生物分子功能化碳纳米管

利用生物分子功能化碳纳米管,使其具备生物相容性和特殊的识别功能并引入生物体系是一项极具应用潜力的研究.如何利用不同种类的生物分子功能化碳纳米管则是该领域须解决的一个关键问题.本文综述了利用生物分子酶、蛋白质、氨基酸、肽螺旋、DNA功能化碳纳米管的最新研究进展,重点介绍了碳纳米管侧壁与端口的DNA功能化以及碳纳米管的DNA填充,并对DNA功能化碳纳米管在生物传感器、电化学检测及DNA操纵碳纳米管自组装方面的应用作了阐述.     

基于改进型高斯混合模型的嵌入式实时运动检测系统

针对在嵌入式CPU上难以做到复杂背景下运动目标的实时检测,提出了一种基于改进型高斯混合模型的实时运动检测方案,采用改进型高斯混合模型,对高斯混合模型进行简化和结构调整,同时进行了C语言层面和CPU层级的优化,使其更合适于嵌入式平台,并详细分析了DM6446平台的软硬件设计,介绍了该算法在DM6446平台上的实现过程。实验结果表明：该系统能够有效克服外界环境变化带来的干扰,能够实时检测,可以实现多目标跟踪。     

介孔氧化铝净化-气相色谱法同时测定蔬菜、水果及茶叶中16种有机磷农药残留

利用气相色谱检测技术,建立了能应用于白菜、生菜、南瓜、洋葱、番茄、白萝卜、苹果、梨及茶叶等不同基质中16种有机磷农药残留的检测方法。样品采用乙酸乙酯提取,经以合成的介孔氧化铝作吸附剂的固相萃取柱净化,DB-1701毛细管柱分离,气相色谱-火焰光度检测器检测。结果表明,蔬菜、水果及茶叶基质中16种有机磷农药在10~2000 μg/L范围内具有良好的线性关系（R²>0.997）;平均回收率为83.2%~103.8%,相对标准偏差为2.0%~9.9%。该方法灵敏度高、准确度高、重复性好,可适用于蔬菜、水果及茶叶基质中16种有机磷残留量的同时测定。     

Study on the determination of polyphenols in tobacco by HPLC coupled with ESI-MS after solid-phase extraction

A high-performance liquid chromatography method coupled with electrospray ionization-mass spectrometry for the determination of polyphenols in tobacco is studied. The polyphenols are extracted from a tobacco sample by being refluxed in a boiling water bath with 80% methanol and purified by solid-phase extraction with a C18 cartridge. The chlorogenic acid, rutin, scopoletin, caffeic acid, scopolin, and other polyphenols are satisfactorily separated on a Nova-Pak C18 chromatographic column (3.9 x 150 mm) with methanol and 0.05 mol/L potassium dihydrogen phosphate buffer solution gradient elution as mobile phase at a flow rate of 0.5 mL/min. Each of the polyphenols is monitored by photodiode array detector at its maximum wavelength: chlorogenic acid, 326.1 nm; rutin, 354.8 nm; scopoletin, 344.0 nm; caffeic acid, 323.7 nm; and scopolin, 365.2 nm. The limits of detection are: 100 ng/mL for chlorogenic acid, 125 ng/mL for rutin, 60 ng/mL for scopoletin, 50 ng/mL for caffeic acid, and 100 ng/mL for scopolin. The key polyphenols in tobacco are identified by comparing the retention time, the UV-spectrum, and the mass spectra with those of the standards. The recovery of tobacco polyphenols is 94-105%, and the relative standard deviations are 1.28-1.49%. This method is successfully applied to qualitatively and quantitatively analyze the polyphenols in tobacco with good results.     

纳米镍修饰TiO2纳米管电极检测胰岛素

采用阳极氧化法制备出高度有序的TiO2纳米管阵列作为基础电极,通过电沉积法将纳米镍颗粒负载在基础电极上,从而制备了纳米镍-二氧化钛纳米管(Ni/TiO2NTs)修饰电极。分别采用扫描电子显微镜和X射线衍射对Ni/TiO2NTs电极的形貌及组分进行了表征。将Ni/TiO2NTs电极用于对胰岛素的电化学测定。结果表明,在0.1 mol/L NaOH支持电解液中,胰岛素在Ni/TiO2NTs电极上有较好的电化学响应,胰岛素浓度在0.8～1.6μmol/L范围内,峰电流密度与其浓度呈良好的线性关系,检测限为0.28μmol/L,灵敏度为0.49×10-3 A/(μmol·L-1.cm-2)。     

13C核磁共振解析甙类化合物中糖的连接方式

根据葡萄双糖的¹³C化学位移数据,用统计的方法找出糖的构型和连接方式对化学位移影响的经验规律和常数,把它们有条件地推广到甙类化合物中的低聚糖体系中去,推引了一些计算这些低聚糖体系中糖碳化学位移值的经验公式,并用来指定某些甙类化合物中糖碳中的化学位移,得到比较令人满意的结果     

拓展大学化学习题功能的尝试

习题在教学过程中起着举足轻重的作用,对此,邢其毅教授发表过精辟的见解。他说;“习题的基本价值在于解决问题过程的基本训练。一个有水平的习题,应该既能将学生学过的各种知识巧妙地结合起来,引导学生将所学的知识融会贯通;也能告诉学生理论知识是如何应用于实际的,以提高学生     

Solid Phase Extraction and Spectrophotometric Determination of Mercury in Tobacco and Tobacco Additives with p-Sulfobenzylidenerhodanine as Chromogenic Reagent

A highly sensitive, selective and rapid method for the determination of mercury based on the reaction of mercury(II) with p-sulfobenzylidenerhodanine (SBDR) and the solid phase extraction of the colored chelate with a C₁₈ cartridge has been developed. In the presence of pH 3.8 acetate buffer solution and Tween-80 medium, SBDR reacts with mercury to form a red chelate of a molar ratio of 1:2 (mercury to SBDR). This chelate was enriched by solid phase extraction with a C₁₈ cartridge and eluted from the cartridge with ethanol (containing 5% acetic acid). The enrichment factor of 50 was achieved. In the ethanol medium, the molar absorptivity of the chelate is 1.28×10⁵L·mol^–1·cm^–1 at 545nm. Beers law is obeyed in the range of 0.011.2µgmL^–1 in the measured solution. The relative standard deviation for eleven replicate samples of 0.01µgmL^–1 level is 1.52%. This method can be applied to the determination of mercury in tobacco and tobacco additives with good results.     

聚吡咯/TiO2纳米管阵列复合电极制备条件对其光电性能的影响

通过阳极氧化法制备TiO2纳米管阵列(TNTA),静态下采用电化学方法在TNTA表面修饰聚吡咯(PPy)。并用扫描电子显微镜(SEM)、红外透射光谱(FTIR)、紫外可见漫反射吸收光谱(UV-Vis)等表征手段对复合材料进行表征。结果显示,PPy和TiO2之间存在强烈的相互作用,PPy修饰的TNTA发生了红移,并且增强了其在整个可见光区的吸收。确定了影响PPy/TNTA复合电极光电性能的因素(聚合时间、聚合温度、聚合电位、电解质浓度等),通过测定连续瞬间电流-时间曲线的方法,考察了制备条件对复合材料光电性能的影响。初步探讨出PPy提高TNTA光电性能的机理。