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81.
Van Loc Tran Ninh Pham Thi Thao Tran Thi Phuong Anh Tran Tuan 《Chemistry of Natural Compounds》2022,58(3):491-495
Chemistry of Natural Compounds - In this attempt to seek promising compounds from Lepisanthes rubiginosa, a widely used folk medicine in the middle of Vietnam, we isolated four compounds from the... 相似文献
82.
Nguyen Anh Triet Le Thi Phuong Ngoc Alain Pham Ngoc Dinh Nguyen Thanh Long 《Mathematical Methods in the Applied Sciences》2021,44(1):668-692
This paper is devoted to the study of a nonlinear wave equation with initial conditions and nonlocal boundary conditions of 2N‐point type, which connect the values of an unknown function u(x,t) at x = 1, x = 0, x = ηi(t) , and x = θi(t), where for all t ≥ 0. First, we prove local existence of a unique weak solution by using density arguments and applying the Banach's contraction principle. Next, under the suitable conditions, we show that the problem considered has a unique global solution u(t) with energy decaying exponentially as t → +∞ . Finally, we present numerical results. 相似文献
83.
Thao Thi Phuong Nguyen Rie Tanabe Yoshiro Ito 《Applied Physics A: Materials Science & Processing》2014,116(3):1109-1117
The effects of an absorptive coating on the dynamics of underwater laser-induced shock process have been observed from the end of laser pulse to hundreds of microseconds after irradiation by time-resolved imaging techniques. A laser pulse of 13 ns at 1,064 nm was focused by a 40-mm focal length lens onto the surface of epoxy-resin blocks immersed in water to induce the shock process in the confining regime. A custom-designed time-resolved photoelasticity imaging technique and a high-speed laser stroboscopic videography technique in photoelasticity mode were used to analyze the evolution of shock waves in the water phase, the strength of stress waves in the solid phase, the oscillation of cavitation bubbles, and the generation of bubble-collapse-induced shock waves. We showed that black paint coating enhances the strength of laser-induced stress wave inside the solid, drives faster shock waves traveling in the water phase, and produces higher-energy cavitation bubbles. We propose that even at power densities of 1 GW/cm2 and above, an absorptive coating can intensify the shock process by enhancing the absorption of laser energy by plasma. 相似文献
84.
D. T. Binh L. T. Hue D. T. Huong H. N. Long 《The European Physical Journal C - Particles and Fields》2014,74(5):1-18
We re-investigate the scalar potential and the Higgs sector of the supersymmetric economical 3-3-1 model (SUSYE331) in the presence of the $B/\mu $ -type terms, which has many important consequences. First, the model contains no massless Higgs fields. Second, we prove that the soft mass parameters of the Higgses must be at the $\hbox {SU}(3)_L$ scale. As a result, the masses of the Higgses drift toward this scale except one light real neutral Higgs with the mass of $m_Z|c_{2\gamma }|$ at the tree level. We also show that there are some Higgses containing many properties of the Higgses in the minimal supersymmetric standard model (MSSM), especially in the neutral Higgs sector. One exact relation in the MSSM, $m^2_{H^{\pm }}=m^2_{A}+m^2_W$ , is still true in the SUSYE331. Based on this result we make some comments on the lepton flavor violating decays of these Higgses as one of signatures of new physics in the SUSYE331 model which may be detected by present colliders. 相似文献
85.
Le Thi Phuong Ngoc Nguyen Thanh Long 《Mathematical Methods in the Applied Sciences》2014,37(4):464-487
This paper is devoted to the study of a system of nonlinear equations with nonlinear boundary conditions. First, on the basis of the Faedo–Galerkin method and standard arguments of density corresponding to the regularity of initial conditions, we establish two local existence theorems of weak solutions. Next, we prove that any weak solutions with negative initial energy will blow up in finite time. Finally, the exponential decay property of the global solution via the construction of a suitable Lyapunov functional is presented. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
86.
To measure the transport of vibrational energy along a peptide helix, Hamm and co-workers [J. Phys. Chem. B 112, 9091 (2008)] performed time-resolved vibrational experiments, which showed that the energy transport rate increases by at least a factor of 4, when a localized C=O mode of the peptide instead of an attached chromophore is excited. This finding raises the question if coherent excitonic energy transfer between the C=O modes may be of importance for the overall energy transport in peptides. With this idea in mind, nonequilibrium molecular dynamics simulations as well as quantum-classical calculations are performed, which qualitatively reproduce the experimental findings. Moreover, the latter model (an exciton Hamiltonian whose matrix elements depend on the instantaneous positions of the peptide and solvent atoms) indeed exhibits the signatures of coherent quantum energy transport, at least within the first few picoseconds and at low temperatures. The origin of the observed decoherence, the absence of vibrational self-trapping, and the possibility of quantum interference between various transport paths are discussed in some detail. 相似文献
87.
D.B. Phuong Huynh David J. Knezevic Anthony T. Patera 《Comptes Rendus Mathematique》2011,349(7-8):401-405
We present a certified reduced basis (RB) method for the heat equation and wave equation. The critical ingredients are certified RB approximation of the Laplace transform; the inverse Laplace transform to develop the time-domain RB output approximation and rigorous error bound; a (Butterworth) filter in time to effect the necessary “modal” truncation; RB eigenfunction decomposition and contour integration for Offline–Online decomposition. We present numerical results to demonstrate the accuracy and efficiency of the approach. 相似文献
88.
Van Trang Nguyen Dung Tran Ngoc Van Duong Long Pham-Ho My Phuong Nguyen Hue Minh Thi Nguyen Minh Tho 《Structural chemistry》2020,31(6):2215-2225
Structural Chemistry - Structural, electronic, and optical properties of a series of organic semiconductors based on dithienosilole (DTS) and its derivatives were theoretically studied using... 相似文献
89.
Nguyen Tien Cong Huynh Thi Xuan Trang Pham Duc Dung Tran Hoang Phuong Vu Quoc Trung Nguyen Dang Dat Dang Thi Tuyet Anh Nguyen Van Tuyen Luc Van Meervelt 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(9):874-882
Five 2‐aroyl‐5‐bromobenzo[b]furan‐3‐ol compounds (two of which are new) and four new 2‐aroyl‐5‐iodobenzo[b]furan‐3‐ol compounds were synthesized starting from salicylic acid. The compounds were characterized by mass spectrometry and 1H NMR and 13C NMR spectroscopy. Single‐crystal X‐ray diffraction studies of four compounds, namely, (5‐bromo‐3‐hydroxybenzofuran‐2‐yl)(4‐fluorophenyl)methanone, C15H8BrFO3, (5‐bromo‐3‐hydroxybenzofuran‐2‐yl)(4‐chlorophenyl)methanone, C15H8BrClO3, (5‐bromo‐3‐hydroxybenzofuran‐2‐yl)(4‐bromophenyl)methanone, C15H8Br2O3, and (4‐bromophenyl)(3‐hydroxy‐5‐iodobenzofuran‐2‐yl)methanone, C15H8BrIO3, were also carried out. The compounds were tested for their in vitro cytotoxicity on the four human cancer cell lines KB, Hep‐G2, Lu‐1 and MCF7. Six compounds show good inhibiting abilities on Hep‐G2 cells, with IC50 values of 1.39–8.03 µM. 相似文献
90.
Dr. Thi‐Phuong‐Anh Cao Dr. Grégory Nocton Dr. Louis Ricard Dr. Xavier F. Le Goff Dr. Audrey Auffrant 《Angewandte Chemie (International ed. in English)》2014,53(5):1368-1372
The oxidation of a NiII complex bearing a tetradentate phosphasalen ligand, which differs from salen by the presence of an iminophosphorane (P?N) in place of an imine unit, was easily achieved by addition of a silver salt. The site of this oxidation was investigated with a combination of techniques (NMR, EPR, UV/Vis spectroscopy, X‐ray diffraction, magnetic measurements) as well as DFT calculations. All data are in agreement with a high‐valent NiIII center concentrating the spin density. This markedly differs from precedents in the salen series for which oxidation on the metal was only observed at low temperature or in the presence of additional ligands or anions. Therefore, thanks to the good electron‐donating properties of the phosphasalen ligand, [Ni(Psalen)]+ represents a rare example of a tetracoordinated high‐valent nickel complex in presence of a phenoxide ligand. 相似文献