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Water-soluble, biological-compatible, and excellent fluorescent CdSe/CdS quantum dots (QDs) with L-cysteine as capping agent were synthesized in aqueous medium. Fluorescence (FL) spectra, absorption spectra, and transmission electron microscopy (TEM) were employed to investigate the quality of the products. The interactions between QDs and bovine serum albumin (BSA) were studied by absorption and FL titration experiments. With addition of QDs, the FL intensity of BSA was significantly quenched which can be explained by static mechanism in nature. When BSA was added to the solution of QDs, FL intensity of QDs was faintly quenched. Fluorescent imaging suggests that QDs can be designed as a probe to label the Escherchia coli (E. coli) cells. These results indicate CdSe/CdS/L-cysteine QDs can be used as a probe for labeling biological molecule and bacteria cells.

Visible-light-driven Ag/AgBr/TiO /activated carbon (AC) composite was prepared by solgel method coupled with photoreduction method. For comparison, TiO , TiO /AC, and Ag/AgBr/TiO were also synthesized. Their characteristics were analyzed by XRD, SEM-EDS, TG-DSC and UV-vis techniques. Photocatalytic activity and antibacterial performance under visible-light irradiation were investigated by ICP-AES, ATR-FT-IR and spectrophotometry methods using methylene blue and Escherichia coli as target systems, respectively. The results showed that Ag/AgBr was successfully deposited on anatase TiO /AC surface, and exhibited a distinct light absorption in the visible region. Ag/AgBr/TiO /AC displayed excellent antibacterial performance both in dark and under visible-light illumination. The growth of E. coli cell was inhibited in the presence of Ag/AgBr/TiO /AC in dark. Moreover, upon visible-light illumination, a significant damage of cell membrane was noticed. Ag/AgBr/TiO /AC was also shown higher photocatalytic efficiency for methylene blue degradation than those of TiO , TiO /AC, and Ag/AgBr/TiO . This is attributed to the synergetic effect between AC and Ag/AgBr/TiO , of which AC acts as the role of increasing reaction areas, continuous enriching, and transferring the adsorbed MB molecules to the surface of supported photocatalysts, and the Ag/AgBr/TiO acts as a highly active photocatalyst for degrading MB molecules under visible-light irradiation.

Abstract-The idea of "to educate people with courtesy and to foster people with morality" is integrated into the ideological and political educational model for college students, so as to clearly know the theory bases, activate practice, and deeply implement the spiritual education. It is incorporated into the four-year college ideological and political educational period by steps and stages based on the specific contents and requirements (i.e. filial piety; love and respect one's elder