Aim To separate high purity linolenic acid from the oil of Lithospermumerythrorhizon growing in the Northeast of China. Methods Urea inclusion and column chromatographywere used. Results Unsaturated fatty acid was sep...Aim To separate high purity linolenic acid from the oil of Lithospermumerythrorhizon growing in the Northeast of China. Methods Urea inclusion and column chromatographywere used. Results Unsaturated fatty acid was separated, with a purity of 99.30 wt% of linolenicacid. Conclusion The experiment shows excellent reproducibility and high feasibility for industrialproduction.展开更多
Aim To investigate the anticancer activity of two new cytotoxins from thevenom of Agkistrodon acutus. Methods The venom was isolated by FPLC column chromatography consistingof DEAE Sepharose FF and Source 30S. The cyt...Aim To investigate the anticancer activity of two new cytotoxins from thevenom of Agkistrodon acutus. Methods The venom was isolated by FPLC column chromatography consistingof DEAE Sepharose FF and Source 30S. The cytotoxic activity on tumor cells was detected by MITmethod. Purity and molecular weight were determined by SDS-PAGE (silver staining). Their stabilitiesto temperature and pH were also detected. Results Two pure cytotoxins named ACTX-6 and ACTX-8 wereobtained. Their molecular weights are 98 kDa and 27 kDa, respectively. ACTX-6 consists of twosubunits bonded together by disulfide bonds. Conclusion ACTX-6 and ATCX-8 have highest inhibitoryactivity on lung cancer cell A549. ACTX-6 is stable to heat while ACTX-8 not. ACTX-6 is stablebetween pH 7-9 and ACTX-8 between pH 6 - 9.展开更多
Due to their excellent electrical properties and compatibility with room-temperature deposition/printing processing, high-purity single-walled semiconducting carbon nanotubes hold great potential for macroelectronic a...Due to their excellent electrical properties and compatibility with room-temperature deposition/printing processing, high-purity single-walled semiconducting carbon nanotubes hold great potential for macroelectronic applications such as in thin-film transistors and display back-panel electronics. However, the relative advantages and disadvantages of various nanotubes for macroelectronics remains an open issue, despite the great significance. Here in this paper, we report a com- parative and systematic study of three kinds of mainstream carbon nanotubes (arc-discharge, HiPCO, CoMoCAT) separated using low-cost gel-based column chromatography for thin-film transistor applications, and high performance transistors--which satisfy the requirements for transistors used in active matrix organic light-emitting diode displays--have been achieved. We observe a trade-off between transistor mobility and on/off ratio depending on the nanotube diameter. While arc-discharge nanotubes with larger diameters lead to high device mobility, HiPCO and CoMoCAT nanotubes with smaller diameters can provide high on/off ratios (〉 106) for transistors with comparable dimensions. Furthermore, we have also compared gel-based separated nanotubes with nanotubes separated using the density gradient ultracentrifuge (DGU) method, and find that gel-separated nanotubes can offer purity and thin-film transistor performance as good as DGU-separated nanotubes. Our approach can serve as the critical foundation for future carbon nanotube-based thin-film macroelectronics.展开更多
文摘Aim To separate high purity linolenic acid from the oil of Lithospermumerythrorhizon growing in the Northeast of China. Methods Urea inclusion and column chromatographywere used. Results Unsaturated fatty acid was separated, with a purity of 99.30 wt% of linolenicacid. Conclusion The experiment shows excellent reproducibility and high feasibility for industrialproduction.
文摘Aim To investigate the anticancer activity of two new cytotoxins from thevenom of Agkistrodon acutus. Methods The venom was isolated by FPLC column chromatography consistingof DEAE Sepharose FF and Source 30S. The cytotoxic activity on tumor cells was detected by MITmethod. Purity and molecular weight were determined by SDS-PAGE (silver staining). Their stabilitiesto temperature and pH were also detected. Results Two pure cytotoxins named ACTX-6 and ACTX-8 wereobtained. Their molecular weights are 98 kDa and 27 kDa, respectively. ACTX-6 consists of twosubunits bonded together by disulfide bonds. Conclusion ACTX-6 and ATCX-8 have highest inhibitoryactivity on lung cancer cell A549. ACTX-6 is stable to heat while ACTX-8 not. ACTX-6 is stablebetween pH 7-9 and ACTX-8 between pH 6 - 9.
文摘Due to their excellent electrical properties and compatibility with room-temperature deposition/printing processing, high-purity single-walled semiconducting carbon nanotubes hold great potential for macroelectronic applications such as in thin-film transistors and display back-panel electronics. However, the relative advantages and disadvantages of various nanotubes for macroelectronics remains an open issue, despite the great significance. Here in this paper, we report a com- parative and systematic study of three kinds of mainstream carbon nanotubes (arc-discharge, HiPCO, CoMoCAT) separated using low-cost gel-based column chromatography for thin-film transistor applications, and high performance transistors--which satisfy the requirements for transistors used in active matrix organic light-emitting diode displays--have been achieved. We observe a trade-off between transistor mobility and on/off ratio depending on the nanotube diameter. While arc-discharge nanotubes with larger diameters lead to high device mobility, HiPCO and CoMoCAT nanotubes with smaller diameters can provide high on/off ratios (〉 106) for transistors with comparable dimensions. Furthermore, we have also compared gel-based separated nanotubes with nanotubes separated using the density gradient ultracentrifuge (DGU) method, and find that gel-separated nanotubes can offer purity and thin-film transistor performance as good as DGU-separated nanotubes. Our approach can serve as the critical foundation for future carbon nanotube-based thin-film macroelectronics.