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1.
陈华俊  朱鹏杰  陈咏雷  侯宝成 《中国物理 B》2022,31(2):27802-027802
We investigate theoretically Rabi-like splitting and Fano resonance in absorption spectra of quantum dots(QDs)based on a hybrid QD-semiconducting nanowire/superconductor(SNW/SC)device mediated by Majorana fermions(MFs).Under the condition of pump on-resonance and off-resonance,the absorption spectrum experiences the conversion from Fano resonance to Rabi-like splitting in different parametric regimes.In addition,the Fano resonances are accompanied by the rapid normal phase dispersion,which will indicate the coherent optical propagation.The results indicate that the group velocity index is tunable with controlling the interaction between the QD and MFs,which can reach the conversion between the fast-and slow-light.Fano resonance will be another method to detect MFs and our research may indicate prospective applications in quantum information processing based on the hybrid QD-SNW/SC devices.  相似文献   
2.
Chen  Yujie  Sang  Weixuan  Chen  Rong  Liu  Xue  Li  Xiaoyan  Guan  Fenfen  Li  Xun  Xiao  Hui 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):367-373
Journal of Radioanalytical and Nuclear Chemistry - The nanoscale zero-valent nickel (nano-Ni0) was prepared by liquid-phase reduction method and characterized by BET, XPS, FT-IR and XRD and be used...  相似文献   
3.
Studies on N2 activation and transformation by transition metal hydride complexes are of particular interest and importance. The synthesis and diverse transformations of a dinitrogen dititanium hydride complex bearing the rigid acridane-based acriPNP-pincer ligands {[(acriPNP)Ti]2(μ2-η1:η2-N2)(μ2-H)2} are presented. This complex enabled N2 cleavage and hydrogenation even without additional H2 or other reducing agents. Furthermore, diverse transformations of the N2 unit with a variety of organometallic compounds such as ZnMe2, MgMe2, AlMe3, B(C6F5)3, PinBH, and PhSiH3 have been well established at the rigid acriPNP-ligated dititanium framework, such as reversible bonding-mode change between the end-on and side-on/end-on fashions, diborylative N=N bond cleavage, the formal insertion of two dimethylaluminum species into the N=N bond, and the formal insertion of two silylene units into the N=N bond. This work has revealed many unprecedented aspects of dinitrogen reaction chemistry.  相似文献   
4.
Han  Jing  Sun  Youhong  Guo  Wei  Deng  Sunhua  Hou  Chuanbin  Qu  Lili  Li  Qiang 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2287-2296
Journal of Thermal Analysis and Calorimetry - In this study, the non-isothermal pyrolysis method was used to investigate the pyrolysis characteristics of oil shale from four areas: namely Nongan,...  相似文献   
5.
The N–N bond is present in many important organic compounds, such as hydrazines, pyrazoles, azos, etc. Many methods based on transition metal catalyzed N–N coupling or functionalization of hydrazine have been reported for the synthesis of N–N containing organic compounds. In recent years, electrochemical dehydrogenative N–H/N–H coupling has become a powerful tool for the construction of N–N bearing organic compounds. The electrochemical methods employ electrons as traceless redox reagents instead of chemicals and produce hydrogen as the only byproduct. In this review, we summarize the recent advances in the electrochemical dehydrogenative N–H/N–H coupling reactions with focus on the mechanistic insights and synthetic applications of these transformations.  相似文献   
6.
CeO2-based catalysts are widely studied in catalysis fields. Developing one novel synthetic approach to increase the intimate contact between CeO2 and secondary species is of particular importance for enhancing catalytic activities. Herein, an interfacial reaction between metal–organic framework (MOF)-derived carbon and KMnO4 to synthesize CeO2−MnO2, in which carbon is derived from the pyrolysis of Ce-MOFs under an inert atmosphere, is described. The MOF-derived carbon is found to restrain the growth of CeO2 crystallites under a high calcination temperature and, more importantly, intimate contact within CeO2/C is conveyed to CeO2/MnO2 after the interfacial reaction; this is responsible for the high catalytic activity of CeO2−MnO2 towards CO oxidation.  相似文献   
7.
Journal of Radioanalytical and Nuclear Chemistry - Determination of long-lived radionuclides is critical for environmental radioactivity investigation, environmental processes studies and...  相似文献   
8.
Tetrathiatriarylmethyl (TAM, trityl) radicals have found wide applications as spin probes/labels for EPR spectroscopy and imaging, and as polarizing agents for dynamic nuclear polarization. The high hydrophilicity of TAM radicals is essential for their biomedical applications. However, the synthesis of hydrophilic TAM radicals (e.g., OX063) is extremely challenging and has only been reported in the patent literature, to date. Herein, an efficient synthesis of a highly water-soluble TAM radical bis(8-carboxyl-2,2,6,6-tetramethylbenzo[1,2-d:4,5-d′]bis([1,3]dithiol-4-yl)-mono-(8-carboxyl-2,2,6,6-tetrakis(2-hydroxyethyl)benzo[1,2-d:4,5-d′]bis([1,3]dithiol-4-yl)methyl (TFO), which contains four additional hydroxylethyl groups, relative to the Finland trityl radical CT-03, is reported. Similar to OX063, TFO exhibits excellent properties, including high water solubility in phosphate buffer, low log P, low pKa, long relaxation times, and negligible binding with bovine serum albumin. On the other hand, TFO has a sharper EPR line and higher O2 sensitivity than those of OX063. Therefore, in combination with its facile synthesis, TFO should find wide applications in magnetic resonance related fields and this synthetic approach would shed new light on the synthesis of other hydrophilic TAM radicals.  相似文献   
9.
Inorganic planar ring-shape molecules with 4n + 2 π electrons are always the focus of experimental synthesis and theoretical research due to their potential aromaticity and stability. In this work, the whole series of five-membered heterocycle monoanions X nY5-n (X, Y = group 15 elements; n = 1-4) were thoroughly investigated by means of density functional theory calculations. They all have large formation energies and HOMO-LUMO gap energies, suggesting the potential thermodynamic and kinetic stability. Their aromaticities are comparable to that of typical aromatic hydrocarbons. Their thermal stabilities were firmly established by the ab initio molecular dynamics simulations. As most of them are predicted for the first time, their various spectra were simulated for experimental characterization. Furthermore, we demonstrate that these five-membered cyclic anions can be employed as η5-ligand to construct novel all-inorganic metallocenes, which may serve as the building blocks of low-dimensional nanomaterials.  相似文献   
10.
Semiconductor metal oxides (SMO)-based gas-sensing materials suffer from insufficient detection of a specific target gas. Reliable selectivity, high sensitivity, and rapid response–recovery times under various working conditions are the main requirements for optimal gas sensors. Chemical warfare agents (CWA) such as sarin are fatal inhibitors of acetylcholinesterase in the nerve system. So, sensing materials with high sensitivity and selectivity toward CWA are urgently needed. Herein, micro-nano octahedral Co3O4 functionalized with hexafluoroisopropanol (HFIP) were deposited on a layer of reduced graphene oxide (rGO) as a double-layer sensing materials. The Co3O4 micro-nano octahedra were synthesized by direct growth from electrospun fiber templates calcined in ambient air. The double-layer rGO/Co3O4-HFIP sensing materials presented high selectivity toward DMMP (sarin agent simulant, dimethyl methyl phosphonate) versus rGO/Co3O4 and Co3O4 sensors after the exposure to various gases owing to hydrogen bonding between the DMMP molecules and Co3O4-HFIP. The rGO/Co3O4-HFIP sensors showed high stability with a response signal around 11.8 toward 0.5 ppm DMMP at 125 °C, and more than 75 % of the initial response was maintained under a saturated humid environment (85 % relative humidity). These results prove that these double-layer inorganic–organic composite sensing materials are excellent candidates to serve as optimal gas-sensing materials.  相似文献   
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