Synthesis,crystal structure and magnetic properties of a cobalt(II) complex with pyridine-substituted imino nitroxide radicals

The mononuclear Co(im4-py)₄(N₃)₂ complex [im4-py = 2-(p-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl] has been synthesized and structurally characterized. It crystallizes in the triclinic space group Pl¯ with the Co^II ion octahedrally coordinated and bound to four radical ligands through the nitrogen atom of the pyridine rings; the azido groups occupy the apical positions. The complex exhibits weak intramolecular antiferromagnetic interactions between the Co^II ion and the imino nitroxide radicals; intermolecular antiferromagnetic interactions are observed.     

亚铁氰化钛钾从模拟高放废液中去除Cs中试初步研究

本文研究了无机离子交换业铁氰化钛钾对模拟高放废液进行三柱串级的中试实验,结果表明：当模拟高放废液中Ｃｓ的浓度为１．１５ｇ／Ｌ,酸度为１．１ｍｏｌ／Ｌ,焖液流速为２．０ＢＶ／ｈｙ,交换柱穿透率为１％时,干交换剂的交换容量为０．３８ｍｍｏｌ／ｇ,９０％穿透时,交换容量可达０．７７ｍｍｏｌ／ｇ,交换后的废交换剂用０．１ｍｏｌ／Ｌ的硝酸洗涤,卸柱时树脂仍保持良好的球型,说明交换剂亚铁氰化钛钾有良好的机械稳     

Synthesis,Crystal Structure and Spectral Properties of [Fe<Subscript>3</Subscript>(2,2′-bipy)<Subscript>6</Subscript>(ox)<Subscript>3</Subscript>]·12.25H<Subscript>2</Subscript>O Complex

A novel iron (II) complex of formula [Fe₃(2,2′-bipy)₆(ox)₃]·12.25H₂O (2,2′-bipy = 2,2′-bipyridine, ox = oxalate) has been prepared and structurally characterized by X-ray crystallography. In the complex, the metal atoms are six-coordinated in distorted octahedral environment. In the complex [Fe(ox)₃]^4? anions and water molecules are linked together into 1D chain structure by hydrogen interaction. The red crystal of the complex is monoclinic, space group P2₁/c, with a = 22.932(6) Å, b = 13.715(4) Å, c = 22.493(6) Å, β = 93.177(5)°, and V = 7063(3) Å³ with Z = 4.     

用于高能X射线能谱测量的MLS法

为满足高能X射线能谱测量的需要,提出采用MLS法进行能谱测量的方案。MLS法克服了其他测量方法散射不易控制、光场不均匀性影响较大的缺点,还具有对不同角度能谱进行测量的优势。对MLS法的测量原理以及测量过程中的注意事项进行了明确,并利用蒙特卡罗方法针对一特定的X射线能谱设计了两种不同介质的测量装置,并将测量装置自身散射的影响控制在5%以内。     

高温超导SMES磁体的失超检测研究

失超保护是保证磁体安全运行的重要措施,而失超检测是失超保护正常动作的前提。由于SMES磁体运行工况的特殊性,现有失超检测方法在失超信号提取上遇到电磁噪声干扰严重的问题。文中针对高温超导SMES的运行工况,对电桥检测法进行了改进,通过对电桥信号的滤波设计解决电磁噪声干扰,设计了一套适用于高温超导SMES磁体在交变电流情况下的失超检测系统,同时进行了高温超导磁体的失超检测实验。实验结果表明,此系统能快速、准确地检测失超信号,并输出保护动作信号。     

一类多偏差变元的二阶微分方程周期解

本文利用重合度理论研究了一类二阶多偏差变元的微分方程 x＂（t）＋f（t,x（t）,x（t-τ0（t））,x＇（t））＋∑nj=1g（x（t-τj（t）））=p（t） 的周期解问题，得到了存在周期解的新的结果．     

Synthesis and characterization of poly(amide sulfonamide)s (PASAs)

New diamino monomers IIa – IIg were synthesized in a two-step reaction sequence starting from p-acetamidobenzenesulfonyl chloride. Solution polymerization of these monomers in DMAC with terephthaloyl or isophthaloyl chloride resulted in the formation of a series of 14 poly(amide sulfonamide)s (PASAs) in excellent yield (> 95%). The polymers have in-trinsic viscosities of 0.32–1.11 dL g^?1. Except for polymers IIIa ? p and IIId - p , all other PASAs were readily soluble in aprotic polar solvents including DMAC, DMF, and DMSO. Thermogravimetric analyses of the polymers showed moderate thermal stability with 10% weight loss being recorded in the range of 325–408°C. In addition, these polymers exhibit moderate chemical stabilities toward alkali, acidic, and chromic acid solution. © 1995 John Wiley & Sons, Inc.     

The onion-ring structure for Pd-Pt bimetallic clusters

The onion-ring structure is validated in the Pd-Pt bimetallic clusters of total atom numbers 147 and 309 through the Monte Carlo method by using the second-moment approximation of the tight-binding (TB-SMA) potentials, which is conceived in predicting the possible structures of the bimetallic clusters by He et al. [J. Am. Chem. Soc. 2003, 125, 11034] and Hwang et al. [J. Am. Chem. Soc. 2005, 127, 11140]. In the onion-ring structure, Pd atoms and Pt atoms occupy alternate layers of the clusters. The formation of the onion-ring structure can be associated with the fact that the single Pt impurity is favorable to stay in the subsurface layer and the central part of bimetallic clusters.     

Effect of pretreatment on microstructure and photocatalytic activity of kaolinite/TiO<Subscript>2</Subscript> composite

Kaolinite/TiO₂ composites were prepared by using sol-gel method and raw kaolin, pretreated kaolinite and tetrabutyl titanate as the main raw materials. X-ray diffractometer, field-emission scanning electron microscope and infrared spectrometer analysis were carried out to characterize the phase composition and microstructure of the samples. The photocatalytic performance of the kaolinite/TiO₂ composites were evaluated by degrading the methylene blue (MB) and phenol aqueous solution, respectively. The results show that intercalation and exfoliation reduced the size and thickness of kaolinite particles. Acid treatment improved the distribution and the loading quantity of TiO₂ grains. When the kaolinite/TiO₂ composites were calcined at 500?°C, the tetragonal structure of anatase particles of 30–100?nm in size were obtained, but the exfoliated kaolinite crystals were damaged. The degradation rate of MB increased gradually with the extension of photocatalytic reaction time and the enhancement of photocatalyst dosage. The adsorption performance of acid-treated kaolinite/TiO₂ composite (AKT) was nearly the same as that of raw kaolin/TiO₂ composite (RKT), but that of the exfoliated kaolinite/TiO₂ composite (EKT) was the most excellent. The photocatalytic performance of AKT and EKT were better than that of RKT, and AKT exhibited the optimum property. Under a certain photocatalyst dosage and photocatalysis time, the absorption rate and the degradation rate decreased gradually with the enhancement of initial concentration of MB. Similar result was also acquired for the degradation of phenol. Both the acid treating and the exfoliating to kaolinite enhanced the photocatalytic performance of the kaolinite/TiO₂ composite photocatalysts, but acid treatment may be more helpful to the preparation of high performance kaolinite/TiO₂ composite photocatalyst.

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