This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap.In this approach,instead of generating mesh for the gap,a contact boundar...This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap.In this approach,instead of generating mesh for the gap,a contact boundary is introduced in the finite element modeling to obtain a reasonable field distribution;then the field in the gap is approximated based on the continuity condition at their interface,so that the adhesion force can be properly calculated.Moreover,a simple equivalent circuit model is introduced to explain how the thin gap influences the adhesion force significantly.Numerical experiments are given to demonstrate the validity of the proposed method and the significance of the thin gap.展开更多
Derived from dry powder coating of metals, electrostatic powder coating for pharmaceuticals is a technology for coating drug solid dosage forms. In this technology, coating powders, containing coating polymers, pigmen...Derived from dry powder coating of metals, electrostatic powder coating for pharmaceuticals is a technology for coating drug solid dosage forms. In this technology, coating powders, containing coating polymers, pigments, and other excipients, are directly sprayed onto the surface of the solid dosage forms through an electrostatic gun without using any organic solvent or water. The deposited coating powders are further cured to form a coating film. Electrostatic powder coating technology has many advantages compared to other pharmaceutical coating methods. It can eliminate the limitations caused by the organic solvent in solvent coating such as environmental issues and health problems. And electrostatic powder coating technology also surpasses aqueous coating due to its shorter processing time and less energy consumption, leading to a lower overall cost. Furthermore, the utilization of electrical attraction can promote the movement of coating powders towards the substrate, leading to an enhanced coating powder adhesion and coating efficiency, which make it more promising compared to other dry coating technologies. The objective of this review is to summarize the coating principles, apparatus, and formulations of different electrostatic powder coating technologies, giving their advantages and limitations and also analyzing the future application in the industry for each technology展开更多
基金National Natural Science Foundation of China(No.11272074)National Science and Technology Major Project(No.2011ZX02403-00)。
文摘This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap.In this approach,instead of generating mesh for the gap,a contact boundary is introduced in the finite element modeling to obtain a reasonable field distribution;then the field in the gap is approximated based on the continuity condition at their interface,so that the adhesion force can be properly calculated.Moreover,a simple equivalent circuit model is introduced to explain how the thin gap influences the adhesion force significantly.Numerical experiments are given to demonstrate the validity of the proposed method and the significance of the thin gap.
文摘Derived from dry powder coating of metals, electrostatic powder coating for pharmaceuticals is a technology for coating drug solid dosage forms. In this technology, coating powders, containing coating polymers, pigments, and other excipients, are directly sprayed onto the surface of the solid dosage forms through an electrostatic gun without using any organic solvent or water. The deposited coating powders are further cured to form a coating film. Electrostatic powder coating technology has many advantages compared to other pharmaceutical coating methods. It can eliminate the limitations caused by the organic solvent in solvent coating such as environmental issues and health problems. And electrostatic powder coating technology also surpasses aqueous coating due to its shorter processing time and less energy consumption, leading to a lower overall cost. Furthermore, the utilization of electrical attraction can promote the movement of coating powders towards the substrate, leading to an enhanced coating powder adhesion and coating efficiency, which make it more promising compared to other dry coating technologies. The objective of this review is to summarize the coating principles, apparatus, and formulations of different electrostatic powder coating technologies, giving their advantages and limitations and also analyzing the future application in the industry for each technology
