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The article concentrates on the educational features of modern everyday communication. The materials used were texts of notices that prove the existence of a crisis in modern mass communication. The reasons of crisis phenomena in speech practice have been established and ways out of the situation have been suggested.

Structural color materials based on periodic micro and nano structures present unique color rendering mechanism and optical properties, and have a wide range of applications in display, packaging, sensing and other fields. However, it is still facing the problems of constructing large area, good consistency and low cost periodic structures. In this paper, the structural color film was prepared by annealing treatment on a periodic template. The effects of coating time, annealing time and annealing process on the optical properties of the sample such as hue and saturation were analyzed. It was confirmed that the sample with 300 nm polystyrene microsphere template presented orange yellow with incident angle of 30° before annealing, then turned to be light pink under 800 °C for 120 min annealing process and orange red under 800 °C for 180 min in air. Additionally, the sample with 420 nm polystyrene microsphere template showed cyan before annealing, and yellow-green under 800 °C for 120 min annealing treatment and orange-yellow under 800 °C for 180 min. The periodicity of the annealed gold microspheres was still limited by the template period with different diameters. Morever, when the coating and annealing time were the same, the higher the annealing temperature was, the higher the saturation get. Under the same coating time and annealing temperature, the saturation was higher with short annealing time, and the hue blue-shifted as the incident angle increased from 15° to 45°. While fixing the annealing time and temperature, the saturation increased gradually as the coating time increasing from 10S to 40S, and the color of the sample red-shifted. [ABSTRACT FROM AUTHOR]

(E)-N2,N2-dimethyl-6-styryl-1,3,5-triazine-2,4-diamine and (E)-N-(4-(dimethylamino)-6-styryl-1,3,5-triazin-2-yl) acetamide are important intermediates for the synthesis of triazine compounds. The structure of the target compounds were confirmed using 1H NMR, 13C NMR, HRMS and FT-IR spectroscopy. The precise structure of (E)-N2,N2-dimethyl-6-styryl-1,3,5-triazine-2,4-diamine and (E)-N-(4-(dimethylamino)-6-styryl-1,3,5-triazin-2-yl) acetamide were analyzed using single-crystal X-ray diffraction. The molecular structures were further calculated using density functional theory (DFT), which were compared with the X-ray diffraction value. The results of the conformational analysis indicate that the molecular structures optimized by DFT were consistent with the crystal structures determined by single crystal X-ray diffraction. In addition, the molecular electrostatic potential and frontier molecular orbitals of the title compounds were further investigated by DFT, and some physicochemical properties of the compounds are revealed. [ABSTRACT FROM AUTHOR]

According to these drawbacks of traditional direct power control(DPC) in single-phase PWM rectifiers such as slow dynamic response,poor anti-interference ability and variable switching frequency, an algorithm based on outer loop adopting the feedback of capacitor energy storage and internal loop with deadbeat predictive direct power control is further given.This algorithm improves the speed of dynamic response and the ability of anti-interference with the outer loop control method based on the feedback variable of capacitor energy storage and load power feed forward. Meanwhile,the auto-regressive algorithm simplifies the controller design, and addresses the issue of delay compensation in traditional control. Combined with the space vector modulation(SVPWM) the system′s switch frequency is fixed. Furthermore, it reduces the design costs without voltage′s phase detector. Finally, the proposed control method and traditional DPC method were compared in computer simulation respectively , and the simulation result verified the validity of the proposed control method.

In this paper, a kind of Fe3O4 magnetic nano material modified by fulvic acid (FA) was prepared and used for removing methylene blue in wastewater. The structure and morphology of the material were characterized by FT‐IR, PXRD, BET, XPS, VSM, SEM and TEM. The results showed that FA successfully coated on the surface of Fe3O4 magnetic nano particles. The newly prepared magnetic material had large specific surface area and porous structure. The specific surface area of the material was 92.15 m2/g. The average pore size of the material was 8.917 nm. Its saturation magnetization could reach to 55.74 emu/g. The magnetic responsiveness of the material was obvious. The magnetic material could be recovered by the magnet so it was easy to separate with the solution. The adsorption kinetic data fitted better with pseudo second order kinetic equation. The isothermal adsorption processes of the modified material to methylene blue had better linear correlation with Langmuir isothermal adsorption model. The thermodynamic parameter results indicated that the adsorption processes of the material to methylene blue were spontaneous exothermic processes. The results of the cyclic experiments indicated that the material had a certain value for reuse. [ABSTRACT FROM AUTHOR]