纳米Zn-Co铁氧体的固相合成及电磁损耗特性研究

采用NH₄HCO₃与FeCl₃·6H₂O，Zn(NO₃)₂·6H₂O，Co(NO₃)₂·6H₂O进行室温固相反应制得前驱物，经微波加热处理后，进而热分解分别制得复合氧化物ZnFe₂O₄、CoFe₂O₄和Co_0.5Zn_0.5Fe₂O₄。由激光粒度分析仪、XRD和SEM表征：获得了颗粒分布比较均一、平均粒度为65 nm左右、立方晶系尖晶石结构的纳米铁氧体粉体。经测试样品的相对介电常数和相对磁导率后，研究了它们的电磁损耗特性。结果表明：Co_0.5Zn_0.5Fe₂O₄在100～1 800 MHz内比另外两种铁氧体具有更好的电磁损耗特性。     

Transfer Hydrogenation of C= C Double Bonds Catalyzed by Ruthenium Amido-Complexes: Scopes, Limitation and Enantioselectivity

The reduction of C = C double bonds is one of the most fundamental synthetic transformations and plays a key role in the manufacturing of a wide variety of bulk and fine chemicals. Hydrogenation of olefinic substrates can be achieved readily with molecular hydrogen in many cases, but transfer hydrogenation methods using suitable donor molecules such as formic acid or alcohols are receiving increasing attention as possible synthetic alternatives because it requires no special equipment and avoids the handling of potentially hazardous gaseous hydrogen.     

过渡金属离子对HPAsMoVO杂多酸的氧化性能的影响

用H2-TPR方法研究了过渡金属离子及其含量对杂多酸-HxPAs0.2Mo10VOy的氧化性能的影响,并在固定床反应器上考察了M0.2HxPAs0.2Mo10VOy(M=Fe3 、Co2 、N i2 和Cu2 )催化剂对异丁烷选择性氧化的催化性能.研究结果表明用过渡金属离子取代杂多酸中的质子,可以在较大程度上增强杂多酸的低温氧化能力,其中Fe3 对增强杂多酸的催化活性最为明显,而Cu2 却有利于提高目的产物甲基丙烯酸的选择性.     

9-羟基-芴-9-羧酸双核铜配合物[Cu(C_(14)H_8O_3)(C_9H_7N)(C_2H_5OH)]_2的合成、晶体结构及热稳定性研究

在自然界中,α-羟基羧酸广泛的存在于动植物体内,在羧酸循环、碳水化合物代谢和氨基酸的合成中起到重要的作用。Tapscott等详细总结了有关羟基羧酸及其金属配合物的合成化学[1]。芴的9位上2个氢原子被羟基和羧基取代可生成9-羟基-芴-9-羧酸(简称芴酸),它是α-羟基乙酸的衍生物,是一种具有生理活性的植物生长整形素,它能够延缓植株生长,影响植株根的向地性和茎的向光性[2]。由于芴酸含有羟基和羧基两种不同的氧配位原子,使其又可以作为一种潜在的构筑配合物的组织基元。目前有关芴酸与金属离子的合成与结构化学研究相对较少,仅见铜、镉的单…     

毛细管电泳-电感耦合等离子体原子发射光谱法对田七提取液中Fe、Cu和Mg存在状态的研究

提出了以水作溶剂微波萃取提取,并以毛细管电泳电感耦合等离子体原子发射光谱(CE-ICP-AES)法测定田七提取液中Mg、Cu和Fe的形态的分析方法。实验结果表明:Mg仅以游离态存在;而Cu和Fe除了游离态以外,还存在其它三种未知的形态。此外,还测定了田七中20个微量元素的总含量,并得到了上述待测元素在水提取液中的提取率。     

黄孢展齿革菌菌丝球同时吸附铅镉离子的动力学

采用间歇法，利用黄孢展齿革菌菌丝球吸附溶液中的Pb^2 和Cd^2 ，研究Pb^2 和Cd^2 共存体系中吸附初速率随初始浓度的变化规律。实验结果表明，少量Cd^2 的存在促进其对Pb^2 的吸附，并提高吸附初速率，但随着Cd^2 初始浓度的增加，促进作用逐渐减弱并转为抑制作用；Cd^2 的吸附初速率随着Pb^2 初始浓度增大而减小；Pb^2 和Cd^2 的吸附初速率都随自身初始浓度的增加而增大。     

Cs-Fe-Co-Bi-Mn-Mo复合氧化物选择性催化氧化异丁烯

Mixed oxide catalyst Cs0.1 Fe2Co6BiMnMo12 Ox was prepared by the interprecipitation method, then the catalyst was calcined at different temperature. Selective oxidation of isobutene was carried out in a fixed-bed reactor. The results showed that the catalyst has high catalytic activity. Under the optimum reaction conditions ( n(-C4^= ) : n(O2) = 1:2-1:4, space velocity = 180h^-1, T = 360℃ ), the yield of methacmlein and methacrylic reached 80%, 8 %,respectively. The total yields of liquid products( methacrolein, methacrylic acid and acetic acid) reached about 90%.     

硝基氢的异构化及分解反应的从头算研究

用从头计算方法对硝基氢（ＨＮＯ２）体系的异构化及分解反应进行了研究，在６－３１Ｇ水平上，该化合物异构化为反式来酸的势垒为２９２ｋＪ／ｍｏｌ，且不易分解为Ｈ＋ＮＯ２或Ｏ＋ＨＮＯ。     

PREPARATION OF POLYSULFONAMIDE/TiO2 NANOCOMPOSITES BY SOL-GEL

Polysulfonamide (PSA) was synthesized at room temperature, the polymerization based on terephthaloyl chloride and 3,3 '-diaminodiphenylsulfone in the common solvent N,N -Dimethyl-acetamide (DMAc). Polysulfonamide/titanium oxide nanocomposites were prepared by sol-gel method. Tetrabutyl titanate(TBT) was added into the polysulfonamide solution, at the same time ,some water was mixed to make the TBT hydrolyze. In the process, hydrochloric acid was used to catalyze the reaction. The polysulfonamide chemistry structure was characterized by FT-IR spectrum. Atomic force microscopy (AFM) was employed to observe the microstructure of the composite film. The thermal property was investigated by TGA.The results show that we have succeeded to synthesize the polysulfonamide, TiO2particles were well distributed in the composite film and average size was about 20 nm on average, the heat-resistance of nanocomposite was batter than the pure polysulfonamide.     

复合生物材料的研究进展

从力学性能的改善和降解速率的可调度等角度,总结了复合生物材料与单一组分的材料相比,在生物医学领域应用中所表现出的综合使用性能的优越性。综述了复合生物材料,特别是用于骨修复的各类有机／无机复合材料近年来的研究进展状况。提出将与人骨中磷灰石微晶类似的羟基磷灰石纳米粒子与可降解聚酯材料进行复合,能够得到具有优越骨诱导性能并且能够降解的新型骨修复材料。这方面的研究代表了有机／无机复合生物材料领域新的发展方向。