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Nanocomposite particles SrFe12O19/ CoFe2O4 were synthesized by sol-gel method. The nanocomposites are formed at the calcining temperature around 850 oC in 5 hours. The phase composition, surface morphology and magnetic properties of the nanocomposites were investigated using XRD, SEM and VSM, respectively. The results show that the magnetic properties of nanocomposite particles are strongly influenced by the molar ratios of the hard and soft phases and particle size distributions. The samples with the mass ratio of Rm= SrFe12O19/ NiFe2O4 = 1/3 and 1/5 are characterized with a “bee waist” type hysteresis loop. While all the samples RV show an excellent smooth hysteresis loop and a single – phase magnetization behavior. The coercivity decreases significantly and the magnetization drastically increases with decreasing of volume ratio RV. Keywords: nanocomposite, sol- gel method, exchange coupling. 

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Numerous countries have shown signs of environmental pollution to prioritize economic growth and benefits, leading to seriously contaminated waters. This work indicated the method to synthesize a green material, which could remove contaminants to protect the natural environment. The porosity and functionality effects of amine-functionalized activated carbon (AFAC) enhanced the removal of toxic heavy metals (THMs) in aqueous solution. The raw activated carbon (RAC) was thermally modified with ultrahigh pure nitrogen (UHPN) at 500°C and 1000°C and then amine-functionalized with coupling agent of aminopropyltriethoxysilane (APS). They were denoted as AFAC-5 and AFAC-10, respectively. The data showed an enhanced metal adsorption capacity of the AFACs, because the modification produced more desired porosity and increased amine functional groups. AFAC-10, modified at a higher temperature, showed much higher THM adsorption capacity than AFAC-5, modified at a lower temperature, and RAC. The adsorption capacity decreased in the following order: Ni > Cd > Zn, which was in good agreement with the increasing electronegativity and ionic potential and the decreasing atomic radius. The maximum THM adsorption capacity of AFAC-10 for Ni, Cd, and Zn was 242.5, 226.9, and 204.3 mg/g, respectively.

Recently, teaching - learning Science subjects in English has become an urgent need of Vietnamese Education. Although piloted in high schools for gifted students and high-qualified schools with experienced teachers and good students, teaching Science subjects in English still faces many obstacles for many reasons. Among them, finding an appropriate teaching method may be the biggest challenge. The students who are good at Science subjects often does not feel confident about English. Whilst, those who are proficient in foreign language are usually afraid of science subjects and have not yet built up speciallized vocabulary about science. In this context, teaching Science subjects using Content and Language Integrated Learning (CLIL) approach shows high application potential due to the ability to balance both factors - Science knowledge and English simultaneously in a lesson. This study introduces the characteristics of CLIL approach and proposes the steps for preparing CLIL lesson plan. Also included is the analysis of the results of the Pedagogical experiment in High school of Education and Science.

This study is aimed at exploring the effects of SiO2 nanoparticles on the crosslinking and mechanical and thermal properties of UV curing acrylic epoxy coating. The curing polymerization process and thermal and mechanical properties of UV-curable acrylate epoxy system have been evaluated with or without the presence of SiO2 nanoparticles. To fabricate the UV curing acrylic epoxy/SiO2 nanocomposite coating, nano-SiO2 particles (0.5–5 wt.% by weight of resin) were added in the photo-curable system using sonication for 3 h. Various techniques for characterization have been used, such as FESEM (field emission scanning electron microscope), FTIR (Fourier-transform infrared spectroscopy), TGA (thermogravimetry analysis), gel fraction, and swelling degree analyses. FESEM data indicated that at the content of 2.5 wt.%, nanosilica was homogeneously dispersed in the coating procedure. However, once added 5 wt.%, large aggregation portions were found inside the coating matrices. Surprisingly, nano-SiO2 could play dual roles, as both UV absorbers and nanoreinforcers, in this nanocomposite coating. Besides, data from FTIR, gel fraction, and swelling degree analyses confirmed the role of SiO2 nanoparticles as UV absorbers that reduced the conversion performance of acrylate double bonds, thus increased slightly the swelling degree of coating. In addition, incorporation of SiO2 nanoparticles (as nanofillers, at content of 2.5 wt.%) in the polymer matrix enhanced significantly the abrasion resistance and thermal stability of the coating, by 60% (from 98.3 to 158.4 lite/mil) and 9°C (from 348°C to 357°C), respectively.