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991.
Lukáš Zdražil Zdeněk Baďura Michal Langer Sergii Kalytchuk David Panáček Magdalena Scheibe Štěpán Kment Hana Kmentová Muhammed Arshad Thottappali Elmira Mohammadi Miroslav Medveď Aristides Bakandritsos Giorgio Zoppellaro Radek Zbořil Michal Otyepka 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(32):2370251
Photoactivation of aspartic acid-based carbon dots (Asp-CDs) induces the generation of spin-separated species, including electron/hole (e−/h+) polarons and spin-coupled triplet states, as uniquely confirmed by the light-induced electron paramagnetic resonance spectroscopy. The relative population of the e−/h+ pairs and triplet species depends on the solvent polarity, featuring a substantial stabilization of the triplet state in a non-polar environment (benzene). The electronic properties of the photoexcited Asp-CDs emerge from their spatial organization being interpreted as multi-layer assemblies containing a hydrophobic carbonaceous core and a hydrophilic oxygen and nitrogen functionalized surface. The system properties are dissected theoretically by density functional theory in combination with molecular dynamics simulations on quasi-spherical assemblies of size-variant flakelike model systems, revealing the importance of size dependence and interlayer effects. The formation of the spin-separated states in Asp-CDs enables the photoproduction of hydrogen peroxide (H2O2) from water and water/2-propanol mixture via a water oxidation reaction. 相似文献
992.
993.
以金山片区一厂一策为例,提出现状梳理、问题分析、解决方案、列出清单、组织实施的提质增效工作思路.金山片区针对收水不全、进厂浓度低等问题开展现场调查、深入分析,提出污水处理厂扩容、完善干管系统、管网补短板、管网修复改造、管网混接改造、源头雨污分流、排水管理等技术对策. 相似文献
994.
Li Zhixin Sun Yaru Zhu Jianwei Tang Suqin Zhang Canlong Ma Huifang 《Neural computing & applications》2021,33(6):1773-1784
Neural Computing and Applications - To better learn the dependency relationship between nodes, we address the relationship extraction task by capturing rich contextual dependencies based on the... 相似文献
995.
Artificial Intelligence Review - Heuristic algorithms can give optimal solutions for low, middle, and large scale optimization problems in an acceptable time. The social spider algorithm (SSA) is... 相似文献
996.
Chen Fei Gao Yunjian Zhao Siyuan Deng Jianhui Li Zongliang Ba Renji Yu Zhiqiu Yang Zhongkang Wang Sai 《Bulletin of Engineering Geology and the Environment》2021,80(4):3475-3493
Bulletin of Engineering Geology and the Environment - On Oct. 10 and Nov. 3, 2018, two landslides, i.e., the “10.10” and “11.3” rockslides, occurred successively at Baige... 相似文献
997.
Khai Chen Tan Zijun Jing Yang Yu Yong Shen Chua Qijun Pei Dewen Zheng Xi Zhang Zhixin Ge Fudong Zhang Teng He 《International Journal of Hydrogen Energy》2021,46(19):11051-11058
Metalorganic hydrides are a new class of hydrogen storage materials. Replacing the H of N–H or O–H functional groups using metal hydrides have been recently reported, which substantially improved the dehydrogenation properties of heteroaromatic organic hydrides by lowering their enthalpies of dehydrogenation (ΔHd), enabling dehydrogenation at much lower temperatures. Among the reported metalorganic hydrides, lithium carbazolide and sodium carbazolide appear to be the most attractive hydrogen storage/delivery material owing to its high hydrogen capacity (>6.0 wt%) and ideal ΔHd. Nevertheless, the interaction of carbazole and corresponding metal hydride to form metallo-carbazolide is a multistep process involving intensive ball milling and high temperature treatment, where the interaction was not investigated in detail. In this paper, both alkali metal hydrides and amides were employed to react with carbazole to synthesize corresponding carbazolides, aiming to broaden and optimize the synthetic method and understand the reaction mechanism. Our experimental results showed that around one equivalent of H2 or NH3 could be released from the reactions of carbazole and corresponding hydrides or amides, respectively. Instrumental spectroscopic analyses proved that metallo-carbazolides were successfully synthesized from all precursors. It is found that the alkali metal amides (i.e., LiNH2 and NaNH2) with stronger Lewis basicities as metal precursors could synthesize the metallo-carbazolides under milder conditions. Furthermore, quasi in situ nuclear magnetic resonance results revealed that alkali metal could replace H (H–N) gradually, donating more electrons to carbazole ring. Additionally, the solubilized alkali cation may unselectively interact with π-electron of aromatic systems of both carbazole molecules and carbazolide anions via electrostatic cation-π interactions. 相似文献
998.
Jun Liu Huaqing Ma Shuiying Zheng Zhixin Zhang Jinyang Zheng Yongzhi Zhao 《International Journal of Hydrogen Energy》2021,46(39):20607-20620
Gaseous hydrogen stored in high-pressure cylinder is a proper solution for the application of hydrogen fuel cell buses (HFCB). As far as the on-bus hydrogen storage system (OBHSS) is concerned, the filling of hydrogen gas needs to be finished in an acceptable time, which unavoidably brings the increase of temperature of hydrogen gas in OBHSS. And excessive temperature of hydrogen gas is unfavorable to mechanical properties of wrapping material and even the service life of the storage cylinder, so it is urgent to work out effective strategies on the temperature-rise in the storage cylinder. It is noticed that the studies on the relationship between the temperature-rise and the geometrical parameters of on-bus gaseous hydrogen storage cylinder (OBGHSC), e.g. thickness of liner and fiber/epoxy composite laminate, are still not deep enough. Motivated by this fact, this research is therefore devoted to studying the relationship between the temperature-rises of both hydrogen gas and solid materials in OBGHSC and the geometrical parameters of wrapping material and liner of OBGHSC, and to developing several temperature-rise correlations. To do so, a 2-dimensional (2D) axisymmetric computational fluid dynamics (CFD) model is applied for the simulation of fast filling process and holding process of 70 MPa OBGHSC. The simulation results show that the temperature distribution during the filling is different for different type III storage cylinders, while the highest temperature is always in the head dome junction region for type IV storage cylinders. For the carbon fiber/epoxy composite laminate (CFEC), the temperature varying tendencies are not the same for different type III storage cylinders, while the temperature in type IV storage cylinder decreases with the increase of thickness of CFEC. At last, based on the obtained numerical data, the correlations for highest value of mass-averaged temperature-rise of hydrogen gas and the correlations for maximum temperature-rise of CFEC that account for the effects of dimensionless parameters are proposed. The correlations reveal the relationship between the temperature-rise and the structure of hydrogen storage cylinder and can be used to direct the fast filling process for OBHSS in this research. 相似文献
999.
AI & SOCIETY - How a social science of big data would look like? In this article, we exemplify such a social science through a number of cases. We start our discussion with the epistemic... 相似文献
1000.
Ma Mingxing Wang Zhixin Zhou Jiachen Song Meng Zhang Deliang Zhu Dachuan 《Metal Science and Heat Treatment》2022,63(9-10):470-478
Metal Science and Heat Treatment - Effect of zirconium additions on the microstructure, phase composition, microhardness and wear resistance of high-entropy AlCoCrCuFe alloys with equal mole... 相似文献