Fullerols of C60 and of C70 [C60(OH)n, C70(OH)m], water-soluble fullerene derivatives, unlike some other fullerene derivatives (such as C60 (C4H6O), C60 (C3H7N) and C60 [C(COOEt)2]x), do not result in excited triplet state but in ionization via monophotonic process in aqueous solutions with 248 nm laser.
The quantum yields of formation of hydrated electron (Φe−) are determined to be 0.08 and 0.11 for fullerols of C60 and of C70 respectively at room temperature (ca. 15°C) with KI solution used as reference. By laser flash photolysis and oxidation of
sulfate radical anion SO4−, the fullerol radical cation or neutral radical of C60 is confirmed to be existent and the transient absorption spectra of fullerol radical cation of C70 are observed for the first time.
Project supported by the National Natural Science Foundation of China 相似文献
An ultra-high-performance liquid chromatography coupled with high-field quadrupole-orbitrap mass spectrometry (UHPLC-QE-MS) histological platform was used to analyze the effects of two thermal processing methods (cooking and steaming) on the nutritional metabolic components of black beans. Black beans had the most amino acids, followed by lipids and polyphenols, and more sugars. Multivariate statistical analysis indicated that heat processing significantly affected the metabolic component content in black beans, with effects varying among different components. Polyphenols, especially flavonoids and isoflavones, were highly susceptible. A total of 197 and 210 differential metabolites were identified in both raw black beans and cooked and steamed black beans, respectively. Cooking reduced the cumulative content of amino acids, lipids, polyphenols, sugars, and nucleosides, whereas steaming reduced amino acid and lipid content, slightly increased polyphenol content, and significantly increased sugar and nucleoside content. Our results indicated that metabolic components were better retained during steaming than cooking. Heat treatment had the greatest impact on amino acids, followed by polyphenols, fatty acids, sugars, and vitamins, indicating that cooking promotes the transformation of most substances and the synthesis of a few. The results of this study provide a basis for further research and development of nutritional products using black beans. 相似文献
By introducing a memristor into a chaotic system with a single non-quadratic term and substituting an absolute value function for conditional symmetry, a unique chaotic system is constructed. Firstly, the system shares a special structure of symmetry and conditional symmetry. Secondly, the amplitude and frequency of the system variables can be rescaled by the applied memristor. Interestingly it gives a new case of attractor control namely partial amplitude control and global frequency control. At last, as a new regime of extreme multistability, the memristive system shows relatively simple bifurcation according to the initial condition. This new class of chaotic system has never been reported to the best of our knowledge.
A novel Bi2O4@TiO2 heterojunction was constructed by a simple two-step method. The charges migration between Bi2O4 and TiO2 via the heterojunction improves the electron/hole separation efficiency. Furthermore, Bi2O4@TiO2 heterostructures exhibit better adsorption capability for methyl orange molecular due to their higher specific surface area than pure Bi2O4. As a result, Bi2O4@TiO2 hybrids show an improved visible light photocatalytic activity and photostability for the degradation of methyl orange. 相似文献
Porous aromatic framework materials with high stability, sensitivity, and selectivity have great potential to provide new sensors for optoelectronic/fluorescent probe devices. In this work, a luminescent porous aromatic framework material (LNU-23) was synthesized via the palladium-catalyzed Suzuki cross-coupling reaction of tetrabromopyrene and 1,2-bisphenyldiborate pinacol ester. The resulting PAF solid exhibited strong fluorescence emission with a quantum yield of 18.31%, showing excellent light and heat stability. Because the lowest unoccupied molecular orbital (LUMO) of LNU-23 was higher than that of the nitro compounds, there was an energy transfer from the excited LNU-23 to the analyte, leading to the selective fluorescence quenching with a limit of detection (LOD) ≈ 1.47 × 10−5 M. After integrating the luminescent PAF powder on the paper by a simple dipping method, the indicator papers revealed a fast fluorescence response to gaseous nitrobenzene within 10 s, which shows great potential in outdoor fluorescence detection of nitro compounds. 相似文献
Ricerche di Matematica - In this paper, we investigate a mixed fractional integral boundary value problem with p(t)-Laplacian operator. Firstly, we derive the Green function through the direct... 相似文献
Journal of Solid State Electrochemistry - A polyaniline/sulfonated graphene (PANI/SG) nanostructure was synthesized as electrode material for an asymmetric supercapacitor via a novel in situ... 相似文献