Ni-SDC固体氧化物燃料电池阳极的合成和性质

采用柠檬酸-硝酸盐溶胶-凝胶低温自蔓延燃烧法制备氧化镍（NiO）粉末和Ce0.8Sm0.2O1.9（SDC）粉末，并将NiO与SDC按不同质量比和不同制备工艺制备了固体氧化物燃料电池（SOFC）的阳极前身。再用自组装的还原装置将其在820℃经2．5h还原后，采用四端子法测量其电导率值。分析了阳极片电导率与阳极片微结构、Ni的质量百分数、混合研磨时间及烧结温度之间的关系。结果显示，阳极片的电导率强烈依赖于镍含量和制备工艺。     

不同方法掺杂Au对纳米α-Fe2O3气敏性能的影响

分别采用共沉淀法、浸渍法、紫外辐照法制备了掺杂不同Au含量的α-Fe2O3纳米粉体,并制作了旁热式厚膜型气敏元件.用XRD、TG-DTA和TEM技术对纳米晶的晶型、晶粒大小及形貌进行了表征.考察了掺杂方法、Au含量及焙烧温度对α-Fe2O3气敏性能的影响.结果表明,采用三种方法掺杂适量Au后,都使α-Fe2O3的气敏性有了显著提高,其中采用共沉淀法,在400℃焙烧的Au质量分数为1.5%的α-Fe2O3的气敏性最佳.     

新型固液双重致孔球形离子交换剂的制备及其性能研究

以甲基丙烯酸缩水甘油酯为单体 ,采用固液联合致孔方式 ,通过一步悬浮聚合制备了一种新型双孔高分子球形载体 .经化学修饰后 ,得到含二乙胺羟丙基的阴离子交换剂 (介质A) .优化了制备条件 .并与用相同方法制备的但仅含有机溶剂致孔剂的介质B进行了比较 .介质A和B均具有较高的静态吸附容量和机械强度 .由于介质A内含有流动相可以对流通过的大孔 ,因此其动态吸附容量远高于介质B ,并且在较高的流速下表现出较好的色谱流动性能     

集化学家与化学教育家于一身的一代化学大师李比希--纪念李比希诞辰200周年

在德国著名化学家李比希诞辰200周年之际，对这位集化学家与化学教育家于一身的一代化学大师对科学和科学教育以及人类社会作出的贡献进行了评述。     

毛细管离子分析法测定人发中钙和锌

适量人发试样经洗涤、冲洗,并于60℃干燥至恒重后称取1.000 g于600℃灰化后用盐酸(1+1)溶解残渣,溶液定容为100 mL供CIA分析。在10 mmol.L-1咪唑、10 mmol.L-1α-羟基乙酸、pH 4.0的电泳介质中,两离子在10 min内实现了分离。以间接紫外法检测(214 nm),外标法定量。钙(Ⅱ)及锌(Ⅱ)的峰面积与其质量浓度之间在0.5~40 mg.L-1范围内呈线性关系,相关系数分别为0.999 1和0.998 9,检出限(S/N=3)为0.1和0.2 mg.L-1,回收率在97.9%~102.5%之间,相对标准偏差小于2.5%。     

六钨酸四丁基铵盐和异丙醇体系的催化氧化反应的ESR研究Ⅰ.

本文研究了六钨酸四丁基铵盐在紫外光辐照的条件下催化氧化异丙醇为丙酮的反应。采用自旋捕捉技术与电子自旋共振相结合的方法,在位检测到氧化反应过程中有活泼自由基中间体产生,并观察到光电流产生。文中对六钨酸四丁基铵盐的催化反应机理进行了讨论。     

壳聚糖固体聚合物电池用膜

壳聚糖是甲壳素脱乙酰基的产物，具有良好的成膜性、生物相容性、环保以及价格低廉等特点。作为一种碱性高分子膜材料，近年来已成为聚电解质研究领域中的研究热点。本文综述了壳聚糖固体聚合物电池用膜的研究现状，其改性工艺主要包括共混、化学改性、质子酸掺杂、无机盐掺杂等方法，比较了各种工艺处理后壳聚糖固体聚合物电解质膜的性能差异，并就壳聚糖固体聚合物电解质膜中离子传导机理中有待解决的问题进行探讨，并提出了进一步改进壳聚糖固体聚合物电解质膜性能的研究思路。     

A microfluidic device using a green organic light emitting diode as an integrated excitation source

A simply fabricated microfluidic device using a green organic light emitting diode (OLED) and thin film interference filter as integrated excitation source is presented and applied to fluorescence detection of proteins. A layer-by-layer compact system consisting of glass/PDMS microchip, pinhole, excitation filter and OLED is designed and equipped with a coaxial optical fiber and for fluorescence detection a 300 microm thick excitation filter is employed for eliminating nearly 80% of the unwanted light emitted by OLEDs which has overlaped with the fluorescence spectrum of the dyes. The distance between OLED illuminant and microchannels is limited to approximately 1 mm for sensitive detection. The achieved fluorescence signal of 300 microM Rhodamine 6G is about 13 times as high as that without the excitation filter and 3.5 times the result of a perpendicular detection structure. This system has been used for fluorescence detection of Rhodamine 6G, Alexa 532 and BSA conjugates in 4% linear polyacrymide (LPA) buffer (in 1 x TBE, pH 8.3) and 1.4 fmol and 35 fmol mass detection limits at 0.7 nl injection volume for Alexa and Rhodamine dye have been obtained, respectively.     

苯丙氨酸改性树枝状聚赖氨酸的合成及表征

以双芴甲氧羰基赖氨酸(Di- Fmoc -Lysine)为支化单元采用固相多肽合成技术制备了一种树枝状聚赖氨酸.该聚合物表面活性氨基通过与芴甲氧羰基苯丙氨酸(Fmoc- Phe)反应获得表面完全替代的苯丙氨酸改性树枝状聚赖氨酸.产物的分子量和结构经MS和NMR进行了表征.研究结果表明,利用该方法得到的产物分子量单一,是一种潜在的理想非病毒治疗载体.     

Oxidation and Reduction Processes During NO x Removal with Corona-Induced Nonthermal Plasma

In this paper, the NO-to-NO ₂ conversion in various gaseous mixtures is experimentally investigated. Streamer coronas are produced with a dc-superimposed high-frequency ac power supply (10–60 kHz). According to NO _x removal experiments in N ₂ +NO _x and N ₂ +O ₂ +NO _x gaseous mixtures, it is supposed that the reverse reaction NO ₂ +ONO+O ₂ may not only limit NO ₂ production in N ₂ +NO _x mixtures, but also increase the energy cost for NO removal. Oxygen could significantly suppress reduction reactions and enhance oxidation processes. The reduction reactions, such as N+NON ₂ +O, induce negligible NO removal provided the O ₂ concentration is larger than 3.6%. With adding H ₂ O into the reactor, the produced NO ₂ per unit removed NO can be significantly reduced due to NO ₂ oxidation. NH ₃ injection could also significantly decrease the produced NO ₂ via NH and NH ₂ - related reduction reactions. Almost 100% of NO ₂ can be removed in gaseous mixtures of N ₂ +O ₂ +H ₂ O+NO ₂ with negligible NO production.