界面聚合法合成聚邻苯二胺及其表征

邻苯二胺电聚合膜己广泛用于生物活性物质固定、电催化、腐蚀防护和电色材料研究,近期也用于制备分子印迹型化学/生物传感器[1,2]。人们已经研究了聚邻苯二胺的结构特性、性能及应用前景[3,4,5]。目前聚合物基纳米复合材料的制备方法主要有:分子自组装法、微乳液聚合法、电化学     

噻吩基和呋喃基取代的1,2,3-硒二唑衍生物的合成

提供了一种合成噻吩基和呋喃基取代的衍生物的方法,并用其合成方法合成了四种未见文献报道的化合物,测定了四种化合物的红外光谱,核磁共振及元素分析值。     

Molecular Vibrations of an Oxygen-Evolving Complex and Its Synthetic Mimic

Bio-inspired catalysis for artificial photosynthesis has been widely studied for decades, in particular, with the purpose of using bio-disposable and non-toxic metals as building blocks. The characterisation of such catalysts has been achieved by using different kinds of spectroscopic methods, from X-ray crystallography to NMR spectroscopy. An artificial Mn₄CaO₄ cubane cluster with dangling Mn₄ was synthesised in 2015 [Zhang et al. Science 2015 , 348, 690–693]; this cluster showed many structural similarities to that of the natural oxygen-evolving complex. An accurate structural and spectroscopic comparison between the natural and artificial systems is highly relevant to understand the catalytic mechanism. Among data from different techniques, the differential FTIR spectra (S_n+1−S_n) of photosystem II are still lacking a complete interpretation. The availability of IR data of the artificial cluster offers a unique opportunity to assign absolute absorption spectra on a well-defined and easier to interpret analogous moiety. The present work aims to investigate the novel inorganic compound as a model system for an oxygen-evolving complex through measurement of its spectroscopic properties. The experimental results are compared with calculations by using a variety of theoretical methods (normal mode analysis, effective normal mode analysis) in the S₁ state. We underline the similarities and the differences in the computational spectra based on atomistic models of Mn₄CaO₅ and Mn₄CaO₄ complexes.     

Influence of hydrothermal conditions on the phase transformations of amorphous alumina

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乙醇在Ni-ZnO-ZrO_2-YSZ阳极SOFC上的发电性能

为考察乙醇用于固体氧化物燃料电池的可行性,用柠檬酸溶胶-凝胶制备阳极催化材料Ni-ZnO-ZrO2,利用机械混合法制备Ni-ZnO-ZrO2-YSZ(Y2O3稳定的ZrO2)阳极。用涂覆法,在YSZ电解质上,制备了Ni-ZnO-ZrO2-YSZ/YSZ/LSM(La0.85Sr0.15MnO3)与Ni-YSZ/YSZ/LSM的单体电池。在不同蒸发器操作温度、电池操作温度和乙醇蒸气流量下,以乙醇为燃料进行发电实验,对两种阳极的电池发电性能进行比较。实验结束后,用SEM检测了两种电池阳极的表面。结果表明,Ni-ZnO-ZrO2-YSZ阳极SOFC的电池输出性能明显高于Ni-YSZ阳极,且Ni-ZnO-ZrO2-YSZ阳极具有较好的抗积炭能力。     

乙醇在Ni-ZnO-ZrO2-YSZ阳极SOFC上的发电性能

为考察乙醇用于固体氧化物燃料电池的可行性,用柠檬酸溶胶 凝胶制备阳极催化材料Ni-ZnO-ZrO₂,利用机械混合法制备Ni-ZnO-ZrO₂-YSZ(Y₂O₃稳定的ZrO₂)阳极。用涂覆法,在YSZ电解质上,制备了Ni-ZnO-ZrO₂-YSZ/YSZ/LSM（La_0.85Sr_0.15MnO₃）与Ni-YSZ/YSZ/LSM的单体电池。在不同蒸发器操作温度、电池操作温度和乙醇蒸气流量下,以乙醇为燃料进行发电实验,对两种阳极的电池发电性能进行比较。实验结束后,用SEM检测了两种电池阳极的表面。结果表明,Ni-ZnO-ZrO₂-YSZ阳极SOFC的电池输出性能明显高于Ni-YSZ阳极,且Ni-ZnO-ZrO₂-YSZ阳极具有较好的抗积炭能力。     

湿法消解-火焰原子吸收光谱法测定黑种草籽中的4种金属元素

黑种草籽经湿法消解,用火焰原子吸收光谱法测定Cu、Fe、Mn、Zn的含量。该方法快速、简便、准确,4种金属的回收率为97.85%—101.95%,RSD为0.68%—2.08%,结果表明,黑种草籽中铁、锌元素含量较高。     

一种新的双正交小波的构造方法研究

在二进提升方案相关理论的基础上,结合双正交性、消失矩性和对称性条件,提出一种构造提升双正交小波的新方法.此方法从二进小波出发,考虑小波所具有的特性,通过选取适当的提升参数,具体构造了具有紧支撑、对称性、高阶消失矩和速降性的提升双正交小波.     

稳定的和不稳定的稳态轨迹

研究了一个特殊自治系统稳态轨迹的稳定性,并用延拓法给出了结果的证明·     

考虑到渗透效应的一种血液流动的计算方法

得到了定常情况下,狗二分叉动脉横截面的三维Navier＿Stokes方程的有限元处理方法,并考虑到管壁的渗透影响,数值方法还包括直角坐标和曲线坐标的变换·　详细讨论了渗透性影响下的定常流、分叉流以及切应力情况·　以分支和主干血管的速度比为参量,计算雷诺数为1000情况下管壁切应力,数值结果和先前的实验结果符合得很好·　该文的工作是Sharma等(2001)工作的改进,使计算量更小,能够处理的雷诺数范围更大·