Naturally derived collagen protein was mixed thoroughly with medical grade poly (vinyl alcohol) (PVA) at the ratio of 90:10 (w/w) and was crosslinked by formaldehyde to form a homogeneous composite membrane. The bulk ...Naturally derived collagen protein was mixed thoroughly with medical grade poly (vinyl alcohol) (PVA) at the ratio of 90:10 (w/w) and was crosslinked by formaldehyde to form a homogeneous composite membrane. The bulk structure of the membrane was characterized by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The membrane surface structure was investigated using Fourier transform-infrared spectroscopy (attenuated total refraction) (FTIR-ATR), electron spectroscopy for chemical analysis (ESCA) and contact angle measurement. It was found that collagen and PVA can remain stable. This was supported by the fact that no sign of phase separation had been observed. The use of crosslinking agent can substantially influence the structure of the composite. It is suggested that this new composite deserves further investigation and is potentially usable as a biomedical material.展开更多
The regular and smooth objects are always studied in conventional geometry. But very rough and irregular objects which have self-similarity, the fractal structure, are efficiently solved by fractal geometry. The self-...The regular and smooth objects are always studied in conventional geometry. But very rough and irregular objects which have self-similarity, the fractal structure, are efficiently solved by fractal geometry. The self-similarity is that the local configuration is similar to the whole configuration. In other words, for each resolution scalar, the form of the curves is similar. Fractal structure exists widely in nature. In this note, band-limited fractal functions展开更多
文摘Naturally derived collagen protein was mixed thoroughly with medical grade poly (vinyl alcohol) (PVA) at the ratio of 90:10 (w/w) and was crosslinked by formaldehyde to form a homogeneous composite membrane. The bulk structure of the membrane was characterized by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The membrane surface structure was investigated using Fourier transform-infrared spectroscopy (attenuated total refraction) (FTIR-ATR), electron spectroscopy for chemical analysis (ESCA) and contact angle measurement. It was found that collagen and PVA can remain stable. This was supported by the fact that no sign of phase separation had been observed. The use of crosslinking agent can substantially influence the structure of the composite. It is suggested that this new composite deserves further investigation and is potentially usable as a biomedical material.
文摘The regular and smooth objects are always studied in conventional geometry. But very rough and irregular objects which have self-similarity, the fractal structure, are efficiently solved by fractal geometry. The self-similarity is that the local configuration is similar to the whole configuration. In other words, for each resolution scalar, the form of the curves is similar. Fractal structure exists widely in nature. In this note, band-limited fractal functions
