The Effect and Characteristics on Chitosan Nanoparticles with Different Concentration of TPP

Chitosan nanoparticles (CS NPs) was prepared by mixed with TPP for drug release carrier in this study. Generally, Chitosan is a good and non-toxic biodegradable polysaccharide polymer with low immunogenicity. Tripolyphosphate (TPP) is a polyanion, and can interact with cationic chitosan by electrostatic forces. So Chitosan/TPP nanocomposites were synthesized Berberine, a naturally occurring isoquinoline alkaloid, was shown to have anti-inflammatory and anti-tumour properties in vitro systems. And we have used the transmission electron micro-graphs (TEM) and Dynamic light scattering (DLS) to gain the CS nanoparticles’ size. The action of tripolyphosphoric groups of TPP crosslinked with ammonium groups on chitosan in the nanoparticles and it was identified by FTIR. We also obtained the poison property of berberine mantled by CS NPs to human breast cancer cell.

3-Dimentional Observation of Lamellar Structure of a High Density Polyethylene Using Transmission Electron Micro-tomography

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005

Low-Temperature (630°C) Epitaxy of Silicon on Seeded Glass by Ion-Assisted Deposition

ABSTRACTThin polycrystalline silicon (poly-Si) films on glass are of great interest for electronic and photovoltaic applications. In this paper we report the successful realisation of thick (5 microns), large-grained (5 microns), continuous and smooth poly-Si films on glass at a temperature below 700°C. This significant technological milestone was achieved by using ion-assisted deposition (IAD) of silicon at 630°C for thickening a thin poly-Si seeding layer made on the glass at about 500°C by aluminium-induced crystallisation of amorphous silicon. Transmission electron micro-graphs reveal an epitaxial relation between about 50% of the grains of the IAD-grown layer and the seeding layer, while the remainder grew with a different orientation than the seed grains. The grain size of the IAD-grown poly-Si film is determined by the grain size of the underlying polySi seeding layer, a clear experimental proof of the “seeding layer concept”.

A novel UHV-REM as applied to observation of reconstruction of Pt(100) surface

Direct observation of surface reconstruction under reflection electron micros-copy(REM) provides an intimate insight into basic processes on the surface, leading to more comprehensive understanding of surface physics in atomic scale. For this purpose we have developed a special UHV-specimen chamber, which allows various types of attachments, e.g., evaporator, ion gun, cooling facility, gas inlet and STM if necessary, to be mounted. This chamber was mounted in a 200kV transmission electron micro scope(TEM), Hitachi H-700H, to construct a novel UHV-REM for surface study.Fig.l shows a schematic diagram of the UHV-TEM constructed in the present work. The specimen chamber is evacuated with turbomolecular pump and Ti sublimation pump to the vacuum pressure of ~10-9 Torr. Some additional ports for, evaporator, gas-inlet, etc. are also attached around the specimen stage. Feedthrough metal bellows for driving system allows specimen holder to be translated in X- and Y-directions and to be tilted against electron beam without deterioration of vacuum pressure.