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21.
Nguyen Dinh Phu Le Thanh Quang Tran Thanh Tung 《Nonlinear Analysis: Theory, Methods & Applications》2008
The existence and comparison results on solutions of set control differential equation were studied in [N.D. Phu, T.T. Tung, Some results on sheaf-solutions of sheaf set control problems, Nonlinear Analysis 67 (2007) 1309–1315]. In this paper, we present the stability criteria for solutions of set control differential equation. 相似文献
22.
In this article we construct link invariants and 3-manifold invariants from the quantum group associated with the Lie superalgebra \(\mathfrak {sl}(2|1)\). The construction is based on nilpotent irreducible finite dimensional representations of quantum group \(\mathcal {U}_{\xi }\mathfrak {sl}(2|1)\) where \(\xi \) is a root of unity of odd order. These constructions use the notion of modified trace and relative \( G \)-modular category of previous authors. 相似文献
23.
Cong Truc Huynh Minh Khanh Nguyen Dai Phu Huynh Doo Sung Lee 《Colloid and polymer science》2011,289(3):301-308
Biodegradable star-shaped copolymers comprised of four-arm poly(ethylene glycol) (4-arm PEG) and poly(β-amino ester) (PAE)
were synthesized by conjugating PAE to 4-arm PEG. The synthesized copolymers were characterized by 1H and 13C NMR and gel permeation chromatography. The PAE showed pH/temperature-sensitive properties in an aqueous solution. The copolymer
solutions (30 wt.%) showed a gel-to-sol phase transition as a function of temperature in the pH range 7.2–7.8. The gel window
covers the physiological conditions (37 °C and pH 7.4) and can be controlled by varying the PAE block length, copolymer solution
concentration and PEG molecular weight. After a subcutaneous injection of the copolymer solution into a SD rat, a gel formed
rapidly in situ which remained for more than 2 weeks in the body. This copolymer is expected to be a potential candidate for
biomedical applications. 相似文献
24.
M. Sylla D. Rou de R. Chevalier X. Nguyen Phu G. Rivoire 《Optics Communications》1992,90(4-6):391-398
We have observed a very strong nonlinear absorption in BSO and BGO crystals when they are illuminated by picosecond laser pulses with optical intensity on the order of 108 W/cm2. In addition, a phase conjugate reflectivity of 2×10-3 is obtained in a degenerate four-wave mixing (DFWM) experiment using the same optical power. We derive the nonlinear coupled-wave equations to explain the experimental results. We show that the creation of the conjugate wave can be explained by the presence of a strong nonlinear absorption. 相似文献
25.
Degenerate four wave mixing is produced by the single pulse of a mode locked laser (duration 25 ps). The intensities are measured. The feasibility of image reconstruction is proved, and methods for time measurements (pulse durations, relaxation times) are proposed. 相似文献
26.
Francesco Boschetto Hoan Ngoc Doan Phu Phong Vo Matteo Zanocco Kenta Yamamoto Wenliang Zhu Tetsuya Adachi Kenji Kinashi Elia Marin Giuseppe Pezzotti 《Molecules (Basel, Switzerland)》2021,26(10)
The present work investigated the effect of Polylactic acid (PLA) fibers produced by centrifugal spinning with incorporated BaTiO3 particles to improve their bacteriostatic behavior. The PLA matrix and three composites, presenting three different amounts of fillers, were subjected to UV/O3 treatment monitoring the possible modifications that occurred over time. The morphological and physical properties of the surfaces were characterized by different microscopic techniques, contact angle, and surface potential measurements. Subsequently, the samples were tested in vitro with human dermal fibroblasts (HDF) to verify the cytotoxicity of the substrates. No significant differences between the PLA matrix and composites emerged; the high hydrophobicity of the fibers, derived by the polymer structure, represented an obstacle limiting the fibroblast attachment. Samples underwent bacterial exposure (Staphylococcus epidermidis) for 12 and 24 h. Increasing the concentration of BT, the number of living bacteria and their distribution decreased in comparison with the PLA matrix suggesting an effect of the inorganic filler, which generates a neutralization effect leading to reactive oxygen species (ROS) generation and subsequently to bacterial damages. These results suggest that the barium titanate (BT) fillers clearly improve the antibacterial properties of PLA fibers after aging tests made before bacterial exposure, representing a potential candidate in the creation of composites for medical applications. 相似文献
27.
N. S. Bredov Le Phu Soan V. V. Kireev A. A. Bykovskaya I. B. Sokol’skaya M. V. Gorlov A. S. Esin S. R. Bekmukhamedova V. A. Polyakov 《Polymer Science Series B》2017,59(3):240-247
Methacrylate-containing oligosilsesquioxanes with a molecular mass of 700–4000 are synthesized via the acidic hydrolytic polycondensation of γ-methacryloxy-propyltrimethoxysilane (A-174) in the medium of methyl methacrylate or in a mixture of bis(methacrylates). The structure of the oligomers is studied by 1Н and 29Si NMR spectroscopy and MALDI-TOF mass spectrometry. 相似文献
28.
Nhi Y. T. Nguyen Phu H. Dang Van T. T. Nguyen Quan L. Tran 《Natural product research》2019,33(13):1903-1908
From an EtOAc-soluble fraction of the leaves of Azadirachta indica, one new lactam 28-norlimonoid named nimbandiolactam-21 (1), together with 2 known limonoids (2 and 3) were isolated. Their relative structures were elucidated based on NMR spectroscopic analysis. Nimbandiolactone-23 (2) showed the most potent α-glucosidase inhibitory activity, with an IC50 value of 38.7 μM. Compound 1 represents the first naturally occurring example of a 28-norlimonoid having the lactam moiety. The plausible biosynthetic pathway for the formation of lactam moiety in 1 was proposed. 相似文献
29.
In a new picosecond phase conjugation experiment, an optical triggered switching effect has been observed in backscattering. Comparison with an almost similar configuration used in a nanosecond experiment shows significant differences, which can be explained by the small duration of the pulse. 相似文献
30.
Akira Ishimaru Jei S. Chen Phillip Phu Kuniaki Yoshitomi 《Waves in Random and Complex Media》1991,1(3):S91-S107
This paper Presents numerical simulations, theoretical analysis, and millimeter wave experiments for scattering from one-dimensional very rough surfaces. First, numerical simulations are used to investigate the effects of roughness spectrum, height variation, interface medium, polarization, and incident angle on the backscattering enhancement. The enhanced backscattering due to rough surface scattering is divided into two cases; the RMS height close to a wavelength and RMS slope close to unity, and RMS height much smaller than a wavelength with surface wave contributions. Results also show that the enhancement is sensitive to the roughness spectrum. Next, a theory based on the first- and second-order Kirchhoff approximation modified with angular and propagation shadowing is developed. The theoretical solutions provide a physical explanation of backscattering enhancement and agree well with the numerical results. In addition to the scattering of a monochromatic wave, the analytical results of the broadening and lateral spreading of a pulsed beam wave scattering from rough surfaces are also discussed. Finally, the existence of backscattering enhancement from one-dimensional very rough conducting surfaces with exact Gaussian statistics and Gaussian roughness spectrum is verified by a millimeter-wave experiment. Experimental results which show enhanced backscattering for both TE and TM polarizations for different angles of incidence are presented. 相似文献