This paper is devoted to the determination of the dispersive component of the surface energy of two boron materials such as h-BN and BPO4 surfaces by using the inverse gas chromatography (IGC) at infinite dilution. The specific interactions and Lewis’s acid-base parameters of these materials were calculated on the light of the new thermal model concerning the dependency of the surface area of organic molecules on the temperature, and by using also the classical methods of the inverse gas chromatography as well as the different molecular models such as Van der Waals, Redlich-Kwong, Kiselev, geometric, Gray, spherical, cylindrical and Hamieh models. It was proved that h-BN surface exhibits higher dispersive surface energy than BPO4 material.
The specific properties of interaction of the two boron materials were determined. The results obtained by using the new thermal model taking into account the effect of the temperature on the surface area of molecules, proved that the classical IGC methods, gave inaccurate values of the specific parameters and Lewis’s acid base constants of the solid surfaces. The use of the thermal model allowed to conclude that h-BN surface has a Lewis basicity twice stronger than its acidity, whereas, BPO4 surface presents an amphoteric character.
In the new era, the Yiban platform has become an important carrier for college counselors to carry out online ideological and political education for college students. Utilizing the Yiban platform to improve the effectiveness of online ideological and political education is a practical need for ideological and political education in universities, but there is a deviation between its actual construction and the expected effect. At present, college counselors face difficulties in carrying out online ideological and political education based on the Yi Ban platform, such as a lack of online thinking, insufficient new media literacy, and weak content innovation. Based on the fundamental task of cultivating morality and talents, starting from the job responsibilities of counselors, fully utilizing the platform of changing classes, and striving in four directions: improving political literacy and theoretical level, building a composite talent team, valuing the role of "opinion leaders", and adhering to the "content as the king" orientation, can provide a feasible path for comprehensively improving the quality of online ideological and political education for college students.
In this study, the effect of porogenic solvents on pore size distribution of the polycaprolactone (PCL) thin films was investigated. Five thin PCL films were prepared using the solvent-casting method. Chloroform, Methylene Chloride (MC) and three different compositions of MC/ Dimethylformamide (DMF) (80/20, 50/50 and 20/80) were used as solvents. Scanning Electron Microscopy (SEM) investigations were employed to study morphology and consequently the pore size distribution of the prepared films. The PCL films made by chloroform and MC as a solvent were completely non-porous. Whereas the other films (made by a combination of MC and DMF) showed both uni-modal and bi-modal pore size distributions.
Heavy metal contaminated soil due to industrial, agricultural and municipal activities is becoming a global concern. Heavy metals severely affect plants, animals and human health. A suitable technology is necessary for heavy metals removal because it cannot self-decomposition as organic compounds. Among the various technologies surveyed, phytoremediation is one of the safest, most innovative, environmental friendly and cost-effective approach for heavy metals removal. Nevertheless, traditional phytoremediation practices pose some limitations such as long processing time, unstable treatment efficiency and limited application at large scale. In many methods proposed to improve phytoremediation, integrated phytoremediation has been studied in the recent years. Integrated phytoremediation use chelating agents and phytohormones to enhance phytoremediation. This is an environmentally safe, saving time and relative high effective method. Results showed that the association of a metal ion and a chelating agent to form chelates helps to maintain the availability of metals in the soil for the uptake of plants. Phytohormones supply nutrients for the soil to support vegetable growth. Therefore, integrated phytoremediation is a promising solution to overcome the disadvantages of conventional phytoremediation. It should be taken commercialization and need more applied projects in this field to demonstrate and clarify the real potential of this technology. In view of above, this manuscript reviews the mechanism and the efficiency of integrated phytoremediation for heavy metals in contaminated soil to give an overview of this technology.
This study aimed to evaluate the influence of various factors on the corporate governance of state-owned enterprises with 100% capital ownership in Vietnam. Employing quantitative research methods, the article conducted an analysis of 250 survey samples taken from such enterprises and utilized regression analysis techniques. The findings revealed eight factors that significantly impact the corporate governance of these entities in Vietnam: enterprise awareness, ownership model, the state’s role as an owner, integration, board of members, legal framework, managerial experience, and activity objectives. Leveraging these research outcomes, several recommendations have been proposed to enhance the corporate governance practices within state-owned enterprises holding complete capital ownership in Vietnam.
In the teaching of graphic design, students' learning state and learning effect are poor due to the lack of attractiveness of teaching materials. In order to fully display the graphic design knowledge contained in totem patterns, a model based on the pattern elements of totem patterns was constructed. Through Marvelous Designer software, the display of totem visual effects under different pattern element configurations was realized, providing a basis for the comparative explanation of graphic design teaching. When designing the teaching content, based on the totem art culture, it has constructed three parts of teaching methods of plane composition, teaching contents of plane composition and teaching concepts of plane composition, which correspond to the material selection, composition and freehand brushwork skills of totem patterns in modeling creativity and expression techniques, and the range of material selection, composition form and connotation of plane design teaching, the specific application is realized through knowledge transfer.
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