Bacterial cellulose/hyaluronic acid composites have been prepared by the nontoxic cross-linking agent 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide. The effects of hyaluronic acid concentration, temperature, and the 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide addition way on the performance of the composites have been discussed. Field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analyzer have been used to characterize the composite materials. The hyaluronic acid contents in the composites have been assayed by a colorimetric method. Hyaluronic acid concentration, the 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide addition way, and temperature have impacts on the hyaluronic acid content in composites. Fourier transform infrared spectra confirm the amide groups on the composites, which is attributed to hyaluronic acid molecules. The crystallinity indexes of composites decrease, in comparison with pristine bacterial cellulose, known from X-ray diffraction tests, possibly due to the integration of hyaluronic acid. The thermal decomposition temperatures of Composites A and B from Process 1 are lower than those of bacterial cellulose, which is ascribed to lower pyrolysis temperatures of hyaluronic acid compound in composite materials. However, Composites C and D from Process 2 do not undergo descent thermal stability. The novel nanocomposites have the potential to be used for biomedical and tissue engineering scaffold materials.

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Plate-type fuel elements is one of the first fuel structure choice for the novel integrated PWR, however, blisters will appear on the cladding induced by irradiation and fission. In this work CFD method was used to investigate the subcooled boiling characteristic of the water in rectangle channel with round and pillow blisters, the modified RPI model was also proposed, we can draw conclusions as follows: In the channel with round blister, as the blisters will increase the local flow resistance and more fluid will flow through center of the channel. Boiling occurred only in the area near the edges, nearly no vapor appeared at the center of the channel. The boiling region in channel with pillow shape blisters is wider and concentrated between two pillow blisters and downstream of the non-blisters side. The dry out area are both in the downstream region of blisters for the two types of channels.

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