Ionic liquid as reaction medium for the synthesis and crystallization of a metal-organic framework: (BMIM)2[Cd3(BDC)3Br2] (BMIM = 1-butyl-3-methylimidazolium, BDC = 1,4-benzenedicarboxylate)

An ionic liquid, 1-butyl-3-methylimidazolium bromide, is used as reaction medium for the synthesis and crystallization of a coordination polymer, (BMIM)₂[Cd₃(BDC)₃Br ₂] (1) (BMIM = 1-butyl-3-methylimidazolium, BDC =  1,4-benzenedicarboxylate), which forms an anionic two-dimensional framework with the imidazolium cations located between the layers. This compound is thermally stable up to ca. 340 °C and exhibits blue emission in solid state at room temperature. Other characterizations by IR and UV–visible spectra are also described.     

降维方法监督分类的比较研究

对ISOMap、LDA、LLE、PCA这4种典型降维算法的主要思想和算法步骤进行了详细分析,并将它们用于有监督分类。从实验结果分析得到结论 ,其可为有监督分类提供有益的借鉴。     

锐钛型TiO2对尿素热解过程的影响

通过实验的方法收集了不同温度下纯尿素和尿素/TiO₂混合物热解后的固体残留物，使用红外光谱（IR）及气相色谱质谱联机（GC-MS）方法对这些热解残留物进行成分分析；使用热重-红外联机（TG-FTIR）技术研究尿素及三聚氰酸在有无催化剂TiO₂的情况下的热解特性及气体产物的生成规律；根据Coats-Renfern方法对尿素热解第一阶段的非等温热失重率曲线的数据进行动力学研究，建立动力学方程。结果表明，100~250℃的尿素热解残留物中主要为尿素和缩二脲，300~400℃的尿素热解残留物中主要为三聚氰酸等含氮杂环有机化合物；锐钛型TiO₂能促进尿素和三聚氰酸的热解反应，缩短其反应进程，HNCO与水蒸气在TiO₂表面易发生反应；尿素第一阶段热解的反应级数为2，单独热解时活化能为113.25kJ/mol，指前因子A为2.01×10¹¹min^-1，在催化剂TiO₂的作用下，活化能E为77.42kJ/mol，指前因子A为4.82×10⁷min^-1。     

Synergic effect of Pd/γ-alumina and Cu/ZSM-5 on the performance of NO x storage reduction catalyst

NO _x reduction with a combination of catalysts, Pd catalyst, NO _x storage reduction (NSR) catalyst and Cu/ZSM-5 in turn, was investigated to elucidate for the high NO _x reduction activity of this catalyst combination under oxidative atmosphere with periodic deep rich operation. The catalytic activity was evaluated using the simulated exhaust gases with periodically fluctuation between oxidative and reductive atmospheres, and it was found that the NO _x reduction activity with this catalyst combination was apparently higher than that of the solely accumulation of these individual activities, which was caused by the additional synergic effect by this combination. The Pd catalyst upstream of the NSR catalyst improved NO _x storage ability by NO₂ formation under oxidative atmosphere. The stored NO _x was reduced to NH₃ on the NSR catalyst, and the generated NH₃ was adsorbed on Cu/ZSM-5 downstream of the NSR catalyst under the reductive atmosphere, and subsequently reacted with NO _x on the Cu/ZSM-5 under the oxidative atmosphere.     

基于幂图的属性约简

针对粗糙集理论中基于差别矩阵的属性约简方法存在的不足,提出一种基于幂图的属性约简算法.首先通过修改样本决策属性值将不相容决策表转化为简化的相容决策表;然后将样本对概念与幂图概念相结合,将基于修正差别矩阵的不相容决策表的属性约简转化为幂图的搜索问题;最后通过实例和实验验证了所提出算法的有效性.     

基于容差关系的不完备信息系统的属性约简

粗糙集理论是一种处理不确定性知识的有效工具,属性约简是其核心内容之一,然而对于属性值有缺省的不完备信息系统,基于等价关系的经典粗糙集理论已经不再适用。由于容差关系下的不完备信息系统的属性约简的定义与经典粗糙集的属性约简定义相似,可以用容差关系对粗糙集理论进行扩充。文中通过定义容差关系下的可辨识矩阵,运用可辨识方法,得到了一种属性约简算法;接着分析了算法的不足之处,并且在此基础上提出了增加约简效率的改进型算法;最后通过一个数值例子,说明了该算法是合理的和有效的。     

双边剪智能剪切控制功能的研发与应用

在宽厚板项目中,双边剪用来剪切钢板两个纵边,以达到厂家要求的钢板宽度。本文除了介绍宽厚板双边剪的系统配置及功能特点外,主要阐述智能剪切的自动控制。本着降本增效的原则,开发一种新的主传动控制模式,优化双边剪电机剪切程序,在钢板厚度满足设定条件的前提下,固定侧与移动侧各采用一组电机驱动剪刃,并且实现主从电机智能激活切换模式,以满足生产需要。经实践证明,优化后的控制系统不仅提高了生产效率,还实现了节能降耗、安全生产的目的。     

烯唑醇的合成研究

选用氯甲特丁酮与1H－1，2，4－三唑反应，生成物再与2，4－二氯苯甲醛反应，生成Z－酮衍生物，经异构化，还原反应，即得烯唑醇（E体）。     

竹红菌甲素衍生物13－SO_3Na－DDHA电化学及光诱导还原的研究

本工作研究了化合物１３－ＳＯ＿３Ｎａ－ＤＤＨＡ在不同ｐＨ的缓冲溶液中的电化学氧化还原行为．实验证明：化合物中羰基的还原电位与ｐＨ之间存在线性关系，其直线的斜率为６０ｍＶ／ｐＨ．并证明了此过程为一步两电子、两质子还原过程：Ｑ＋２Ｈ￣＋＋２ｅ＝ＱＨ＿２．ＤＭＦ作为非质子溶剂，具有很好的稳定自由基的作用．向缓冲溶液中加入ＤＭＦ后，化合物１３－ＳＯ＿３Ｎａ－ＤＤＨＡ为两步单电子还原过程，相应溶液中的光诱导电子转移吸收光谱证实了以上电化学的结果．     

Exploring single electrode reactions in polymer electrolyte fuel cells

Utilising a pseudo-reference electrode in polymer electrolyte fuel cells allows for the separation of anodic and cathodic contributions to the entire cell impedance. Modelling the impedance responses by using equivalent circuits inhibits the investigation of kinetic parameters of the basic electrochemical reactions, which take place at single electrode-electrolyte interfaces. Therefore, we evaluate single electrode impedance measurements by a kinetic model, which is based on specific reaction pathways, either for the oxygen reduction reaction (ORR) or the hydrogen oxidation reaction (HOR). As a consequence, it is possible to obtain kinetic parameters for the specific reaction of interest. Furthermore, the information gained from the single electrode impedance measurements and the kinetic model can give insight into single reactions steps. In particular, the ORR has to include a chemical step in the reaction pathway.