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1.
The vapor-liquid polycondensation of cyclohexylphosphoric dichloride with hydroquinone was investigated. The influence of the temperature, reaction time, base concentration, and molar ratio of reagents on the yield, inherent viscosity, and molecular weight of the obtained polymer was studied. Second order, central, composite, rotatable experimental design was used in order to carry out this work and to mark limits of the experimental field for optimal yields and high inherent viscosities.  相似文献   
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Some mixed phosphites having two different alkyl chain were obtained as forerunners for mixed phosphates Mixed dialkyl phosphates were obtained in good yields (40-80%) by phase transfer catalysis in liquid-liquid sistem, starting from different dialkyl phosphites and aliphatic alcohols. The reaction conditions were optimized in order to obtain good yields in phosphites and phosphates respectively. Compounds were analyzed by IR, P 31 -NMR.  相似文献   
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Ambazone is a pharmaceutical compound that possesses antiseptic activity and tested as well for anti-tumor properties. Metal complexes of Zn(II), Fe(III), and Cu(II) containing ambazone as ligand were synthesized using a molar ratio salt:ligand of 1:1, heating the mixture up to 50 °C for 6 h. Coordination compounds were characterized by thin-layer chromatography, FT-IR spectroscopy, elemental analysis, and thermal behavior. The non-isothermal experiments were carried out in order to investigate the thermal degradation process of these complexes and were performed in a dynamic air atmosphere at a heating rate β = 10 °C min?1 from ambient temperature, up to 500 °C. It was revealed that decomposition process is a multistadial one.  相似文献   
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FTIR, UV-VIS and EPR spectra of manganese doped lead-tellurate glasses with composition xMnO·(100-x)[4TeO2·PbO2] where x=0, 1, 5, 10, 20, 30, 40mol% have been studied. The FTIR spectra show the formation of the Mn-O-Pb and Mn-O-Te bridging bonds by increasing of MnO concentration. The UV-VIS spectra show the Mn(+3) species exhibit pronounced absorption, which masks the Mn(+2) spin-forbidden absorption bands when Mn(+2) ions are in high concentrations in these glasses. The EPR spectra exhibit resonance signals characteristic of Mn(+2) ions. The resonance signal located at g≈2 is due to Mn(+2) ions in an environment close to octahedral symmetry, whereas the resonance at g≈4.3 and 3.3 are attributed to the rhombic surroundings of the Mn(+2) ions. The increase in the MnO content gives rise to absorption at g≈2.4 and the paramagnetic ions are involved in dinuclear manganese centers.  相似文献   
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ABSTRACT: BACKGROUND: The isoflavonoid genistein represents the major active compound from soybean, the vegetalproduct from Glycine max (Fabaceae). The aim of this study is to prove that genistein wasincorporated in two semisynthetic cyclodextrins, beta-cyclodextrin derivatives:hydroxypropyl-beta-cyclodextrin and randomly-methylated-beta-cyclodextrin as well as to compare the anti-inflammatory activity of genistein with that of genistein incorporated inthese two types of semisynthetic cyclodextrins. RESULTS: The animal studies were conducted on 8-week old C57BL/6 J female mice. Inflammation wasinduced in both ears of each mouse by topical application of 10 micrograms 12-Otetradecanoylphorbol-3-acetate dissolved in 0.1 ml solvent (acetone : dimethylsulfoxide in amolar ratio 9:1). Thirty minutes later treatment was applied. The inflammatory reaction wascorrelated with increased values in ear thickness. Treatment with genistein and genisteinincorporated in the two cyclodextrins led to decreased values for ear thickness. Better antiinflammatoryaction was found for the complexes of genistein. Both haematoxylin-eosinanalysis and CD45 marker expression are in agreement with these findings. CONCLUSIONS: Results allow concluding that genistein is an active anti-inflammatory phytocompound andits complexation with hydrophilic beta-cyclodextrin derivatives leads to a stronger antiinflammatoryactivity.  相似文献   
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Journal of Thermal Analysis and Calorimetry - The use of cyclodextrins as carrier molecules is currently highly researched since they can improve not only the apparent water solubility and...  相似文献   
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