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Graphite is a versatile material used in various fields, particularly in the power source manufacturing industry. Nowadays, graphite holds a unique position in materials for anode electrodes in lithium-ion batteries. With a carbon content of over 99% being a requirement for graphite to serve as an electrode material, the graphite refinement process plays a pivotal role in the research and development of anode materials for lithium-ion batteries. This study used three different processes to purify spherical graphite through wet chemical methods. The spherical graphite after the purification processes was analysed for carbon content by using energy-dispersive X-ray (EDX) spectroscopy and was evaluated for structural and morphological characteristics through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analyses. The analyses results indicate that the three-step process via H2SO4–NaOH–HCl cleaning can elevate the carbon content from 90% to above 99.9% while still maintaining the graphite structure and spherical morphology, thus enhancing the surface area of the material for anode application. Furthermore, the spherical graphite was studied for electrochemical properties when used as an anode for Li-ion batteries using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) measurements. The results demonstrated that the purification process significantly improves the material's capacity with a specific capacity of 350 mAh/g compared to the 280 mAh/g capacity of the anode made of spherical graphite without purification. [ABSTRACT FROM AUTHOR]

Ho Chi Minh City has many favorable conditions for foreign invested enterprises (FDI) to invest. Labor relations in the foreign-invested sector at enterprises in Ho Chi Minh City is a necessary and urgent issue with the great significance in terms of both theory and practice, as a primary concern of employers and employees. Good handling of this relationship is also one of the important factors to attract foreign direct investment and enterprises in Ho Chi Minh City, so as to contribute to economic growth in the process of industrialization, modernization, increase budget revenue, increase export turnover, partly solving labor problems and economic restructure in the trend of global economic integration at the locality. However; besides the achieved results, the labor relations situation in enterprises still has many shortcomings, such as: reforming policies to attract foreign direct investment is still limited, the state management still has many shortcomings, not paying enough attention to the policy of encouraging employees, etc. Therefore, it is necessary to propose solutions to improve labor relations, enhancing the lives of workers in non-state enterprises, partly making healthy labor relations in foreign-invested enterprises in Ho Chi Minh City. [ABSTRACT FROM AUTHOR]

Green synthesis has emerged as a sustainable approach for the fabrication of nanomaterials in the last few decades. Leaf extracts have been considered low-cost and highly efficient reactants for the synthesis of nanoparticles. In this study, an aqueous extract of Cleistocalyx operculatus leaves was employed as a reductant to synthesize Ag/TiO 2 nanocomposites. The morphology, structure, and interface interaction of the Ag/TiO 2 nanocomposites were investigated by (i) X-ray diffraction (XRD) to determine the crystallinity, (ii) scanning electron microscopy (SEM) to determine the morphologies, (iii) energy dispersive X-ray spectroscopy (EDX) to determine the elemental composition and distribution, and (iv) diffuse reflectance spectroscopy (DRS) to understand the optical properties. The results showed that Ag nanoparticles (AgNPs) with particle sizes of 20-40 nm homogeneously covered the surface of the TiO 2 nanoparticles. The green-synthesized Ag/TiO 2 nanocomposite also exhibited an excellent photodegradation ability for Rhodamine B with a removal percentage up to 91.4% after 180 min of photocatalytic reaction., (Copyright © 2022 Elsevier Ltd. All rights reserved.)