CO+H2O液相光反应的Pt/TiO2催化剂表面性质的研究

发现了高温氢后处理能有效地改变Pt/TiO_2的表面性质,明显地提高了它对CO+H_2O液相光反应的性能。为此,用动电位扫描法研究了Pt/TiO_2表面性质的变化对固-液界面电荷传递过程的影响。结果表明,经高温氢处理后所产生的Pt—TiO_2之间的强相互作用引起了Pt-TiO_2接触特性和Pt/Ti0_2催化剂表面性质的改变,从而加速了固-液界面电荷传递过程,提高了Pt/TiO_2对CO+H_2O液相光反应的性能。还观察到Pt/TiO_2表面性质的改变可导致CO和Pt/TiO_2光电极之间电荷的直接交换。     

甲烷部分氧化制甲醛催化剂MoO_3／SiO_2及MoO-3·MxOy／SiO_2的程序升温还原研究

利用程序升温还原（ＴＰＲ）方法，研究了甲烷部分氧化制甲醛催化剂ＭｏＯ３／ＳｉＯ２及添加金属氧化物的ＭｏＯ３·ＭｘＯｙ／ＳｉＯ２（Ｍ＝Ｖ、Ｆｅ、Ｎｉ、Ｃｒ、Ｃｕ）催化剂上，活性组分在载体上的分散及ＭｏＯ３与ＭｘＯｙ的相互作用．发现钼含量的提高不利于ＭｏＯ３在ＳｉＯ２上的分散，催化剂表面晶相ＭｏＯ３随钼含量的提高而增多．ＳｉＯ２上担载的活性组分有一个最佳值，对应于最佳催化活性．ＭｏＯ３·ＭｘＯｙ／ＳｉＯ２催化剂中ＭｏＯ３与ＭｘＯｙ发生了不同的相互作用，影响催化剂表面的活性氧物种，导致它们对甲烷氧化活性和甲醛选择性的不同．ＭｏＯ３·Ｖ２Ｏ５／ＳｉＯ２是比较好的催化剂，且Ｖ２Ｏ５添加量有最佳值，对应甲烷氧化制甲醛也有较高的活性和选择性．     

STRUCTURE-PROPERTY RELATIONSHIP OF POLYELECTROLYTES AND ITS APPLICATION IN STABILIZING DRILLING-MUD IN PRESENCE OF SALTS

A new polyelectrolyte (SPU) has been prepared. It can depress the water-loss of drilling-mud much more effective than the commonly used acrylic polyelectrolytes even in 30% NaCl solution. SPU has phenyl group in the backbone with -SO_3~- in the side chain while the acrylic polyelectrolytes have C—C and -COO~- respectively, there exists an intrinsic relationship between the structure of polymer and its tolerance to salts, it has been found: 1) The adsorption amount of polymer on clay is related closely to the flexibility of polymer chain. 2) The salt-tolerance of -SO_3~- is superior to -COO-. 3) Both SPU-mud and HPAN-mud are plastic fluids. The dependence of yield point on salts relates to the molecular weight of polymer and hydration of ionogenic group, which is quite different for SPU-mud and HPAN-mud. 4 ) The extent of raising zeta-potential of base-mud by SPU is greater than by HPAN, but the extent of dropping zeta-potential of SPU-mud by NaCI is smaller than HPAN-mud. According to these results we suppose the salt-tolerance of SPU-mud is attributed mainly to hydration of -SO_3~- and that of HPAN-mud mainly to network structure formed in the drilling-mud.     

光学适配体传感器检测赭曲霉毒素A的应用进展

赭曲霉毒素A(OTA)是由曲霉和青霉产生的一种真菌毒素,具有强烈的肝肾毒性,并有致畸、致癌的危害。OTA广泛存在于如小麦、玉米、咖啡、葡萄等谷物及食品中,严重危害人类健康。鉴于其危害的严重性和分布的广泛性,发展方便快捷、高灵敏度的OTA检测技术具有重要意义。目前检测OTA的方法有薄层色谱法、高效液相色谱法、荧光分析法及酶联免疫吸附测定法等,这些方法通常成本高、操作复杂且费时。光学适配体传感器发展迅速,在OTA检测领域表现出巨大优势,因此综述了荧光型（包括标记型和免标记型）、比色型、化学发光型以及其他类型（表面等离子体共振、侧向层析、表面增强拉曼散射型）光学适配体传感器检测OTA的原理、性能及在2011-2023年间的相关应用,并对方法面临的问题进行了总结以及未来的的发展趋势进行了展望（引用文献81篇）。     

锌的添加方式对氢氧化镍结构和性能的影响

研究了以共沉淀、包覆、机械混合等不同方式添加或不添加锌对微乳液法合成的氢氧化镍结构和性质的影响。XRD、循环伏安和恒电流充放电测试结果表明：微乳液法的合成物仍是具有六方晶体结构的B-Ni(0H)2,但其晶粒度很小,且化学计量比不等于1／2,所以材料的活性和放电比容量下降;锌的添加增加了Ni(OH)2的晶体缺陷,改善了Ni(OH)2的结构,增加了电极中电子和质子的传递能力,从而提高了氢氧化镍电极的可逆性,强化了电极的析氧极化,其充电效率和放电比容量也随之提高;其中,以共沉淀方式添加锌,氢氧化镍电极的性能最好。     

求复折射率波导本征值的打靶法

给出了求一维缓变复折射率波导本征值的打靶法，它是对求一维实折射率波导本征值的打靶法的推广，利用它可以分析增益或损耗对ＴＥ和ＴＭ模式的影响，并给出了计算实例。     

峰蜜中杀虫脒的快速测定法

 建立了测定峰蜜中杀虫脒的薄层色谱法,不需要大型仪器和特殊试剂,不受基体干扰,整个测定过程仅需３ｈ,回收率在７０％以上,能满足蜂蜜生产和加工现场检验工作需要。     

Ni基催化剂上甲烷与空气或O_2/水蒸气部分氧化制合成气(英文)

在固定床反应器中考察了Ni基催化剂上甲烷氧化与空气或O2/水蒸气部分氧化制合成气的反应。用空气取代纯氧同样能获得高甲烷转化率和产物选择性。水的添加主要发生水气变换反应,同时也能降低催化剂上积炭。在甲烷与纯氧500小时反应的稳定性考察中,甲烷转化率、CO及H2选择性分别保持在90％、95％和95％以上;反应后上层催化剂的Ni含量从新鲜催化剂的7.2％下降到5.2％,在反应后的催化剂上没有发现积炭和相变。     

A method of recovering the initial vectors of globally coupled map lattices based on symbolic dynamics

Based on symbolic dynamics, a novel computationally efficient algorithm is proposed to estimate the unknown initial vectors of globally coupled map lattices (CMLs). It is proved that not all inverse chaotic mapping functions are satisfied for contraction mapping. It is found that the values in phase space do not always converge on their initial values with respect to sufficient backward iteration of the symbolic vectors in terms of global convergence or divergence (CD). Both CD property and the coupling strength are directly related to the mapping function of the existing CML. Furthermore, the CD properties of Logistic, Bernoulli, and Tent chaotic mapping functions are investigated and compared. Various simulation results and the performances of the initial vector estimation with different signal-to-noise ratios (SNRs) are also provided to confirm the proposed algorithm. Finally, based on the spatiotemporal chaotic characteristics of the CML, the conditions of estimating the initial vectors using symbolic dynamics are discussed. The presented method provides both theoretical and experimental results for better understanding and characterizing the behaviours of spatiotemporal chaotic systems.