| 1. |
- Song, Xiu-Neng, et al.
(författare)
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Theoretical Identification of Three C-66 Fullerene Isomers and Related Chlorinated Derivatives by X-ray Photoelectron Spectroscopy and Near-edge X-ray Absorption Fine Structure Spectroscopy
- 2016
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Ingår i: JOURNAL OF PHYSICAL CHEMISTRY A. - : American Chemical Society (ACS). - 1089-5639 .- 1520-5215. ; 120:50, s. 9932-9940
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Tidskriftsartikel (refereegranskat)abstract
- C is X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectra for three C-66 fullerene isomers and related chlorinated species have been calculated by density functional theory (DFT) method. The XPS spectra show isomer dependence for the three, pristine C-66 isomers but not for the chlorinated species. The NEXAFS spectra exhibit strong dependence on the structures of all the investigated molecules and thus can be well employed to identify the three C-66 fullerene isomers and related chlorinated species. Both XPS and NEXAFS spectra of the chlorinated species present significant variations compared with the pristine fullerenes. The spectral components for carbon atoms of different local environments have been explored as well. The spectra for the carbon atoms connecting to chlorine atoms exhibit a significant blue shift compared to the others.
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| 2. |
- Wang, Guang-Wei, et al.
(författare)
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Theoretical Isomer Identification of Three C-56 Fullerenes and Their Chlorinated Derivatives by XPS and NEXAFS Spectra
- 2016
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 120:25, s. 13779-13786
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Tidskriftsartikel (refereegranskat)abstract
- The C Is X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy for three C-56 fullerene isomers and their chlorinated derivatives have been theoretically simulated by means of density functional theory (DFT). Compared with XPS, the NEXAFS spectra present remarkable dependence on the structures of all the studied molecules and thus can be used to identify the three C-56 isomers and chlorinated species. The spectra of the chlorinated species present significant variations compared with the pristine fullerenes. The spectral components of carbon atoms of different local environment have been investigated as well. The spectra of carbons saturated by chlorine atoms exhibit a shift toward higher energies compared with the others.
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| 3. |
- Zhao, Cheng-Shou, et al.
(författare)
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Thermal decomposition behaviors of a self-intumescent flame retardant epoxy resin
- 2022
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Ingår i: Journal of Applied Polymer Science. - : John Wiley & Sons. - 0021-8995 .- 1097-4628. ; 139:18
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Tidskriftsartikel (refereegranskat)abstract
- This paper focuses on revealing the thermal decomposition behaviors of a self-intumescent flame retardant (IFR) epoxy (EP) resin (EP/15%APP-Cu2O) employing 12 wt% ammonium polyphosphate (APP) as a halogen-free flame retardant and 3 wt% copper (I) oxide (Cu2O) as char forming rate regulator. Initially, the thermal stability of EP/15%APP-Cu2O was analyzed and compared to virgin EP resin and flame retardant EP (EP/15%APP) containing 15 wt% APP as flame retardant by thermogravimetric analysis test at different heating rates under nitrogen atmosphere. It was shown that the incorporation of APP altered the decomposition pathway of EP and decreased the onset decomposition temperature. Luckily, compared to EP/15%APP, the onset decomposition temperature of EP/15%APP-Cu2O was just slightly reduced from 300.4 to 292.8 degrees C. Then, the thermal degradation kinetics of EP, EP/15%APP and EP/15%APP-Cu2O were further evaluated by Kissinger and Flynn-Wall-Ozawa methods. It was worth noted that the addition of APP or APP-Cu2O enhanced the thermal degradation activation energies of EP, which contributed to the protective effect of the char formation. Particularly, the incorporation of 3 wt% Cu2O significantly decreased the thermal degradation activation energies at the early decomposition stage of EP. This may be the main contribution for intumescent char formation, which resulted in higher fire safety of EP/15%APP-Cu2O compared to EP/15%APP. These information can potentially help to develop alternative IFR systems.
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