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31.
Zhu Hai-Liang Huang Pei Duan Chun-Ying Zheng Li-Min Liu Yong-Jiang Wu Mei-Fang Tang Wen-Xia 《Transition Metal Chemistry》1999,24(4):380-383
An azide-bridged polymeric cationic chain complex, [LCu2(N3)2]n(ClO4)2n
·n(H2O)**, where L=the dinucleating macrocyclic ligand bis-p-xylylBISDIEN, has been prepared and characterized by x-ray crystallography, u.v.-vis and i.r. spectra, and by magnetic measurements. The structure consists of cationic azide-bridged [LCu2(N3)2]2+ (unit) chains, non-coordinated perchlorate anions and crystallized water molecules. The azide anion is bound to two copper atoms in neighboring units with an end-to-end bridging mode. In each unit, the copper atoms have a different coordination geometry; Cu(1) is a four-coordinated, distorted square-planar geometry, whereas Cu(2) is a five-coordinated, distorted square-pyramid. The electronic spectra of the title complex differ in anhydrous and in aqueous MeCN solutions, indicating that dissociation and solvation occur in aqueous solutions. The characteristic i.r. absorptions of azides and perchlorates are described. Magnetic moments vary from 2.05 (B.M.) at 300K to2.01 (B.M.) at 80K, which suggests that very weak interactions exist between the metals. 相似文献
32.
微波场中甲烷部分氧化制合成气 Ⅱ.Co/ZrO_2催化剂在微波场中的升温行为及催化活性 总被引:4,自引:0,他引:4
近年来,甲烷部分氧化制合成气(POM)的研究一直十分活跃[1,2].前文报道了用于甲烷部分氧化制合成气的镍基催化剂(Ni/La2O3)在微波场中的升温行为和催化活性[3],发现在达到相同的CH4转化率时,微波活化方式下的催化剂床层温度比常规加热低得多... 相似文献
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在无溶剂绿色化学条件下,将α-萜品烯-马来酸酐加成物(1)与取代苯(硫)脲发生N-酰化反应,合成了4个N-(1-异丙基-2-羧基-4-甲基二环[2.2.2]-5-辛烯-3-羰基)-N′-芳基(硫)脲化合物(3a~3d),并由IR、UV-Vis、MS、1HNMR、13C NMR和元素分析确认了目标产物的结构。生物活性测试表明,其中3个化合物(3a、3b和3c)具有植物激素作用。 相似文献
35.
Rong-Min Wang Zong-Fan Duan Yu-Feng He Zi-Qiang Lei 《Journal of molecular catalysis. A, Chemical》2006,260(1-2):280-287
A new kind of Co–Na heterodinuclear polymer complex based on Salen Schiff base and crown ether has been successfully prepared by condensation polymerization. Its catalytic behavior for aerobic oxidation of cyclohexene, alkylbenzenes and linear aliphatic olefins was studied in the absence of any solvents or reducing agents under mild conditions. The oxidation of cyclohexene catalyzed by the above catalyst proved to be a simple and efficient method for obtaining 2-cyclohexen-1-one (CO) and 2-cyclohexen-ol (OH) in a high selectivity. Kinetics of the oxidation was also investigated. The results showed that the aerobic oxidation of cyclohexene catalyzed by Salen-crown ether heterodinuclear polymer complex follows a radical chain aerobic oxidation mechanism. This oxidation system is also efficient in the oxidation of alkylbenzenes and linear aliphatic olefins, which afforded corresponding benzylic oxidation products and epoxides, respectively. 相似文献
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In this paper, the spectral behavior of protein and Poniacyl Carmine 2B (PC 2B) has been studied by spectrophotometric method. The conditional constants, apparent combination constant K and maximum binding number n, were used to express the combination ability of the reactions between PC 2B and protein under a set of given conditions. The Sandell index s was used to express the sensitivity of the determination of protein. The factors, acidity, PC 2B concentration and the ionic strength, were discussed by the change of apparent combination constant and maximum binding number. It was found that acidity of the solution, PC 2B concentration and ionic strength had a significant effect on the sensitivity of the assay of protein. Under the optimal conditions, the apparent combination constant K and the maximum binding number n were 2.36 × 106 L mol?1 and 95, respectively. With further investigation, it was found that the Scatchard model was suitable in treating the data obtained in the experiments. In the buffer medium of HCl‐KCl at 1.87, the addition of protein made the maximum absorption of the system move from 527 nm to 513 nm. Its apparent molar absorptivity is 4.46 × 105 Lmol?1 cm?1 at 513 nm. Beer's law is obeyed in the range of 0 ? 55 μg mL?1. The system developed in this paper has been used for the determination of protein in milk powder successfully. 相似文献
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硫氰酸根的结构为N≡C-S-,其两端的N原子和S原子分别有一对和三对孤对电子,因此,硫氰酸根可采用多种不同的配位模式与金属离子发生配位。硫氰酸根可作为单齿配体与一个金属离子配位,形成M-SCN或M-NCS的单核配合物,也可以作为桥联配体同时与两个、三个甚至四个金属离子配位形成多核配合物犤1~3犦;另一方面,硫氰酸根是一个具有一定共轭性的偶极子,可传递磁相作用。因此,选择硫氰酸根作为桥联配体,将多个顺磁金属离子桥联形成一维、二维或三维结构的多核金属配合物分子,并研究它们的磁性已成为分子磁学的一个研究领域… 相似文献
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