Ordered Mesoporous Carbon/Graphene/Nickel Foam for Flexible Dopamine Detection with Ultrahigh Sensitivity and Selectivity

柔性生物传感器在可穿戴电子设备中有着广泛的应用前景. 为了获得柔性电化学多巴胺传感器,作者在本工作中首先在镍泡沫表面通过化学气相沉积生长石墨烯,随后通过高温碳化嵌段共聚物与酚醛树脂在石墨烯表面共组装形成的薄膜制备了有序介孔碳/石墨烯/镍泡沫（OMC/G/Ni）复合材料. 其中,镍泡沫可以为复合材料提供具有高导电性和良好柔韧性的金属骨架,而具有垂直排列介孔阵列的有序介孔碳层为复合材料提供了高的电活性表面积,且有利于活性位点的暴露. 值得注意的是,夹在有序介孔碳层和镍泡沫之间的石墨烯极大地增强了各组分之间的相容性,有利于进一步提升复合材料的电化学性能. 作为电化学传感器中的工作电极,OMC/G/Ni体现出优异的多巴胺检测能力. 不但具有宽的线性检测范围（0.05 ~ 58.75 μmol·L-1）和低检测限（0.019 μmol·L-1）,还具有良好的选择性、重现性和稳定性. 此外,OMC/G/Ni在弯曲状态下依旧能够保持对多巴胺的高检测能力,证明了其在柔性生物传感器中的应用潜力.Flexible biosensors have received intensive attentions for their potential applications in wearable electronics. To obtain flexible electrochemical dopamine (DA) sensors, the ordered mesoporous carbon/graphene/nickel foam (OMC/G/Ni) composite was fabricated in this work via the growth of graphene on Ni foam by chemical vapor deposition, and the formation of the OMC layer followed by the carbonization of co-assembled resol and block polymer., The monolithic Ni foam in the resultant OMC/G/Ni electrode provided an interconnected metal framework with high conductivity and good flexibility, while the OMC layer with the vertically aligned mesopore arrays rendered the composite a large electroactive surface with highly exposed active sites. More importantly, the graphene sandwiched between the OMC layer and Ni foam greatly enhanced the compatibility of each component. As the integrated electrode in DA sensor, the OMC/G/Ni electrode exhibited excellent performances with a large linear detection range (0.05 ~ 58.75 μmol·L-1), an ultra-low detection limit (0.019 μmol·L-1), high selectivity, good reproducibility and high stability, outperforming the recently reported flexible DA sensors. Moreover, the OMC/G/Ni electrode still kept the good DA sensing behavior at its bent states, demonstrating its potential for flexible biosensors.通讯作者:刘瑞丽E-mail:[email protected]:LIURui-liE-mail:[email protected]. 上海交通大学电子工程系,上海 2002402. 上海交通大学化学化工学院,上海 2002401. Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China2. School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai,200240, P. R. Chin

Thermodynamic calculation of phase equilibria in Cu-Ni-Sn ternary system

[中文文摘]基于Cu-Ni-Sn三元系的相平衡和热力学的实验信息,采用亚正规溶体模型描述液相和fcc相的Gibbs自由能,为了预测该体系中bcc相的A2 B2有序无序转变,bcc相的Gibbs自由能采用双亚点阵模型进行描述。利用CALPHAD(相图计算)方法评估了Cu-Ni-Sn三元系各相的热力学参数,计算的富Cu侧相图和热力学性质与实验数据比较一致。并对该三元系中bcc相的A2 B2有序无序转变及fcc相的溶解度间隙进行了计算。这些计算结果对利用析出强化以及Spinodal分解开发高强度和高导电性的新型Cu基合金的组织设计具有一定的指导意义。[英文文摘]On basis of the phase equilibria and thermodynamic properties of the Cu-Ni-Sn ternary system by experiment,the thermodynamic assessment of the Cu-Ni-Sn ternary system was carried out by the CALPHAD(calculation of phase diagrams) method.The Gibbs free energies of liquid and fcc phases were described by the subregular solution model,and Gibbs free energies of the bcc phase were described by the sublattice model in order to predict the order-disorder phase transition in the bcc phase.A set of parameters parameters describing the Gibbs energies of different phases in this system were optimized by experimental data. The calculated result s agree well the experimental data. The A2/B2 ordering temperature and miscibility gap of the fcc phase can be predicted. These calculated result s provide an effective guide for microst ructure design of the new type Cu base practical materials with high strength and high electric conductivity.国家杰出青年科学基金资助项目(50425101); 教育部科学技术研究重点资助项目(105100)

液相不溶型合金复合组织自形成驱动力的解析

利用Becker提出的计算界面能的方法 ,计算了液相不溶体系中两液相的界面能 ,并基于Gibbs Thomson关系式 ,对整个析出液相和基体液相之间的表面能进行积分 ,得到了在冷却过程中作用在液滴上指向试样中心的力 ,它是半径和温度梯度的函数 .除了上述的作用力外 ,重力和浮力也同时作用在液滴上 .这些力的合力是形成该类型复合组织的主要原因 .该方法应用到Fe Cu合金系 ,进行了计算 ,与实验结果符合得很好.国家自然科学基金(批准号:50271027); 福建省国际合作(2002I018); 福建省自然科学基金(E0310023); 福建省青年创新基金(2002J010)资助项目

INVESTIGATION OF THE PERFORMANCE OF A NEW RECIPE OF SPACER FOR SEA-WATER DRILLING FLUIDS BY MEANS OF LABORATORY AND IN-SITU EXPERIMENTS

前置液是影响固井质量的重要因素之一,对于海水钻井液体系,如何选用前置液是一个新的课题.提出了一种适宜于海水钻井液体系的新型前置液,对其在固井过程中的各种性能进行了室内实验研究,结果表明:新型前置液与海水钻井液、固井水泥浆及盐水等环境流体有良好的相容性,对井壁具有稳定作用,其中的固体颗粒及表面活性剂有利于冲刷海水钻井液形成的泥饼.在此基础上,将新型前置液应用于胜利油田的固井作业,进行现场试验,发现:应用新型前置液后,环空水泥浆界面清晰,混浆段长度缩短,第2界面的胶结质量有明显提高

Knowledge Co-Production Process in Information System Development: A Perspective of Intellectual Capital

引入合作共创这一新概念,基于智力资本的视角,提出了检验ISd用户和开发者之间知识共创性的前因和结果变量实证模型,通过267个开发团队的样本数据证实了知识共创性可促进ISd结果,研究结果表明用户和开发者之间的公共知识、关系资本和参与式决策制定过程促进知识共创的有效性。By systematic reviewing and integrating this theory and intellectual capital perspective into this research design,this paper propose a model to examine the antecedents and consequences of knowledge co-production between ISD users and developers.The empirical results verify the hypotheses that knowledge co-production can benefit ISD outcomes,and common knowledge,relational capital and participative decision-making between these two parties increase the effectiveness of knowledge co-production effectively.华侨大学中央高校基本科研业务费资助项目; 华侨大学哲学社会科学青年学者成长工程资助项目(13SKGC-QG14

SOME PROBLEMS OF FLUID MECHANICS IN WELL CEMENTING IN PETROLEUM ENGINEERING

同井是油气在建过程中的重要工程，一般分下套管和注水泥两个过程．本文结合作者近年来的研究，着重阐述了钻井液、前置液、水泥浆在环形空间中流动的流体力学问题，包括：高温高压下的水泥浆流变性、偏心环形空间中浆液的流动特性、钻井液-前置液和前置液-水泥浆界面的稳定性等，介绍了国内外学者对这些问题的研究进展，提出了今后应深入研究的问题

固井工程中的流动问题

同井是油气在建过程中的重要工程，一般分下套管和注水泥两个过程．本文结合作者近年来的研究，着重阐述了钻井液、前置液、水泥浆在环形空间中流动的流体力学问题，包括：高温高压下的水泥浆流变性、偏心环形空间中浆液的流动特性、钻井液-前置液和前置液-水泥浆界面的稳定性等，介绍了国内外学者对这些问题的研究进展，提出了今后应深入研究的问题

Regional Disparity and Change of Wind Velocities in Wind Erosion Area of Loess Plateau During Last 50 Years

风影响着地面热量平衡和水循环,也是土壤风蚀的主要动力。选取黄土高原风蚀区12个代表站1957—2009年的风速资料,采用距平累积、Mann—Kendall等分析方法,研究了12个站点的平均风速、最大风速变化特征以及起沙日(DTS)的变化规律。结果表明,黄土高原风蚀地区西部和北部地区的固原、盐池县年平均风速最大,东部地区河曲县风速最小,固原、横山和绥德地区的年均起沙日最多。靖远、银川和绥德的年平均风速呈现显著增大趋势,其余站点年平均风速都呈现降低趋势。年最大风速均呈现减小趋势。日最大风速的极大值出现在4—5月,5月份起沙日出现次数最多,由于该时段春耕扰动地表,而且植被萌发前地表覆盖较小,故容易产生风蚀