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141.
《Journal of Coordination Chemistry》2012,65(12):2160-2170
Two pentagonal bipyramidal complexes, ethanol-(S-ethyl-N1,N4-bis(3-methoxy-2-hydroxybenzaldehyde)-isothiosemicarbazide-N,N′,O,O′)-dioxidouranium(VI) (1) and ethanol-(S-ethyl-N1-(2-hydroxyacetophenone)-N4-(5-bromo-2-hydroxybenzaldehyde)-isothiosemicarbazide-N,N′,O,O′)-dioxidouranium(VI) (2), have been prepared and characterized. Their structures have been determined by X-ray crystallography, and the structural parameters are discussed with those observed in related complexes. Electronic absorption, proton magnetic resonance, and FT-IR spectra have been recorded and analyzed. In both complexes, the U(VI) centers are surrounded by N2O2 donor ligands, two oxido groups, and one ethanol in a distorted pentagonal bipyramid. The thermal stability of the new complexes has also been determined. 相似文献
142.
《Journal of Coordination Chemistry》2012,65(21):2335-2342
The ruthenium tricarbonyl derivative [Ru(CO)3(sha)] (1), was synthesized from reaction of [Ru3(CO)12] with N-salicylidene-2-hydroxyaniline (shaH2) Schiff base. The corresponding reactions of the ruthenium cluster with shaH2 in presence of a secondary ligand L,L?=?pyridine and triphenyl phosphine resulted in the formation of the dicarbonyl derivatives [Ru(CO)2(shaH2)(L)] (2, 3). In the presence of L?=?2-aminobenzimidazole or thiourea, two complexes [Ru(CO)2(sha)(L)] (4, 5) were formed and the shaH2 ligand bonded to ruthenium oxidatively. The bipyridine(bpy) derivative had the molecular formula [Ru(CO)2(shaH)(bpy)] (6), with shaH coordinated bidentate. All complexes were characterized by elemental analysis and mass, IR, 1H NMR and UV–Vis spectroscopy. The spectroscopic studies of these complexes revealed several structural arrangements and different tautomeric forms. 相似文献
143.
144.
《Journal of Coordination Chemistry》2012,65(5):868-883
The reaction of copper(II) salts with (E)-N-(2-hydroxy-1,2-di(pyridin-2-yl)ethylidene)aroyl hydrazide (H2L1, H2L2, H3L3) or (E)-N-(2-hydroxy-1,2-di(pyridin-2-yl)ethylidene) isonicotinohydrazide (H2L4) afforded the complexes [(L)Cu(H2O)3], [(H2L)Cu(OAc)(H2O)], [(HL)Cu(OAc)] n , [(H2L)Cu(H2O)](ClO4)2 and [(H2L)Cu(OAc)(H2O)], where n = 1 or 2 and L is the dinegative ion of the ligands. The ligands and their complexes are characterized by elemental analyses, spectral (IR, NMR, electronic, and ESR) and magnetic studies. The FT-IR indicates that the ligands are neutral or anionic polydentate. The number of the coordinating centers depends on the nature of the metal used and the reaction conditions. The room temperature magnetic moment values, electronic spectra and ESR data indicate square planar, trigonal bipyramidal, square pyramidal, and distorted octahedral ligand fields around copper(II). Thermal decomposition of the complexes was monitored by TG and DTG under N2 and the thermal decomposition mechanisms are given. The compounds were screened for their antimicrobial activities on some Gram-positive and Gram-negative bacterial species. The free ligands are inactive against all studied bacteria. The complexes have variable activity with the most active [(H2L)Cu(H2O)](ClO4)2, where H2L is H2L1 or H2L2. The minimum inhibition concentrations for these two complexes were determined. These biological activity results are related to the structures of the compounds. 相似文献
145.
《Journal of Coordination Chemistry》2012,65(20):3519-3529
A mesogenic Schiff-base, N,N′-di-(4-decyloxysalicylidene)-1′,3′-diaminobenzene, H2ddsdbz (abbreviated as H2L), that exhibits a nematic mesophase was synthesized and its structure was studied by elemental analysis, mass spectrometry, NMR, and IR spectral techniques. The Schiff-base, H2L, upon condensation with hydrated lanthanide(III) nitrates yields LnIII complexes, [Ln2(LH2)3(NO3)4](NO3)2, where Ln?=?La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, and Ho. Analyses of the IR and NMR spectral data imply bidentate Schiff-base through two phenolate oxygen atoms in its zwitterionic form to LnIII, rendering the overall geometry of the complexes as a seven-coordinate polyhedron – possibly distorted mono-capped octahedron. Polarizing optical microscope and differential scanning calorimetry studies reveal that despite H2L being mesogenic, none of the LnIII complexes synthesized under this study exhibits mesomorphism. 相似文献
146.
《Journal of Coordination Chemistry》2012,65(10):1553-1567
Synthetic procedures are described that allow access to cis-[Mo2O5(cdhp)2]2?, cis-[W2O5(Hcdhp)2], trans-[OsO2(cdhp)2]2?, trans-[UO2(Hcdhp)2], [ReO(PPh3)(Hcdhp)2]X (X =?Cl, I), [ReO2(cdhp)2]?, [M(PPh3)2(cdhp)], [M(bpy)(cdhp)] (M(II) =?Pd, Pt), [Ru(YPh3)2(Hcdhp)2] (Y =?P, As), [Rh(Hcdhp)2Cl(H2O)], [Rh(PPh3)2(Hcdhp)2]ClO4 and [Ir(bpy)(cdhp)Cl2], where Hcdhp, cdhp are the deprotonated monoanion of 5-chloro-3-hydroxypyrid-2-one and dianion of 5-chloro-2,3-dihydroxypyridine, respectively. These complexes were characterized by their Raman, IR, 1H NMR, electronic and mass spectra, conductivity, magnetic and thermal measurements. H2cdhp, cis-K2[Mo2O5(cdhp)2], [Pd(bpy)(cdhp)] display a significant antineoplastic activity against Ehrlich ascites tumor cells (EAC). 相似文献
147.
《Journal of Coordination Chemistry》2012,65(16):1375-1381
Interaction of bis-(salicylaldehyde)ethylenediimine, salenH2, with M(CO)6 (M = Cr, Mo) in air gave M(O)(salen) complexes. Magnetic studies show that the metal exists in the +4 oxidation state. Cr(CO)6 reacted with salenH2 under reduced pressure to yield the dicarbonyl derivative Cr(CO)2(salenH2). Reactions of M(CO)6 with salenH2 in the presence of a secondary ligand L (L = H2O, pyridine) resulted in the formation of the square pyramidal complex M(L)(salenH2). UV-Vis spectra of the complexes exhibited visible bands due to metal-to-ligand charge transfer. Structures for the complexes are proposed on the basis of spectroscopic studies. 相似文献
148.
149.
在采用最优线性联想记忆(Optimal Linear Associative Memory)神经网络分析X荧光谱时,可用多种方式对谱作预处理,如去掉多余数据、取对数、横向压缩、标准化等.针对实验测得的水泥生料X荧光谱,分别用上述方法进行预处理,然后再用神经网络分析,与化学分析的偏差作对比.结果表明,去掉多余数据、横向压缩可以减少信息处理量,减少存储空间,提高运算速度,且对精度影响较小;标准化处理对含量较少的成分有优势,对含量大的成分误差太大;对数方法则不适用. 相似文献
150.
丙三醇溶液声致发光中的黑体辐射谱 总被引:1,自引:0,他引:1
利用U型管圆锥泡声致发光装置,测量到了丙三醇溶液中圆锥泡声致发光的光谱和光脉冲。结果表明,测量得到的发光光谱为光滑的连续谱,且与理论模拟得到的黑体辐射谱相吻合,拟合温度分布于2 600~3 500 K范围内。文章从空间和时间两方面分析了圆锥泡空化发光中存在黑体辐射的原因:较大的气泡体积(气泡塌缩半径为1.4 cm)与较长的发光时间(几十微秒)。另外,实验研究表明随着发光波长的增长,光脉冲宽度变宽,从而进一步证明了圆锥泡声致发光中的黑体辐射机制。最后,利用测量得到的发光光谱和脉冲计算得到了发光光强为0.18 J,远远高于其他方式得到的声致发光光强。 相似文献