英语翻译Physicochemical characterization of nanosize zinc oxide

英语翻译
Physicochemical characterization of nanosize zinc oxide and titanium dioxide used as UVR sunscreen agents in cosmetic formulations
Abstract:The physical (particulate) sunscreen agents ZnO and TiO2,are increasingly used to provide UV protection in a wide variety of cosmetic and personal care products.The particle size distribution (PSD) of each oxide directly impacts product performance in two critical ways.First is the UV attenuation efficiency.Second,cosmetically acceptable and aesthetically pleasing products must also be transparent (non-whitening) when applied to the skin.The actual PSD in the final sunscreen formulation is very dependent upon the method of preparation and especially the quality of the oxide dispersion in the particular cosmetic vehicle.ZnO and TiO2 have their own chemical compatibility that must be recognized to obtain maximum performance.This requires a detailed knowledge of the particulate surface chemistry and how that relates to the other (chemical) components in the product.For example,the majority of titanias currently used in cosmetic applications have been surface modified.This results in a very wide,variation of surface chemistry that critically affects dispersibility,especially when formulating mixed oxide systems.All these factors will be reviewed and illustrated.