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11.
The adsorption and dissociation of O2 on Cu low-index surfaces 总被引:1,自引:0,他引:1
The extended LEPS of O(2)-Cu single crystal plane systems is constructed by means of 5-MP (the 5-parameter Morse potential). Both the adsorption and dissociation of O(2) on Cu low-index surfaces are investigated with extended LEPS in detail. All critical characteristics of the system that we obtain, such as adsorption geometry, binding energy, eigenvalues for vibration, etc., are in good agreement with the experimental results. Our calculated results suggest there are many differences between O(2)-Cu (110) and O(2)-Pd (110) systems. On a Cu (110) surface, O(2) adsorbs in a tilted configuration and there are two lowest energy dissociation channels along the [001] and [10] directions, respectively. We speculate that the adsorption geometry of O(2) on the metal surfaces relates to the lattice constant of metal. Meanwhile, We use the concepts of the molecular dissociation limit and the surface dissociation distance to analyze again the dissociation mechanism of the O(2) on the low-index surfaces. 相似文献
12.
A technique is formulated to determine both thickness and refractive indices of free-standing films with biaxial symmetry from polarized transmission spectra. The films must be transparent and show little dispersion in refractive indices in the wavelength range where the transmission spectra are collected. Methods are proposed to correct the errors caused by imperfect polarization of incident radiation and thickness variation across the sampling area. Anisotropic refractive indices and thickness of poly(biphenyl dianhydride-p-phenylenediamine) films which exhibit uniaxial optical anisotropy are determined from polarized transmission spectra. The refractive index and thickness values compare well to those obtained from waveguide prism coupler and profilometer measurements. 相似文献
13.
Diao Hongyue Deng Ansheng Cui Hui Liu Xin Zou Li 《Fuzzy Optimization and Decision Making》2022,21(1):45-69
Fuzzy Optimization and Decision Making - Linguistic information processing exists in multi-criteria decision making, and linguistic truth-valued lattice implication algebra (LTV-LIA) has definite... 相似文献
14.
A novel method for the determination of peroxynitrite using folic acid as a fluorescent probe is described. The method is based on the oxidation of the reduced, low-fluorescent folic acid by peroxynitrite to produce a high-fluorescent emission product. The fluorescence increase is linearly related to the concentration of peroxynitrite in the range of 3 × 10−8 to 5.0 × 10−6 mol L−1 with a correlation coefficient of 0.998, and the detection limit is 1 × 10−8 mol L−1. Interferences from some metal ions normally seen in biological samples, and also some anions structurally similar to peroxynitrite were studied. The optimal conditions for the detection of peroxynitrite were evaluated. 相似文献
15.
The hexaanion of fullerene, C(60)(6-), was obtained in 1:5 (v/v) acetonitrile-toluene mixture with a mercury hemispherical ultramicroelectrode as a working electrode at a temperature of up to 30 degrees C. The C(70)(6-) ion also can be observed under the same conditions. The differences between the redox potentials of C(60) relative to C(70) indicate that it is easier to add electrons to C(70) and its anions compared to the counterparts of C(60). The results show that the mercury electrode is very suitable for investigation of the properties of the electrochemical reduction for the fullerenes, particularly C(60), at room temperature. 相似文献
16.
17.
Shengbao Diao Mei Jin Jinfeng Sun Yi Zhou Chao Ye Yong Jin 《Natural product research》2019,33(5):701-707
A new diarylheptanoid, (2S,3S,5S)-2,3,5-trihydroxy-1,7-bis(4-hydroxy- 3-methoxyphenyl)heptane (1), and a new diarylheptanoid glycoside, (2S,3S,5S)-2,3-dihydroxy-5-O-β-d-xylopyranosyl-7-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)heptane (2), together with three known compounds, rhoiptelol C (3), rhoiptelol B (4) and 3′,4″-epoxy-2-O-β-d-glucopyanosyl-1-(4-hydroxyphenyl)- 7-(3-methoxyphenyl)heptan-3-one (5) were isolated from the roots of Juglans mandshurica (Juglandaceae). The structures of compounds 1 and 2 were identified based on HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Compounds 1–5 were assayed for their inhibitory effects on the production of NO, TNF-α and IL-6 in LPS-stimulated RAW264.7 cells. 相似文献
18.
Metabolic profiling of new synthetic cannabinoids AMB and 5F‐AMB by human hepatocyte and liver microsome incubations and high‐resolution mass spectrometry
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19.
Wan-Yue Diao Dan Xie Yan-Fei Li Ru Jiang Fang-Yu Tao Prof. Hai-Zhu Sun Prof. Xing-Long Wu Dr. Xiao-Ying Zhang Prof. Jing-Ping Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(31):8168-8177
Lithium metal anodes (LMAs) with high energy density have recently captured increasing attention for development of next-generation batteries. However, practical viability of LMAs is hindered by the uncontrolled Li dendrite growth and infinite dimension change. Even though constructing 3D conductive skeleton has been regarded as a reliable strategy to prepare stable and low volume stress LMAs, engineering the renewable and lithiophilic conductive scaffold is still a challenge. Herein, a robust conductive scaffold derived from renewable cellulose paper, which is coated with reduced graphene oxide and decorated with lithiophilic Au nanoparticles, is engineered for LMAs. The graphene cellulose fibres with high surface area can reduce the local current density, while the well-dispersed Au nanoparticles can serve as lithiophilic nanoseeds to lower the nucleation overpotential of Li plating. The coupled relationship can guarantee uniform Li nucleation and unique spherical Li growth into 3D carbon matrix. Moreover, the natural cellulose paper possesses outstanding mechanical strength to tolerate the volume stress. In virtue of the modulated deposition behaviour and near-zero volume change, the hybrid LMAs can achieve reversible Li plating/stripping even at an ultrahigh current density of 10 mA cm−2 as evidenced by high Coulombic efficiency (97.2 % after 60 cycles) and ultralong lifespan (1000 cycles) together with ultralow overpotential (25 mV). Therefore, this strategy sheds light on a scalable approach to multiscale design versatile Li host, promising highly stable Li metal batteries to be feasible and practical. 相似文献