QCM Detection of Adhesion, Spreading and Proliferation of Human Breast Cancer Cells （MCF-7） on a Gold Surface

The quartz crystal microbalance (QCM) was used to monitor the one-day incubation of human breast cancer cells (MCF-7) on the gold electrode. In combination with an optical microscope simulation experiment, the cell-population pictures at various stages, the QCM responses to the cells' adhesion, spreading and proliferation on the electrode surface were discussed. The △f0 and △R1 responses were found mainly from mixed effects of viscodensity and surface stress, and in proportion to the cell coverage, rather than to the number of cells at the electrode. The significant fore-and-aft changes in cyclic voltammetry and electrochemical impedance spectroscopy of the ferri-ferrocyanide redox couple also proved that the cells were adhesion to the gold surface.     

Synthesis, Crystal Structure and Electrochemical Properties of One-dimensional Chain Coordination Polymer [Co（Ⅱ）（C6H5CH=CHCOOH）2（4,4＇-bipy）（H2O）5]n

A one-dimensional chain coordination polymer [Co（Ⅱ）（C6H5CH--CHCOOH）2（4,4＇- bipy）（H20）5]n has been synthesized with cinnamylic acid, 4,4＇-bipy and cobaltous chloride as raw materials. Crystal data for this complex： monoclinic, space group P21/c, a = 1.1481（3）, b = 1.1230（2）, c = 1.1759（3） nm, β = 97.054（4）^o, V= 1.5046（6） nm^3, Mr= 617.50, Dc = 1.363 g/cm^3, Z = 2, ,u（MoKa） = 0.627 mm^-1, F（000） = 646, S = 1.062, R 0.0443 and wR = 0.1178. The crystal structure shows that two neighboring cobalt（ID ions are linked together by one 4,4＇-bipy, and the whole complex molecule adopts a one-dimensional chain structure. Each cobalt（H） ion is coordinated with two nitrogen atoms from two 4,4＇-bipy molecules and four oxygen atoms from four water molecules, giving a distorted octahedral coordination geometry. The electrochemical properties were analyzed by combining with the crystal structure.     

Gold Nanoparticle-based Layer-by-Layer Enhancement of DNA Hybridization Electrochemical Signal at Carbon Nanotube Modified Carbon Paste Electrode

Nanoporous materials have been widely applied to biosensor investigation. Recently, Guo et al. have investigated the mesoporous materials modified carbon paste electrode for rapid cTnI (cardiac troponin I) detection with enhanced sensitivity1-3. However, …     

Determination of Active Ingredients of Hawthorn by Capillary Electrophoresis with Electrochemical Detection

A method based on capillary electrophoresis with electrochemical detection has been developed for the separa-tion and determination of epicatechin,kaempferol,chlorogenic acid,4-hydroxybenzoic acid,quercetin and proto-catechuic acid in hawthorn for the first time.The effects of working electrode potential,pH and concentration ofrunning buffer,separation voltage and injection time on CE-ED were investigated.Under the optimum conditions,the analytes could be separated in a 60 mmol·L~(-1) borate buffer(pH 8.7)within 21 min.A 300 μm diameter carbondisk electrode has a good response at 0.95 V(vs.SCE)for all analytes.The response was linear over three ordersof magnitude with detection limits(S/N=3)ranging from 3×10~(-8) to 2×10~(-7) g·mL~(-1) for the analytes.The methodhas been successfully applied to the analysis of real sample,with satisfactory results.     

半晶化双螺旋介孔MnO2的合成和电化学性质

Mesoporous silica KIT-6 has novel three-dimensional gyroidal channel structure, space group of 1a-3d, and ordered tunable pores up to 10 nm. In this paper, such mesostructured silica was employed as hard template to prepare semicrystalline gyroidal mesoporous MnO2. The structure was investigated by XRD, TEM and HRTEM, and found to be of high quality 1a-3d symmetry, in good accordance with the template structure. The material has a BET surface of 118 m2·g^-1 and pore volume of 0.35 cm3·g^- 1 after eliminating template. Mesoporous MnO2 has shown good electrochemical property as supercapacitor material in 1 mol·L^-1 Na2SO4 and 1 mol·L^-1 LiClO4 solutions, but interesting pseudocapacitance behavior was observed in the case of 6 mol·L^-1 KOH. It was found that mesoporous MnO2 performed stable reversible electrochemical behavior with capacitance of 220 F·g^-1 in a potential range of -0.1-0.55 V vs. Hg/HgO in alkaline solution, demonstrating that it is a promising novel electrode material for the fabrication of electrochemical capacitors.     

淩鸿勋的这一“点”和那一“钩”

正凌、淩,两个字,音同字不同,笔划差一"点"。在1948年当选的院士中,有一位淩鸿勋。长时期以来,我,绝非只是我,一直是在下笔之时把他的姓氏搞错了的。淩鸿勋(1894~1981年),字竹铭,广东番禺人,铁道工程专家。1915年毕业于上海工业专门学校(交通大学之前身),后赴美实习进修。自1918年归国后的几十年中,对中国铁路建设事业贡献卓著。1950年去台,1971年退休前为中油公司董事长,1981年8月在台北去世。我最早是从1948年的《国立中央研究院概况》中见到淩鸿勋这个名字的,后来读了     

桥上CRTS Ⅱ型板式无砟轨道均匀温度研究

在某客运专线曲线段桥上设置温度传感器,通过对CRTSⅡ型板式无砟轨道进行长达两年的监控,得到其时变规律,利用时间序列差分法求得测点日平均温度,得到代表整体温度变化趋势的均匀温度时程曲线,有效反映了结构温度随大气的季节性变化规律.基于傅立叶曲线拟合及高阶矩统计模型研究其规律,提出无砟轨道整体的均匀温度变化规律.结果表明,结构各测点均匀温度呈现以365d为周期的三角函数变化规律,其拟合参数可分别表示均匀温度变化规律中的中位值、幅值及相位差;各测点间的均匀温度拟合结果差异较小,可将轨道全截面作为一整体分析,用其统一温度代表轨道整体的均匀温度变化规律;通过高阶矩概率统计模型对统一温度分析,可得到具有概率保证的均匀温度变化方程.     

茅于轼获弗里德曼自由奖

正一个被极左派痛恨、被自由派推崇的经济学家。美国智库卡托研究所(Cato Institute)3月29日宣布,茅于轼获得该研究所颁发的2012年弗里德曼自由奖,奖金为25万美元。弗里德曼自由奖设立于2002年,每两年评选一次,今年的颁奖仪式将于5月4日在美国华盛顿市举行。获奖后,茅于轼表示:"CATO给我这个奖,说明中国在自由争取方面有了很大成功。跟其他发展中国家比,中国在这方面的成功是很了不起的。其中有我们的一份     

太原北站专用铁道安全管理现状及对策研究

介绍了太原北站的基本情况,结合近年来太原北站专用铁道安全管理的实际状况,分析了安全管理中存在的问题,并提出了解决对策。