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101.
Neng Zhang Zhao-Chun Zhang Jian-Gang Zhou 《Journal of Sol-Gel Science and Technology》2011,58(2):355-359
Calcium stannate (CaSnO3) nanofibers were synthesized by electrospinning technique combined with a sol–gel process. The structure and morphology of
the as-prepared CaSnO3 nanofibers were characterized by X-ray diffraction and scanning electron microscopy, respectively. The samples had a band
gap of about 3.87 eV, which was estimated by UV–Vis diffuse reflectance spectroscopy. On the basis of the experiment results,
the composite fibers containing polymer and inorganic salt can be changed to pure CaSnO3 nanofibers only when they were sintered at an appropriate temperature. At the same time, a possible mechanism of the nanofibers
forming process was also proposed. 相似文献
102.
Ya‐Ling Liu Pei Zou Hao Wu Min‐Hao Xie Shi‐Neng Luo 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(9):o338-o340
The title compound, C16H24O10·0.11H2O, is a key intermediate in the synthesis of 2‐deoxy‐2‐[18F]fluoro‐d ‐glucose (18F‐FDG), which is the most widely used molecular‐imaging probe for positron emission tomography (PET). The crystal structure has two independent molecules (A and B) in the asymmetric unit, with closely comparable geometries. The pyranose ring adopts a 4C1 conformation [Cremer–Pople puckering parameters: Q = 0.553 (2) Å, θ = 16.2 (2)° and ϕ = 290.4 (8)° for molecule A, and Q = 0.529 (2) Å, θ =15.3 (3)° and ϕ = 268.2 (9)° for molecule B], and the dioxolane ring adopts an envelope conformation. The chiral centre in the dioxolane ring, introduced during the synthesis of the compound, has an R configuration, with the ethoxy group exo to the mannopyranose ring. The asymmetric unit also contains one water molecule with a refined site‐occupancy factor of 0.222 (8), which bridges between molecules A and B via O—H...O hydrogen bonds. 相似文献
103.
104.
Neng‐Xiu Zhu Zhang‐Wen Wei Cheng‐Xia Chen Dawei Wang Chen‐Chen Cao Qian‐Feng Qiu Ji‐Jun Jiang Hai‐Ping Wang Cheng‐Yong Su 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(47):17189-17196
We transformed the hydrophilic metal–organic framework (MOF) UiO‐67 into hydrophobic UiO‐67‐R s (R=alkyl) by introducing alkyl chains into organic linkers, which not only protected hydrophilic Zr6O8 clusters to make the MOF interspace superoleophilic, but also led to a rough crystal surface beneficial for superhydrophobicity. The UiO‐67‐R s displayed high acid, base, and water stability, and long alkyl chains offered better hydrophobicity. Good hydrophobicity/oleophilicity were also possible with mixed‐ligand MOFs containing metal‐binding ligands. Thus, a (super)hydrophobic MOF catalyst loaded with Pd centers efficiently catalyzed Sonogashira reactions in water at ambient temperature. Studies of the hydrophobic effects of the coordination interspace and the outer surface suggest a simple de novo strategy for the synthesis of superhydrophobic MOFs that combine surface roughness and low surface energy. Such MOFs have potential for environmentally friendly catalysis and water purification. 相似文献
105.
The Inert Doublet Model(IDM) is one of the many beyond Standard Model scenarios with an extended scalar sector, which provide a suitable dark matter particle candidate. Dark matter associated visible particle production at high energy colliders provides a unique way to determine the microscopic properties of the dark matter particle. In this paper, we investigate that the mono-W + missing transverse energy production at the Large Hadron Collider(LHC),where W boson decay to a lepton and a neutrino. We perform the analysis for the signal of mono-W production in the IDM and the Standard Model(SM) backgrounds, and the optimized criteria employing suitable cuts are chosen in kinematic variables to maximize signal significance. We also investigate the discovery potential in several benchmark scenarios at the 14 TeV LHC. When the light Z_2 odd scalar higgs of mass is about 65 GeV, charged Higgs is in the mass range from 120 GeV to 250 GeV, it provides the best possibility with a signal significance of about 3σ at an integrated luminosity of about 3000 fb~(-1). 相似文献
106.
关于复正定矩阵行列式的不等式 总被引:1,自引:1,他引:0
金能 《数学的实践与认识》2000,30(4)
本文讨论了复正定矩阵行列式的估计式 ,修正了文 [2 ]的一些错误 ,得到了一些复正定矩阵行列式的不等式 . 相似文献
107.
Neng‐Wu Zheng Yu‐Jie Sun Tao Wang Dong‐Xia Ma Yi Zhang Wei Su 《International journal of quantum chemistry》2000,76(1):51-61
One of us has presented a new theory called the Weakest Bound Electron Potential Model theory (WBEPM theory) to determine the exact potential field in atoms. A concise analytic form of the potential of the weakest‐bound electron is proposed. In the new potential and the wave function derived afterward, the integral atomic number Z and quantum numbers n and l are replaced by nonintegral Z*, n*, and l*, respectively. In this article, we employed the WBEPM theory to calculate the transition probability for the lithium atom and lithiumlike ions and obtained very good results compared with the accepted values and other results. © 1999 John Wiley & Sons, Inc. Int J Quant Chem 76: 51–61, 2000 相似文献
108.
109.
Neng Wu Zheng Yujie Sun Dongxia Ma Ruyi Yang Tao Zhou Tao Wang 《International journal of quantum chemistry》2001,81(3):232-237
Within the scheme of the weakest bound electron potential model theory, the regularity of changes in quantum defects in 40 “spectrum‐level‐like series” of several many‐valence electron atoms of the third period was studied. The n–δ curves of the 40 spectrum‐level‐like series could be classified into three types; for all such series the quantum defects δ could be expanded as a polynomial of the principal quantum number n in a spectrum‐level‐like series. With regularity, the level energies of high Rydberg states in a series can be predicted accurately. By carefully studying and explaining the three types of 40 n–δ curves, the conclusion was reached: the type of the n–δ curve, i.e., the regularity of changes in quantum defects in a spectrum‐level‐like series, was determined by both the energy level and the azimuthal quantum number l of the weakest bound electron. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 81: 232–237, 2001 相似文献
110.