the market. For the foreseeable future, Si will still be a critical material for photovoltaic devices in the solar cell industry. In this paper, we discuss key issues, cell concepts, and the status of recent high-efficiency crystalline silicon solar cells.     

Visualizing for the Non‐Visual: Enabling the Visually Impaired to Use Visualization

The majority of visualizations on the web are still stored as raster images, making them inaccessible to visually impaired users. We propose a deep‐neural‐network‐based approach that automatically recognizes key elements in a visualization, including a visualization type, graphical elements, labels, legends, and most importantly, the original data conveyed in the visualization. We leverage such extracted information to provide visually impaired people with the reading of the extracted information. Based on interviews with visually impaired users, we built a Google Chrome extension designed to work with screen reader software to automatically decode charts on a webpage using our pipeline. We compared the performance of the back‐end algorithm with existing methods and evaluated the utility using qualitative feedback from visually impaired users.     

北京冬奥会推动国内制冷行业可持续发展

二氧化碳制冷技术和提升氨制冷安全体系是绿色制冷的重要支撑,北京冬奥会大量采用绿色制冷技术,不仅推动国内制冷行业可持续发展,而且将对2030年碳达峰和2060年碳中和产生深远影响.     

Combination of vegetable soup and glucan demonstrates synergistic effects on macrophage-mediated immune responses

Vegetable soup (VS), a plant-based functional food, has been used as a traditional folk medicine and is attracting attention for its ability to enhance the immune response. β-Glucan, a well-established and effective immunomodulator, has synergistic effects when used in combination with some bioactive compounds. In the present study, we aimed to evaluate the synergistic immunomodulatory effects of the combination of VS and β-glucan on macrophage-mediated immune responses. β-Glucan was demonstrated to synergistically enhance the VS-stimulated immune response, including the production of interleukin-6, tumor necrosis factor-α, and nitric oxide, mainly through the mitogen-activated protein kinase pathway in macrophages. In addition, this combination has the potential for further development in functional foods with immune-enhancing activity.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10068-021-00888-x.     

有关工程建设管理现状的一些思考

为了促进我国工程建设管理由粗放式向科学化、规范化管理的转变,国家针对影响工程建设管理的几个关键环节,提出了“四制”:为了明确管理主体责任,实行了项目法人负责制;为了引进市场竞争机制,实行了招标投标制;为了实现工程质量全面专业化管理,实行了建设监理制;为了规范工程建