Bright soliton solutions of the (2+1)-dimensional generalized coupled nonlinear Schrödinger equation with the four-wave mixing term

Nonlinear Dynamics - The (2+1)-dimensional generalized coupled nonlinear Schrödinger equation with the four-wave mixing (FWM) term is studied in this paper, which describes the optical...     

QSPR study for the prediction of half-wave potentials of benzoxazines by heuristic method and radial basis function neural network

The half-wave potential (E_1/2) is an important electrochemical property of organic compounds. In this work, a quantitative structure-property relationship (QSPR) analysis has been conducted on the half-wave reduction potential (E_1/2) of 40 substituted benzoxazines by means of both a heuristic method (HM) and a non-linear radial basis function neural network (RBFNN) modeling method. The statistical parameters provided by the HM model (R² =0.946; F=152.576; RMSCV=0.0141) and the RBFNN model (R²=0.982; F=1034.171 and RMS =0.0209) indicated satisfactory stability and predictive ability. The obtained models showed that benzoxazines with larger Min valency of a S atom (MVSA), lower Relative number of H atom (RNHA) and Min n-n repulsion for a C-H bond (MnnRCHB) and Minimal Electrophilic Reactivity Index for a C atom (MERICA) can be more easily reduced. This QSPR approach can contribute to a better understanding of structural factors of the organic compounds that contribute to the E_1/2, and can be useful in predicting the E_1/2 of other compounds.      

Highly thermal stable transparent conducting SnO2:Sb epitaxial films prepared on α-Al2O3 (0 0 0 1) by MOCVD

Antimony-doped tin oxide (SnO₂:Sb) single crystalline films have been prepared on α-Al₂O₃ (0 0 0 1) substrates by metal organic chemical vapor deposition (MOCVD). The antimony doping was varied from 2% to 7% (atomic ratio). Post-deposition annealing of the SnO₂:Sb films was carried out at 700-1100 °C for 30 min in atmosphere ambient. The effect of annealing on the structural, electrical and optical properties of the films was investigated in detail. All the SnO₂:Sb films had good thermal stability under 900 °C, and the 5% Sb-doped SnO₂ film exhibited the best opto-electrical properties. Annealed above 900 °C, the 7% Sb-doped SnO₂ film still kept high thermal stability and showed good electrical and optical properties even at 1100 °C.     

Novel polybenzimidazole/graphitic carbon nitride nanosheets composite membrane for the application of acid-alkaline amphoteric water electrolysis

It is a great challenge to develop membrane materials with high performance and long durability for acidalkaline amphoteric water electrolysis.Hence,the graphitic carbon nitride(g-C₃N₄)nanosheets were compounded with the(2,2'-m-phenylene)-5,5'-benzimidazole(m-PBI)matrix for the preparation of m-PBI/g-C₃N₄ composite membranes.The synthesis of g-C₃N₄ nanosheets and m-PBI matrix have been confirmed by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscoy(TEM)and ¹H nuclear magnetic resonance spectra(¹H NMR),respectively.The fourier transform infrared spectroscopy(FT-IR)and SEM of the composite membranes showed the g-C₃N₄ nanosheets were well dispersed in the m-PBI/g-C₃N₄ composite membrane.The mechanical properties test exhibited the good mechanical strength,and the TGA curves of m-PBI showed the high thermal stability of composite membranes.Besides,the m-PBI/g-C₃N₄ composite membrane showed excellent proton and hydroxide ion conductivity,which was higher than pure m-PBI and Nafion 115 membrane.The acid-alkaline amphoteric water electrolysis test showed m-PBI/1%g-C₃N₄ composite membrane has the best performance with a current density of 800 mA cm^-2 at cell voltage of 1.98 V at 20℃.It showed that m-PBI/g-C₃N₄ composite membrane has a good application prospect for acid-alkaline amphoteric water electrolysis.     

Well-posedness and exponential stability of a flexible structure with second sound and time delay

In this paper, we consider a non-uniform flexible structure with time delay under Cattaneo's law of heat condition. We prove that the system is well-posed, and the system is exponential decay under a small condition on time delay.     

A comparison of the diastereoisomers, silybin A and silybin B, on the induction of apoptosis in K562 cells

Two diastereoisomers of silybin, silybin A and silybin B, were separated from silymarin by HPLC in our previous study. The present study assessed the effects of the diastereoisomers on cell apoptosis, and compared these with their mixture, silybin, in human chronic myeloid leukemia K562 cells. Both isomers showed stronger effects on cell growth inhibition and apoptosis induction than silybin. Compared with silybin B, silybin A showed higher effects on the production of intracellular reactive oxygen species and Ca2+. These results suggest that silybin A and silybin B have similar potency on apoptosis induction with different oxidative effects. Antagonistic effects may exist between silybin A and silybin B, partially through ROS production and Ca2+ increase.     

Sign-changing solutions of a class of nonlocal quasilinear elliptic boundary value problems

This paper is concerned with nonlocal Kirchhoff?s equation

     

A Novel 3D Cobalt（II） Complex Constructed by 2,2＇-（1,4-Butanediyl）bis（1H-benzimidazole） Ligand

A novel 3D polymer 1 (C26H22CoN4O4, Mr = 513.41) constructed from H2C4BIm (2,2'-(1,4-butanediyl)bis(1H-benzimidazole)], 1,3-bdc (1,3-benzenedicarboxylate) and Co(II) has been successfully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analysis. The crystal belongs to the tetragonal system, space group I-42d with a = 24.315(5), b = 24.315(5), c = 8.343(2), V = 4933(2)3, Z = 8, Dc = 1.383 g/cm3, μ(MoKα) = 0.735 mm-1, F(000) = 2120, S = 1.156, the final R = 0.0596 and wR = 0.1346 for 1529 reflections with I > 2σ(I). Complex 1 contains 1D chains which are connected by extensive hydrogen-bonding interactions to form the 2D folded layer and 3D framework, which also stabilize the structure.     

Synthesis of large surface area nano-sized BiVO4 by an EDTA-modified hydrothermal process and its enhanced visible photocatalytic activity

In this work, monoclinic scheelite-type BiVO₄ nanoparticle with large surface area has been successfully synthesized, using Bi(NO₃)₃ and NH₄VO₃ as raw materials, through a hydrothermal process in the presence of ethylene diamine tetraacetic acid (EDTA). It is demonstrated that the nanoparticle size of as-prepared BiVO₄ becomes small by decreasing hydrothermal temperature, shortening hydrothermal reaction time and increasing EDTA amount used. The resulting BiVO₄ nanoparticle with large surface area exhibits a good photocatalytic performance for degrading phenol solution as a model organic pollutant under visible illumination. The key of this method is the chelating role of EDTA group in the synthetic process that it can greatly control the concentration of Bi³⁺, leading to the growth inhibition of BiVO₄ crystallite. The work provides a route for the synthesis of Bi-containing nano-sized composite oxides with large surface area.     

Structural and optical properties of Ga2O3:In films deposited on MgO (1 0 0) substrates by MOCVD

Ga₂O₃:In films with different indium (In) content x [x=In/(Ga+In) atomic ratio] have been deposited on MgO (1 0 0) substrates by metalorganic chemical vapor deposition (MOCVD). Structural analyses revealed that the film deposited with actual In content (x′) of 0.09 was an epitaxial film and the films with x′=0.18 and 0.37 had mixed-phase structures of monoclinic Ga₂O₃ and bixbyite In₂O₃. The absolute average transmittance of the obtained films in the visible region exceeded 95%, and the band gap was in the range of 4.74-4.87 eV. Photoluminescence (PL) measurements were performed at room temperature, in which the visible luminescences were strong and could be seen by the naked eye. The strong emissions in the visible light region were proposed to originate from the gallium vacancies, oxygen deficiencies and other defects in these films.