Papers by Author: Dong Bin Zhu

Abstract: A novel ceramic forming process, dual-phase materials extrusion process based on solid freeform fabrication (also known as rapid prototyping), has been developed. It is a kind of selective slurry extrusion (SSE) technique previously proposed in our group. The dual-phase materials extrusion machine was constructed with micro-extrusion system and 3-axial positioning system. To demonstrate the usability of this machine, a functionalized dental crown was directly fabricated with support material and dental material from 3D model (STL format) of a human tooth. The fabrication time is usually in 20-50 min.

Abstract: Thirty-eight isolates of Escherichia coli (E.coli) were isolated from chickens either ill or dead suspected with E.coli. These chickens come from chicken breeding farms in the districts of Baoding, Qinhuangdao and Beijing of China. The results of the antibiotics sensitivity test in the thirty-eight isolates to twenty-four kinds of antibiotics show that all isolates have presented antibiotic resistance disparately as well as multiresistance. All isolates are sensitive to Cephalosporins antibiotics and Aminoglycosides antibiotics such as Amikacin, Cefazolin, Cefradine, Cefoperazone and Ceftriaxone. Thirty-eight isolates are extremely resistant to Penicillins antibiotics, Lincomycins antibiotics, Tetracyclines antibiotics and Macrolides antibiotics such as Midecamycine, Lincomycin, Carbenicillin, Tetracycline, Amoxicillin. Antibiotics sensitivity test provides a guidance for antibiotic application and scientific research on poultry farms.

Abstract: The graded composite materials were fabricated by direct inkjet printing of nano-electropolar mineral and nano-hydroxyapatite powders for the study of inhibiting function on streptococcus mutans, which is a primary pathogen for human dental caries. The electropolar mineral can be utilized in many fields due to its spontaneous permanent polarity and far infrared emission properties. In this study, the graded distribution of the streptococcus mutans on the surface of graded composite materials was investigated by energy dispersion spectrometry, and the mechanism of which is that the streptococcus mutans was remained in the culture of pH at about 8.5 self-adjustment induced by the electropolar mineral. This culture inhibits growth and acid production of streptococcus mutans. Therefore, this composite materials have inhibitory effects on streptococcus mutans, and can be used as a promising biomaterial for preventing human teeth from caries.

Abstract: An Ag-Ce-TiO2 composite film was prepared by incorporating Ag in the Ce-TiO2 films with an impregnation method through photoreduction. The bactericidal activity of the Ag-Ce-TiO2 composite film and the effect of deposition of silver and doping cerium in the different irradiations on the antibacterial performance were assessed against Escherichia coli (E. coli). TIhrough characterization of X-ray diffraction (XRD), X-ray photoelectronic spectra (XPS) and UV/VIS diffusive reflectance spectra (DRS), it was found that the Ag-Ce-TiO2 composite film was composed of predominant anatase titania, cerium oxides (in the form of Ce2O3/CeO2) and silver nanoparticles. Moreover, the bactericidal activity of the Ag-Ce-TiO2 composite film and the effect of deposition of silver and doping cerium in the different irradiations on the antibacterial performance were assessed against Escherichia coli (E. coli). The results show that the Ag-Ce-TiO2 composite film has much higher antibacterial efficiency than that of glass and pure TiO2 film either in the room light or in the dark. Therefore, this composite film is promising in applications of antimicrobial and self-clean technologies.