Understanding the piezocatalytic properties of the BaTiO(001) surface density functional theory.

Piezoelectric materials have been reported to possess catalytic activity under mechanical excitation, such as by ultrasonic waves or collisions. Energy band theory (EBT) is often used to explain the piezocatalytic phenomenon caused by the strain-induced charge separation, but the correlation between the piezoelectric polarization and catalytic activity has still not been fully understood in early theoretical studies with the EBT model. To reveal the intrinsic connection between the piezoelectric feature and surface catalytic activity, in this work, we employ first-principles Density Functional Theory (DFT) to investigate the prototype piezocatalyst BaTiO (001) surface (BTO).

Preparation and evaluation of novel bio-based Bis-GMA-free dental composites with low estrogenic activity.

Objective: Although bisphenol Aglycidyl methacrylate (Bis-GMA) are widely used in the dental composite, its raw materials include the petroleum-based product bisphenol A (BPA) with high estrogenic activity (EA). In this study, two new BPA-free dimethacrylate monomers from bio-based material creosol were synthesized and evaluated.

Methods: The renewable bisphenol monomer 5, 5'-methylenedicreosol (BCF) was prepared from bio-based material creosol.

[Pollution Characteristics and Risk Assessment of Tetracycline Antibiotics in Farmland Soil in Yinchuan].

A total of 43 surface soil samples were collected from Yinchuan farmland and high performance liquid chromatography(HPLC) was used to measure the concentrations of oxytetracycline(OTC), tetracycline(TC), chlortetracycline(CTC), and doxycycline(DOC). The pollution characteristics and spatial distribution of TC were further analyzed using spatial Kriging interpolation, and the ecological risks of OTC, TC, CTC, and DOC in farmland soils were also assessed. Tetracycline antibiotics were detected in all the soil samples at concentrations ranging from 40.

Construction and application of meteorological index for activity in nor-thern mountainous area of Sichuan Basin, China.

We analyzed the climate ecological suitability of in the northern mountain area of Sichuan Basin, based on the meteorological data of two meteorological stations, the production and the ecological characteristics and activity of . Taking temperature, moisture, light, wind and weather conditions as impact indices and referring to life meteorological index, we constructed a hierarchical calculation method for activity meteorological index and annual evaluation of in northern mountainous area of Sichuan Basin. Results showed that the main meteorological factors affecting activity in the study were temperature, relative humidity, sunshine hour, wind power and daytime cumulative duration of precipitation.

The incorporation of phosphorylated chitosan/amorphous calcium phosphate nanocomplex into an experimental composite resin.

This study evaluated the effect of incorporating phosphorylated chitosan/amorphous calcium phosphate nanocomplex (Pchi/ACP) into an experimental light-cure composite resin on mechanical-chemical properties and human dentin remineralization. The results showed that the mechanical strength and contact angles of the resins decreased with the increase incorporation of Pchi/ACP. Release concentrations of calcium in saline solution were measured at different time points, showing the incorporation of Pchi/ACP significantly increased calcium release within 14 days, and kept steady thereafter.

[Recent progress of robots in stomatology].

With the development of industrial robot technology, robotics has entered the medical field, and the research and development of new robots for many medical applications have become a significant research direction in global robotics. Robots are widely used in various aspects of dentistry, such as prosthodontics, orthodontics, implants, endodontics, and oral surgery. This article mainly introduces the application of robots in stomatology from the above five aspects.