A versatile chemical conversion synthesis of Cu2S nanotubes and the photovoltaic activities for dye-sensitized solar cell

A versatile, low-temperature, and low-cost chemical conversion synthesis has been developed to prepare copper sulfide (Cu₂S) nanotubes. The successful chemical conversion from ZnS nanotubes to Cu₂S ones profits by the large difference in solubility between ZnS and Cu₂S. The morphology, structure, and composition of the yielded products have been examined by field-emission scanning electron microscopy, transmission electron microscopy, and X-ray diffraction measurements. We have further successfully employed the obtained Cu₂S nanotubes as counter electrodes in dye-sensitized solar cells. The light-to-electricity conversion results show that the Cu₂S nanostructures exhibit high photovoltaic conversion efficiency due to the increased surface area and the good electrocatalytical activity of Cu₂S. The present chemical route provides a simple way to synthesize Cu₂S nanotubes with a high surface area for nanodevice applications.     

2008,中国石材贸易在艰辛与努力中迈向55亿美元

2008年中国石材贸易可以用"人民币汇率不断升值,严重影响了石材企业出口和国内效益;作为世界石材最大出口国,且多年位居全国建材单一产品创汇最多的行业,2008年中国石材贸易仍不畏艰险、挺立鳌头、逆风飞扬,贸易较上年仍有较大增长;石材出口效益剧跌,首次凸显"个位数"增长;进口石材结构发生显著变化,外汇支出明显增加;国内大理石深加工势头放缓,行业发展传出调整信息."这样几句话来概括.     

Effect of Phenolic Acid on Antioxidant Activity of Wine and Inhibition of Pectin Methyl Esterase

Antioxidant activity, malolactic fermentation and sensory evaluation of the grape must after fermentation in the presence of gallic acid and coumaric acid, as well as the inhibitory mechanism of gallic acid and coumaric acid on pectin methyl esterase (PME), were investigated. The content of malic acid and lactic acid increased 40.4% and 36.9% compared to the control when commercial pectic enzyme (CPE) was used. The increase in malic acid content was enhanced by 64.8% and 83.4%, compared to the control in the presence of CPE + Gallic acid and CPE + Coumaric acid respectively. Ferric reducing/antioxidant power (FRAP) increased in the samples with added CPE. In addition to an increase in the FRAP, antioxidant capacity was enhanced in the CPE + Gallic acid and CPE + Coumaric acid samples. No significant differences were found in the content of total anthocyanin and in the value of sensory characteristics. The content of total flavanols increased significantly in the samples with added CPE. Lineweaver‐Burk plots of PME, with gallic acid or coumaric acid, indicated that gallic acid and coumaric acid were mixed inhibitors of PME.     

圆柱凸轮参数化建模方法研究

SolidWorks软件具有强大的曲面、实体建模能力,利用其成熟的三维技术,结合圆柱凸轮的机构特点,分别采用三种方法实现了一种圆柱凸轮的参数化建模,并验证了此三维模型。通过对建模方法的比较,找出了一种最简洁,灵活,实用的全参数化方法,对建立其他形式复杂圆柱凸轮参数化模型具有一定的参考价值。     

Expression and purification of beefy meaty peptide in <Emphasis Type="Italic">Pichia pastoris</Emphasis>

We established a gene expression process to produce a flavor peptide in Pichia pastoris. The octapeptide Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala was isolated from beef digested by papain, known as “beefy meaty peptide” (BMP). It was considered a savory seasoning in previous literatures. To produce BMP by microorganisms, BMP expression structures encoding tandem repeats of the octapeptide were designed and cloned in E. coli DH5α, then integrated into the AOX1 gene of Pichia pastoris GS115. Clones containing different BMP-gene copies, with 4-copy, 8-copy, 12-copy and 16-copy, were obtained and expressed in Pichia pastoris GS115. For the ease of purification, 6×His tag was fused to the C-termini of the peptides. As a result, the fusion peptides were successfully purified by His-tag bind affinity resin. The BMP fusion peptides with expected sizes were secreted from the resulting strains of P. pastoris GS115.     

苏州市城市交通系统生态化现状评价及对策建议

城市交通系统的生态化发展是实现城市交通可持续发展的必然要求。文章从生态交通的安全、健康、高效、舒适四个方面对苏州市交通系统生态化进行现状评价,提出制定生态化的城市交通系统规划、构建生态化的城市交通结构、实施生态化的城市交通管理以及鼓励公众参与的对策建议。     

“Click” Synthesis of a Heterobifunctional Ferrocenyl Dendrimer with Molecular Recognition Properties and Influence of the Ferrocenyl Redox Potential on the Formation of Gold Nanoparticles

Alkyne protection by complexation of ethynylferrocene with dicobalt octacarbonyl followed by regioselective acetylation, then deprotection and “click” reaction with a nona-azido-terminated arene-cored dendrimer leads to the heterodifunctional nona(1,2,3-triazolyl-acetylferrocenyl) dendrimer. Cyclic voltammetry of this metallodendrimer shows recognition of both ATP^2? and Pd²⁺. HAuCl₄ is reduced much more slowly to gold nanoparticles by the nona(triazolyl-acetylferrocenyl dendrimer than by the nona(triazolylferrocenyl) dendrimer due to the shift of redox potential in the new heterodifunctional dendrimer compared to that of the parent ferrocenyl dendrimer.     

财务管理沙盘模拟在非财务人员培训中的应用

沙盘模拟教学是一种全新的教学方式。通过财务管理沙盘模拟培训体系在非财务人员培训班的实施，具体介绍了实施过程中取得的宝贵经验，指出了沙盘模拟培训中存在的若干问题，给出了解决问题的相关对策。