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Summary Bidentate bridging base polymer complexes of acetylacetonatoiron(II) [Fe(acac)2L]n, where L=pyrazine(pyz), 4,4-bipyridine(bpy),trans-1,2-bis(4-pyridyl)ethylene(bpe), 1,2-bis(4-pyridyl)ethane(bpa) and 4,4-trimethylene bipyridine(tmbpy), have been prepared, characterized and oxidized by iodine to give a range of iron(III) and iron(II) complexes [Fe(acac)2L · Ix]n] in which the FeIII/FeII ratios were established by Mössbauer spectroscopy. The electric conductivities of compressed pellets of the polysalts were obtained. The conductivities and Mössbauer parameters (I.S. and Q.S.) both change with respect to the kind of bidentate bridging bases.The conjugation of bridged ligand markedly affects the conductivity of the complexes. 相似文献
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Kai-Ming Chi Hung-Chang Houa Kuo-Hsien Chen Shin-Guang Shyu Yuh-Sheng Wen 《中国化学会会志》1995,42(3):547-554
Copper(I) complexes of general formula (β-diketonate)Cu(7-AcO-NBD), where 7-AcO-NBD = 7-norbornadienyl acetate and β-diketonate = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate (1), 1,1,1-trifluoro-2,4-pentanedionate (2), 2,4-pentanedionate (3), 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionate (4), 4,4,4-trifluoro-1-phenyl-1,3-butanedionate (5), were prepared from reactions of CuCl with Na(β-diketonate) in the presence of 7-AcO-NBD. AH compounds were characterized by elemental analyses, 1H, 13C, 19F NMR and IR spectra. Single-crystal strucutre of compound 1 was determined by X-ray diffraction analysis that showed a mononuclear copper species with coordination of a chelating β-diketonate ligand through two oxygen atoms and the 7-AcO-NBD through its C? C double bond and an oxygen atom in the solid state. For compound 1, the crystal data are: triclinic, space group $ {\rm P}\bar 1 $, a= 5.4519(14) Å, b= 11.852(3) Å, c= 13.304(3) Å, α = 74.721(20)° β = 80.220(20)°, γ= 76.848(19)°, Z = 2, RF = 0.060 and Rw = 0.064. Hot-wall chemical vapor deposition experiments revealed that compound 1 is suitable as a precursor for deposition of copper films in the temperature range 170–260 °C. 相似文献
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Methods for synthesizing bistolane liquid crystal materials with lateral methyl and ethyl substituents are presented. Some of the bistolanes are nematic at room temperature. These highly conjugated mesogens exhibit wide nematic ranges, small enthalpies of fusion, high birefringence and modest viscosity. Their potential applications for flat panel displays employing light scattering or Bragg reflection and for infrared optically phased arrays are foreseeable. 相似文献
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Kuo-Kai Shyu Yu-Te Wu Tzong-Rong Chen Hui-Yun Chen Hui-Hsin Hu Wan-Yuo Guo 《Nonlinear dynamics》2010,61(3):363-372
The fetal cortical complexity is a significant quantification for assessing the development of fetal brain. This study attempts
to quantify the development of fetal cortical complexity using the concept of fractal dimension (FD) analysis. Thirty-two
fetal MR images were selected from Taipei Veterans General Hospital at 27–37 weeks of gestational age (GA). To investigate
the FD of fetal cortical complexity, the entropy based information fractal dimension method (FD
EBI), which is modified from Box-Counting method, was adopted and extended from 2D to 3D. The FD results from overall whole fetal
brains show that the increase of cortical complexity is highly correlated with the gestational age of the fetus. Moreover,
the FD values of right hemispheric brain are larger than those of left hemispheric brain, show that the development of right
hemispheric fetal cortical complexity earlier than the left. These results are in good agreement with normal fetal brain development
and suggest that the FD is an effective means for the quantification of fetal cortical complexity. 相似文献
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Left ventricular 4D echocardiogram motion and shape analysis 总被引:1,自引:0,他引:1
The article describes the methodology and the processes of modeling the function and the motion of left ventricle using transesophageal echocardiograph. The parameters can be used in studying the functionality of left ventricle, the status of abnormality of myocardial, and the geometric and morphological of left ventricle in shape analysis. The parameters describes the motion of left ventricle are the left ventricular (LV) floating long axis, the morphological parameters. The LV morphological parameters describe the wall motion, the LV chamber cavity variation, the effective R-ratio of endomyocardial chamber of LV, the area surface curvature, and the global surface curvature circularity. The parameters such as stroke volume, ejection fraction used in evaluation of LV functions are also extracted. 相似文献