Interaction properties of double-hump solitons in the dispersion decreasing fiber

Nonlinear Dynamics - In this paper, the high-order coupled variable coefficient nonlinear Schrödinger equations is studied. The double-hump soliton solutions for the equations are obtained...     

Global well‐posedness of 2D nonlinear Boussinesq equations with mixed partial viscosity and thermal diffusivity

In this paper, we discuss with the global well‐posedness of 2D anisotropic nonlinear Boussinesq equations with any two positive viscosities and one positive thermal diffusivity. More precisely, for three kinds of viscous combinations, we obtain the global well‐posedness without any assumption on the solution. For other three difficult cases, under the minimal regularity assumption, we also derive the unique global solution. To the authors' knowledge, our result is new even for the simplified model, that is, F(θ) = θe₂. Copyright © 2017 John Wiley & Sons, Ltd.     

人工纳米材料与植物的相互作用:植物毒性、吸收和传输

近十几年来纳米科技取得了突飞猛进的发展,人工纳米材料的应用日益广泛,势必导致大量纳米材料进入生态环境中,因此纳米材料可能带来的环境污染和生态效应也受到了高度关注。越来越多的研究表明,纳米材料对微生物、水生和陆生动物和植物都具有一定的毒性效应。植物是生态系统的重要组成部分,一方面纳米材料可能影响植物的发育与生长;另一方面,植物的代谢活动会影响纳米材料在环境中的迁移转化行为及其在食物网中的传递。但是,目前关于纳米材料与植物相互作用的研究还十分匮乏,多数研究只局限于相互作用导致的表观现象,例如:毒性的研究多关注于纳米材料对植物或植物细胞的表观毒性效应,缺乏对致毒机制的探讨;纳米材料的植物吸收和传输研究也仅停留在现象观察阶段,缺乏对吸收与传输机理的深入研究。而且很多研究结论还存在较大的争议,因此非常有必要对相关的研究进展与结论做全面梳理。本文综述了近年来关于纳米材料与植物相互作用的研究,从植株到植物细胞水平讨论了不同纳米材料对植物的毒性效应以及纳米材料的植物吸收和传输过程。     

Asymmetric double-layer composite electrolyte with enhanced ionic conductivity and interface stability for all-solid-state lithium metal batteries

All-solid-state Li metal battery has been regarded as a promising battery technology due to its high energy density based on the high capacity of lithium metal anode and high safety based on the all solid state electrolyte without inflammable solvent.However,challenges still exist mainly in the poor contact and unstable interface between electrolyte and electrodes.Herein,we demonstrate an asymmetric design of the composite polymer electrolyte with two different layers to overcome the interface issues at both the cathode and the anode side simultaneously.At the cathode side,the polypropylene carbonate layer has enough viscosity and flexibility to reduce the inter-facial resistance,while at the Li anode side,the polyethylene oxide layer modified with hexagonal boron nitride has high mechanical strength to suppress the Li dendrite growth.Owing to the synergetic effect between different components,the asprepared double layer composite polymer electrolyte demonstrates a large electrochemical window of5.17 V,a high ionic conductivity of 6.1×10~(-4) S/cm,and a transfe rence number of 0.56,featuring excellent ion transport kinetics and good chemical stability.All-solid-state Li metal battery assembled with LiFePO_4 cathode and Li anode delivers a high capacity of 150.9 mAh/g at 25℃ and 0.1 C-rate,showing great potential for practical applications.     

Facile Synthesis of Polysubstituted Cyclopropanes in a Two-Phase Solid-Liquid System

The Michael addition of α-chloro esters to α,β-unsaturated systems was catalyzed by phase transfer catalyst, and the some polysubstituted cyclopropanes were facilly synthesized.     

A NECESSARY AND SUFFICIENT CONDITION FOR THEOSCILLATION OF SOLUTIONS OF LIENARD TYPE SYSTEM WITH MULTIPLE SINGULAR POINTS

I.IntroductionJ.R.Graer']andG.VillariI2]gavenecessar\JandsufficientconditionsfortheoscillationofsolutionofLienardsystemf~])~F(x),y~~glXJ(l.l)HanMaoanI3]gaveoscillatirytheoremsforLienardt}'pesystemt'.ithasingularpointi~h(.t/)~F(x),#~~g(x)(1.2)Whereas,aloto…     

All-silicon chiral metasurfaces and wavefront shaping assisted by interference

The usage of full-color imaging in digital pathology produces significant results. Compared with a grayscale image or a pseudocolor image containing contrast information, a full-color image can identify and detect the target object better with color texture information. Fourier ptychographic microscopy(FPM) is a high-throughput computational imaging technique that breaks the tradeoff between high resolution(HR) and a large field of view. It also eliminates the artifacts of scanning and stitching in digital pathology and improves its imaging efficiency. However, the conventional full-color digital pathology based on FPM is still time-consuming because of the repeated experiments with tri-wavelengths. A color transfer FPM approach termed "CFPM" was reported. The color texture information of a low-resolution full-color pathologic image is directly transferred to the HR grayscale FPM image captured by only a single wavelength. Both of the color space of FPM based on the standard CIE-XYZ color model and the display based on the standard RGB color space were established. Different FPM colorization schemes were analyzed and compared with 30 biological samples. Three types of evaluation approaches were provided, including the root-mean-square error(RMSE), the difference maps, and the image histogram cosine similarity. The average RMSE values of the conventional method and CFPM compared with the ground truth were 5.3% and 5.7%, respectively. Therefore, the reconstruction time is significantly reduced by 2/3 with the sacrifice of precision of only 0.4%. The CFPM method is also compatible with advanced fast FPM approaches to further reduce computation time.     

Adsorption of uranium from aqueous solution by graphene oxide nanosheets supported on sepiolite

Adsorptive behavior of uranium from aqueous solution on graphene oxide supported on sepiolite composites (GO@sepiolite composites) as a function of pH, ionic strength, temperature and initial uranium concentration was carried out by the batch techniques. GO@sepiolite composites was synthesized and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and potentiometric acid–base titration. According to XRD patterns and SEM images, the graphene oxide nanosheets were grafted on sepiolite surface successfully. The macroscopic results showed that the adsorption of uranium on GO@sepiolite composites was significantly depended on pH, whereas no effect of ionic strength on uranium adsorption at high pH and high ionic strength conditions was observed. The uptake equilibrium is best described by Langmuir adsorption isotherm, and the maximum adsorption capacity (Q_e) of GO@sepiolite composites at pH 5.0 and T = 298 K were calculated to be 161.29 mg/g. Thermodynamic results indicated that the adsorption of uranium on GO@sepiolite composites is the spontaneous and exothermic process.     

Controllability and observability for a class of time-varying impulsive systems

This paper is concerned with the controllability and observability for a class of piecewise linear time-varying impulsive systems. Several sufficient and necessary conditions for state controllability and observability of such systems are established. Meanwhile, corresponding criteria for time-invariant impulsive systems are also obtained and the criteria are compared with the existing results.