化学溶液分解法制备(Bi0.9Nd0.1)2Ti2O7薄膜

采用化学溶液分解法（CSD）在p—Si（111）衬底上制备了（Bi0.9Nd0.1）2Ti2o7薄膜。用X射线衍射技术分析了薄膜的结构和结晶性，结果显示，在600℃退火10min得到了结晶性较好、表面致密的多晶薄膜；用原子力显微镜描述了薄膜的表面形貌，与在XRD中观察到的择优取向是一致的；同时还研究了薄膜的电学性能。结果表明，在0～6V范围内，薄膜的漏电流小于1．53×10^10A；在室温100kHz下，其介电常数为166，介电损耗因子为0．227，显示出薄膜具有较好的绝缘性和介电性能。     

Effect of CeO2 preparation method and Cu loading on CuO/CeO2 catalysts for methane combustion

CeO2 was synthesized by sol-gel, hydrothermal, nitrate thermal decomposition methods, respectively, and used as support to prepare CuO/CeO2 catalysts. According to characterization and reaction results, preparation method of CeO2 had a great influence on the physicochemical properties and activities of CuO/CeO2 catalysts. CuO with high dispersion and strong interaction with CeO2 was highly active in methane combustion, while CuO particles less associated with CeO2 showed less activity. The CuO catalyst supported on CeO2 which was prepared via nitrate thermal decomposition method showed the largest area, the smallest particle size, the highest dispersion of copper species and strong support metal interactions. Therefore, it presented the highest redox ability and activity for methane combustion. Activities of the catalysts with different copper content kept increasing until 5% Cu loading and from then on kept constant. Moreover, methane conversion decreased as methane space velocities increased on CuO/CeO2 catalyst. Addition of CO2 to the feed did not produce a significant effect on the catalytic activity, but the presence of H2O provoked a remarkable decrease on the activity of CuO/CeO2 catalyst.     

卟啉-碳纳米管复合物研究进展

碳纳米管是具有一维纳米结构的新型纳米材料,具有许多独特的物理、化学性质.卟啉对可见光具有强烈吸收,其大π共轭体系使其具有良好的电子给予能力,可作为人工光合作用体系的光捕捉单元.将具有电子接受能力的碳纳米管与卟啉结合起来,通过卟啉对碳纳米管进行共价和非共价修饰,可以改善碳纳米管在溶剂中的溶解分散性能,同时实现卟啉和碳纳米管之间有效的电子传递,形成具有独特光电和光学性质卟啉-碳纳米管复合物.该类物质具备良好的应用前景,是碳纳米管和卟啉研究中的热点.就近年来该类复合物的构筑方法及性质研究等方面的进展进行了综述.     

Transport behavior of humic acid-modified nano-hydroxyapatite in saturated packed column: effects of Cu, ionic strength, and ionic composition

The surfaces of nano-hydroxyapatite (nHAP) used for contaminated soil and groundwater remediation may be modified to render nHAP highly mobile in the subsurface. Humic acid (HA) is widely used to modify and stabilize colloid suspensions. In this work, column experiments were conducted to determine the effects of contaminant (e.g., Cu) concentration, ionic strength (IS), and ion composition (IC) on the transport behavior of HA-modified nHAP in saturated packed columns. IS and nature of the cation had strong effects on the deposition of nHAP, and the effect was greater for divalent than for monovalent cations. Divalent cations have a greater capacity to screen the surface charge of nHAP, and Ca(2+) bridges the HA-modified nHAP colloidal particles, which causes greater deposition. Moreover, Cu(2+) had a greater effect on the transport behavior than Ca(2+) due to their strong exchange with Ca(2+) of nHAP and its surface complexation with nHAP. The relative travel distance L(T), of the injected HA-modified nHAP colloids, ranges from less than one to several meters at varying Cu concentrations, ISs, and ICs in saturated packed columns. The results are crucial to evaluate the efficacy of nHAP on the remediation of contaminated soil and groundwater environments.     

潜指纹显现方法研究进展

综合介绍了常用的几种潜指纹显现方法及原理,其中主要综述了指纹的物理化学显现法和化学显现法的进展,包括多金属沉淀法、茚三酮法和荧光材料显现法等。     

Fractional pyrolysis of Cyanobacteria from water blooms over HZSM-5 for high quality bio-oil production

Fractional pyrolysis and one-step pyrolysis of natural algae Cyanobacteria from Taihu Lake were comparatively studied from 200 to 500 ℃. One-step pyrolysis produced bio-oil with complex composition and low high heating value （HHV〈30.9 MJ/kg）. Fractional pyrolysis separated the degradation of different components in Cyanobacteria and improved the selectivity to products in bio-oil. That is, acids at 200 ℃, amides and acids at 300 ℃, phenols and nitriles at 400 ℃, and phenols at 500 ℃, were got as main products, respectively. HZSM-5 could promote the dehydration, cracking and aromatization of pyrolytic intermediates in fractional pyrolysis. At optimal HZSM-5 catalyst dosage of 1.0 g, the selectivity to products and the quality of bio-oil were improved obviously. The main products in bio-oil changed to nitriles （47.2%） at 300 ℃, indoles （51.3%） and phenols （36.3%） at 400 ℃. The oxygen content was reduced to 7.2 wt% and 9.4 wt%, and the HHV was raised to 38.1 and 37.3 MJ/kg at 300 and 400 ℃, respectively. Fractional catalytic pyrolysis was proposed to be an efficient method not only to provide a potential solution for alleviating environmental pressure from water blooms, but also to improve the selectivity to products and obtain high quality bio-oil.     

三维多孔核壳结构PdNi@Au催化剂的制备及对甲酸的电催化氧化

以K₂PdCl₄/K₂Ni(CN)₄为前驱体制备了具有凝胶特性的氰胶(Cyanogels), 利用硼氢化钠还原氰胶得到三维多孔珊瑚状PdNi合金前驱体, 在此基础上通过原位Galvanic置换反应, 制备得到内核为PdNi合金、 表面具有不同厚度Au层的三维多孔PdNi@Au催化剂. X射线衍射(XRD)分析和透射电子显微镜(TEM)观测结果显示, 该三维网状结构由粒径约7 nm的纳米颗粒相互连接形成; 能量分散光谱(EDX)线性扫描和元素分布(Mapping)分析显示该催化剂具有典型的核壳结构. 电化学测试结果表明, 表面Au层的厚度影响PdNi@Au催化剂的性能, 当Au的含量(摩尔分数)为5.6%时, 催化剂显示出对甲酸最佳的电催化活性, 对甲酸电催化氧化的峰电流密度达到商业化铂黑催化剂的7.2倍.     

巯基化合物自组装单分子层的研究进展

超薄层有机材料的制备与研究￣［１］受到人们的广泛关注，有关研究结果和进展正在不断丰富着人类对表面结构与性质关系的理解和认识。与其它制备单分子层的技术相比，自组装技术是一种较新的制备方法，在８０年代后期，迅速成为有关学科的研究焦点。采用此技术制备的超薄层体系主要有两类：一类是巯基化合物在金、银、铜、铂表面吸附形成的单层￣［２，３］，一类是在硅、玻璃、金属氧化物表面通过硅烷化反应形成的单层￣［４］。其中，硫醇类分子自组装单层（ｓｅｌｆ－ａｓｓｅｍｂｌｅｄｍｏｎｏｌａｙｅｒ，３ＡＭ）是被研究得最为广泛和深入的体系。本文主要综述十年来巯基化合物ＳＡＭ的研究进展。     

航天光学遥感器在轨调制传递函数神经网络评价方法

通过对航天光学遥感器在轨调制传递函数模型和遥感图像的分析,找出遥感图像中与调制传递函数有关的特征信息,采用神经网络为工具,完成利用遥感器传输下来的任意一幅地面景物图像进行调制传递函数的评价。首先模拟出包含不同调制传递函数等级的遥感图像,组成训练样本集,再从图像中分别提取出直接与调制传递函数有关的特征参量和与景物结构有关的特征参量,作为神经网络的输入,网络通过对训练样本集中模拟出的大量调制传递函数已知的遥感图像训练后,当再次输入一幅调制传递函数未知的遥感图像时,便能够正确估计出其调制传递函数值。这种方法不需要在地面铺设靶标或预先获得调制传递函数已知的同一地面景物的航空图像作为参考,只需获得任意一幅地面景物图像即可完成对遥感器调制传递函数的评价。实验结果表明,当不考虑噪声对调制传递函数的影响时,对调制传递函数的评价误差约为6%,而在考虑噪声时,评价误差约为9%。     

A Facile and Highly Efficient Approach to Obtain a Fluorescent Chromogenic Porous Organic Polymer for Lymphatic Targeting Imaging

Porous organic polymers have an open architecture, excellent stability, and tunable structural components, revealing great application potential in the field of fluorescence imaging, but this part of the research is still in its infancy. In this study, we aimed to tailor the physical and chemical characteristics of indocyanine green using sulfonic acid groups and conjugated fragments, and prepared amino-grafted porous polymers. The resulting material had excellent solvent and thermal stability, and possessed a relatively large pore structure with a size of 3.4 nm. Based on the synergistic effect of electrostatic bonding and π–π interactions, the fluorescent chromogenic agent, indocyanine green, was tightly incorporated into the pore cavity of POP solids through a one-step immersion method. Accordingly, the fluorescent chromogenic POP demonstrated excellent imaging capabilities in biological experiments. This preparation of fluorescent chromogenic porous organic polymer illustrates a promising application of POP-based solids in both fluorescence imaging and biomedicine applications.