The structure and crystallographic orientation of different layers (the cone layer, palisade layer and the crystal layer) in ostrich eggshells were studied by scanning electron microscope (SEM), X-ray diffraction (XRD) and transmission electron microscope (TEM) with selected area electron diffraction (SAED). It is found that the degree of 001 preferred orientation enhanced from inner to outer ostrich eggshells. A crystallographic orientation regulation was observed for the first time. The adjacent 1-5 calcite crystals with the same three-dimensional orientation are proposed to form a crystalline cluster with the size of several microns. The a-axes in the neighboring clusters orient from several degrees to tens of degrees.

Ion beam assisted deposition (IBAD) has been successfully used to produce a dense ultra-adherent and pinhole-free hydroxyapatite (HAp) layer on alumina substrates. After deposition the HAp-coated alumina was immersed in 20 ppm and 100 ppm AgNO3 solution to carry out the ion exchange between Ag1 and Ca21 in HAp. An obvious antimicrobial effect against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis was observed in the samples treated with 20 ppm AgNO3 solution. In contrast to this, the untreated samples did not show any bactericidal effect. Scanning electron microscopy (SEM) studies showed that Ag-rich phases were homogeneously distributed on the surface. X-ray diffraction (XRD) demonstrated that the surface structure in the samples without Ag was HAp, whereas with Ag it is HAp and AgCaP. The minimum inhibitory concentration of AgNO3 was measured to be 1.302 mg/ml. The release of Ag1 ions from the Ag-HAp

The antimicrobial ceramics (AC) based on hydroxyapatite (HA) were made in a wet chemical process with additions of AgNO3, Cu(NO3)2

A biomimetic calcium phosphate coating is expected to enhance the bioactivity and bone inductivity of human implants. This study presents a very simple, highly effective biomimetic method to obtain a calcium phosphate coating on a titanium substrate. Using NaH2PO4, a stable solution was prepared with high calcium and phosphate ion concentrations. This solution turned to a supersaturated calcification solution (SCS) when NaHCO3 was added. The addition of NaHCO3 elevated the pH value of the solution gradually and steadily. A uniform coating approximately 40 mm thick was found on the substrates after 24 h immersion. The compositions of the coatings were adjustable from hydroxyapatite (HA) to HAydicalcium phosphate dihydrate (DCPD). The calcium phosphate deposits were investigated by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transformed infrared (FT-IR) spectroscopy.

The structure and crystallographic orientation of mineral phase in the oblique prismatic layer of Mytilus edulisshell were studied by SEM, XRD and TEM with selected area electron diffraction (SAED). A crystallographic orientation regulation, i.e. the adjacent 1-5 calcite prisms with the same three-dimensional orientation in the oblique prismatic layer, was found for the first time. It is observed that the calcite prisms in the oblique prismatic layer were grown with their (104) parallel to the shell surface.