In this research, structural, magnetic properties and photocatalytic activity of cobalt ferrite spinel (CoFe2O4) nanoparticles were studied. The samples were characterized by X-ray powder diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM), transmission electronic microscopy (TEM), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectroscopy (FTIR), and UV-visible diffused reflectance spectroscopy (DRS) analysis. The XRD analysis revealed the formation of the single-phase CoFe2O4 with a cubic structure that is annealed at 500–700 °C in 3 h. The optical band gap energy for CoFe2O4 was determined to be in the range of 1.57–2.03 eV. The effect on the magnetic properties of cobalt ferrites was analyzed by using a vibrating sample magnetometer (VSM). The particle size and the saturation magnetization of cobalt ferrite nanoparticles increased with increasing annealing temperature. The photocatalytic activity of CoFe2O4 nanoparticles was investigated by using rhodamine B dye under visible light. The decomposition of rhodamine B reached 90.6% after 270 min lighting with the presence of H2O2 and CF500 sample.

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There are many factors affecting the quality of faculty that numerous researchers mentioned, analyzed and pointed out the different degrees of influence. The paper studies external factors affecting the quality of faculty such as Political regime, Management mechanism and Salary regime. These three factors have been existing in each country and make a different impact on the quality of faculty creating the unique characteristics of each country. The author builds a theoretical framework for research on the above-mentioned three ones and conduct a direct survey of 400 lecturers from 10 universities in Hanoi -the capital city of Vietnam. The survey is selectively done, in which its surveyed subjects are lecturers with doctorate or higher and their working time from 5 years or more. Through secondary data collected from published documents combined with those gained from direct investigations and surveys, the author contributes to clarifying the impact of the abovementioned factors on the quality of Vietnamese faculty. From that result, he proposes a number of workable solutions on the policies with the hope of providing leaders and managers with scientific arguments so that they have more sound bases to appropriately adjust their policies to satisfy the essential needs of lecturers, which helps them have more opportunities to create and maximize their capacity. That also contributes to completing the policies on developing a team of high-quality Vietnamese faculty meeting the requirements of higher education in the modern and integrated social context.