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81.
82.
In the large momentum transfer limit, generalized parton distributions can be calculated through a QCD factorization theorem which involves perturbatively calculable hard kernels and light-cone parton distribution amplitudes of hadrons. We illustrate this through the H(q)(x,xi,t) distribution for the pion and the proton, presenting the hard kernels at leading order. As a result, experimental data on the generalized parton distributions in this regime can be used to determine the functional form of the parton distribution amplitudes which has thus far been quite challenging to obtain. Our result can also be used as a constraint in phenomenological generalized parton distribution parametrizations. 相似文献
83.
Ethynylated phenothiazine based fluorescent boronic acid probes were prepared. Sonogashira coupling reaction was used to introduce
substituted phenylethynylene fragments to the phenothiazine fluorophore to extend the π-conjugation and to enhance the emission
property. The photophysical properties and the binding properties of these probes with hydroxyl acids were investigated. We
found that the probes with significant ICT effect show emissions which are sensitive to solvent polarity. The phenothiazine
moiety is proved to be electron-donating. We found the substitution profile imparts significant effect on the photophysical
properties of the probes. For example, one of the probes shows d-PeT effect, whereas the regioisomer probe with similar π-conjugation
fragment but different substitution profile shows the a-PeT effect. The easy derivatization of phenothiazine fluorophore,
the structure-photophysical property relation and the novel d-PeT fluorescence transduction profile of the phenothiazine based
probes described herein may inspire more investigation into this fascinating research area. 相似文献
84.
The hitherto analyses of elastic collisions of charged nucleons involving common influence of Coulomb and hadronic scattering have been based practically on West and Yennie formula. However, this approach has been shown recently to be inadequate from experimental as well as theoretical points of view. The eikonal model enabling to determine physical characteristics in impact parameter space seems to be more pertinent. The contemporary phenomenological models admit, of course, different distributions of collision processes in the impact parameter space and cannot give any definite answer. Nevertheless, some predictions for the planned LHC energy that have been given on their basis may be useful, as well as the possibility of determining the luminosity from elastic scattering. 相似文献
85.
Qinyu Wang Qifang Lu Xueyang Ji Zhendong Liu Mingzhi Wei Enyan Guo 《Journal of nanoparticle research》2017,19(6):222
One-dimensional Bi2MoxW1-xO6 (x = 0, 0.2, 0.5, 0.67, and 1) photocatalysts have been successfully synthesized for the first time by a straightforward electrospinning technique with a calcination process. The as-formed Bi2MoxW1-xO6 nanofibers are composed of inter-linked nanosheets of 30–50 nm in size and characterized by thermogravimetric and differential scanning calorimetric, Fourier transform infrared, Raman spectra, X-ray powder diffraction, scanning electron microscope, Brunauer-Emmett-Teller, transmission electron microscope, UV-Vis spectroscopy, photoluminescence, HPLC, and EIS. The photodegradation behaviors towards organic dyes, including rhodamine B (RhB) and methylene blue (MB) are investigated, and the results illustrate that Bi2Mo0.25W0.75O6 nanofibers exhibit the highest photocatalytic performance under visible light irradiation than Bi2MoxW1-xO6 (x = 0, 0.2, 0.5, 0.67, and 1) samples. The possible mechanisms of the enhanced photocatalytic properties are discussed in detail. 相似文献
86.
Lin Zhang Ying-Hua LiYu-Ying Yu Xue-Mei LiYun Ma Cheng-Gang GuCheng-Da Dai Ling-Cang Cai 《Physica B: Condensed Matter》2011,406(22):4163-4169
The mean-field potential (MFP) approach is an efficient way to evaluate the free energy contribution of ion motions for both solid and liquid states. In this paper the MFP is generally constructed with a volume-dependent term and a shape function. The former is derived in accordance with quasi-harmonic approximation. The latter is given semi-empirically. Application to multiphase equations of state for β-, γ- and liquid-tin has been examined. The theoretical phase diagram and thermodynamic properties of isotherm, thermal expansion, heat capacity, Hugoniot states as well as phase transitions are all in excellent agreement with experiments. 相似文献
87.
Katharina Zielke Ondřej Kováč Michael Winter Dr. Jiří Pospíšil Prof. Mario Waser 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(34):8163-8168
The first highly asymmetric catalytic synthesis of densely functionalized dihydrobenzofurans is reported, which starts from ortho-hydroxy-containing para-quinone methides. The reaction relies on an unprecedented formal [4+1]-annulation of these quinone methides with allenoates in the presence of a commercially available chiral phosphine catalyst. The chiral dihydrobenzofurans were obtained as single diastereomers in yields up to 90 % and with enantiomeric ratios up to 95:5. 相似文献
88.
Dr. Sanil E. Sivan Minhui Lee Su-Kyung Lee Dr. Ji Woong Yoon Dr. Kiwoong Kim Dr. Do-Young Hong Kyung-Ho Cho Dr. U-Hwang Lee Prof. Jong-San Chang Dr. Jaehoon Jung Prof. Young Kyu Hwang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(56):12889-12894
Oxo-bridged trimeric chromium acetate clusters [Cr3O(OOCCH3)6(H2O)3]NO3 have been encapsulated for the first time in the mesoporous cages of the chromium terephthalate MIL-101(Cr). The isolated clusters in MIL-101(Cr) have increased affinity towards propylene compared to propane, due to generation of a new kind of pocket-based propylene-binding site, as supported by DFT calculations. 相似文献
89.
Yong Zhang Min Yang Chengli Jia Prof. Min Ji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(60):13709-13713
A method for the synthesis of novel fused four-ring quinoxaline skeleton has been described by an I2 promoted sp3 C−H functionalization between 1,2,3,3-tetramethyl-3H-indolium iodides and 1,2-diamines. This transformation proceeds smoothly under metal- and peroxide-free conditions through a sequential iodination, oxidation, annulation and rearrangement. Moreover, 8,9-dichloro-5,12,12-trimethyl-2-(trifluoromethyl)-5,12-dihydroquinolino[2,3-b]quinoxaline showed good photophysical properties and was used in live cell imaging, indicating the potential value of this skeleton as a fluorophore in probes. 相似文献
90.