燃烧催化剂中LaAlO3作为第2载体的研究

在载体堇青石表面涂覆一层LaAlO3作为第二载体，用浸渍法制备负载型LaMnO3、LaCoO3等钙钛矿型燃烧催化剂时，发现能促进LaMnO3等活性相的生长，从而提高了二甲苯完全氧化的催化活性；对于负载型LaCo3O3催化剂，可避免因用γ－Al2O35作第二载体而生成的低活性CoAl2O4类尖晶石相，因而有利于提高催化剂的耐热性。     

Chemoenzymatic Synthesis of Cellular Adhesion Tripeptide RGD Precursor in Organic Media

IntroductionA characteristic tripeptide sequence Arg-Gly-Asp(RGD) that is found within fibronectin and other rela-ted adhesion molecules in extracellular matrices(ECM)has received considerable attention from researcherssince it was proved to be a recognit…     

Visual detection of cysteine and homocysteine

The determination of cysteine and homocysteine levels is of great current interest for the monitoring of desease states. A new colorimetric method for the simultaneous detection of l-cysteine and l-homocysteine has been developed. A fluorescein derivative reacts with the above amino acids, producing their respective thiazolidines resulting in color changes. Interference from other amino acids and proteins is minimal.     

Amperometric carbohydrate detection in flow systems by means of a bismuth modified platinum electrode

Bismuth modified platinum electrodes are used for constant-potential amperometric determination of carbohydrates in flow systems. The monitored response is stable and reproducible over more than two days. An attempt is made to gain more detailed information about the characteristics of the modified layer by electrochemical methods and X-ray photoelectron spectroscopy. The response proved to be linear over the investigated concentration range (1.1–1200 mol/L) and detection limits for glucose and fructose were found to be 1.1 mol/L.     

Photovoltaic Characteristics of a Naphthylamine Derivative

Organic photovoltaic （OPV） cells were fabricated via vacuum vapor deposition with {4-[2-（3-di-cyanomethylidene-5,5-dimethylcyclohexenyl）vinyl]phenyl}di（1-naphthyl）amine （DNP-2CN） as the electron donor, and fullerene （C60） as the electron acceptor. A thin film （10 nm） of tris（8-quinolinolato）aluminum （Alq3） was adopted as the buffer layer. A device based on this DNP-2CN exhibited an open circuit voltage （Voc） of 370 mV, a short-circuit current density （Jsc） of 0.61 mAocm 2, and a white-light power conversion efficiency （ η） of 0.09% （AM1.5, 75 mW.cm^- 2）.     

Fe-Co-Ni合金纳米线有序阵列的模板合成与磁性

以二次阳极氧化的氧化铝膜为模板，用电化学沉积的方法成功地合成了Fe-Co-Ni三组份有序纳米线阵列.扫描电子显微镜（SEM）和透射电子显微镜(TEM)观察表明纳米线表面光滑、有序、高长径比；磁性测量表明,其矫顽力较同组份的膜材料有较大的提高.将样品在惰性气体氛围中不同温度下退火，随着退火温度增加，其纵向矫顽力有一个极值，而对应的横向矫顽力没有类似的变化，关于这一现象的机理,本文进行了初步的讨论. 图5参15     

Multicomponent coupling reactions for organic synthesis: chemoselective reactions with amide-aldehyde mixtures

The acid-catalyzed condensation chemistry of simple amides and aldehydes provides a highly prolific source of diverse reactants for irreversible follow-up reactions. Amide-aldehyde mixtures have been successfully employed in multicomponent syntheses of N-acyl alpha-amino acids (via palladium-catalyzed amidocarbonylation) and various cyclohexene, cyclohexadiene, and benzene derivatives (via the amide-aldehyde-dienophile (AAD) reaction).     

醋酸乙烯酯-马来酸酐共聚物与水解聚丙烯酰胺高分子络合物的研究

<正> 某些高分子在溶液中可以通过次价力形成高分子络合物.根据次价力的不同,可分为四类:聚电解质络合物、氢键络合物、立体络合物和电荷转移络合物.部分水解聚丙烯酰胺(简称HPAM)是在水悬浮体中被广泛使用的絮凝剂,醋酸乙烯酯-马来酸酐共聚物(简称VAMA)是一种能力很强的泥浆稀释剂.研究二者在水溶液中的相互作用,在理论上和应用上都有重要意义.我们曾研究了粘土对它们的吸附作用、改变泥浆流变性以     

固相微萃取参数选择及其对有机锡分析的影响

固相微萃取是一种新型的、不断发展和完善的样品前处理方法，它与其它技术联用可对多种样品基体中挥发、半挥发性有机化合物进行测定。目前，该技术在毒性金属有机化合物中的应用很少。本文分析参数选择对固相微萃取的影响的同时，还对其在有机锡化合物分析中的应用作了综述。     

含聚醚间隔链的扩链脲改性环氧树脂/双氰双胺固化体系性能研究

合成了一系列含不同分子量聚环氧丙烷 (PPG)柔性间隔链的扩链脲 ,系统考察了扩链脲改性环氧树脂E 5 1/双氰双胺 (dicy)固化体系的固化反应活性、动态力学行为、冲击性能和断裂面形态结构 ,并对体系的冲击性能、形态结构与动态力学行为之间的关系进行了探讨 .结果表明 ,改性体系固化反应活性明显提高 ,固化反应表观活化能降低 ,固化反应峰顶温度从 190℃降低至 14 0℃ ,固化反应的表观活化能由 14 5 5kJ/mol降至 70～ 80kJ mol;改性体系冲击强度明显提高 ,其中所含PPG柔性链分子量为 10 0 0的扩链脲改性的E 5 1/dicy体系冲击强度较未改性的E 5 1/dicy体系提高了 8倍 ,其冲击试样断裂面的形态具有明显的韧性断裂特征 ,微观两相网络结构的存在导致了改性体系冲击强度显著提高