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1.
A series of ternary lanthanide complexes Ln (C6H5CHOHCOO)3(phen) (H2O) (Ln= La, Ce, Pr, Nd, Sm, Eu) were synthesized with α-hydroxyl-phenyl-acetic acid and 1, 10-phenanthroline (phen) as ligands. The sturcture and property of complexes were characterized by elemental analysis, IR, 1^H-NMR, UV and TGA, and the coordinate mede of both ligands was discussed. It was shown that the co-ordinate mode of 1, 10-phenanthroline was chelated, while α-hydraxyl-phenyl-acetate ion was monedentate or bridging. The mechanism of thermal determinde by thermogravimetry was indicated that the degree of co-ordinate ability of ligand was: α-hydroxyl-phenyl-acetate ion 〉 1, 10- phenanthroline(phen).  相似文献   

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To prepare lipophilic α-zirconium phosphate with high grafting ratio and thermal stability(OZrP-HT) and explore its potential application in thermal-plastic polymers,a novel method was developed by surface lipophilicity enhancement strategy.The commercial a-zirconium phosphate(a-ZrP) was pre-intercalated by n-propylamine(PA) and grafted by silane coupling agents.Then the pre-intercalated PA was removed by heattreatment,and the obtained OZrP-HT was utilized to fabricate the phosphorous-containing polyester(P-co-PET)/OZrP-HT nanocomposites by melt-blending method.The prepared OZrP-HT and P-co-PET/OZrP-HT nanocomposites were characterized by Wide Angle X-ray Diffraction(WAXD),Fourier Transform Infrared Spectroscopy(FTIR),Thermogravimetric Analysis(TGA),Transmission Electron Microscope(TEM),etc.The results show that OZrP-HT with high grafting ratio(13.78 wt%) and thermal stability(T_(onset)= 368℃) was successfully prepared via this novel method and was uniformly intercalated by P-co-PET molecular chains.OZrP-HT had no significant effect on the fiber processability of P-co-PET polymer,and flame retardant properties of(P-co-PET)/OZrP-HT nanocomposites were improved.This method may be suitable for organic modification of general inorganic layered compounds and could extend the potential applications in thermo-plastic polymers.  相似文献   

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The polystyrene/reetorite nanocomposites were prepared by free radical polymerization of styrene containing dispersed organophilic rectorite. The structures and thermal properties of these hybrids have been investigated by X-ray diffraction (XRD), fourier transform infrared (FT-IR), positron annihilation spectroscopy (PAS) and thermal gmvimetric analysis (TGA) techniques. It was found that exfoliation of reetorite in polystyrene (PS) matrix was achieved. The average free-volume radius in the PS/clay nanocomposites is generally same as that in PS. Along with increment of reetorite contents, the interface between reetorite and polystyrene matrix increases, and the free-volume concentration decreases obviously. And the polystyrene nanocomposites have higher thermal deeomrosition temoemture than oure PS.  相似文献   

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1 Introduction General synthetic polymers such as polyethylene, polyvinyl chloride, polystyrene etc. have been produced and used in large quantities. They are very cheap, but their wastes are difficult to decompose in nature so to cause environmental pollution .In order to overcome such disadvantage, various kinds of biodegradable synthetic polymers such as polyactic acid, aliphatic polyester, polyvinyl alcohol complexes etc. have been researched~([1]). However, they are expensive, so cannot b…  相似文献   

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IntroductionThe separation technique of solvent extractionbased on reversible chemicalcomplexation can havehigh capacity and high selectivity for separatingpolar organic solutes from dilute solutions[1,2 ] .Many researchers have investigated the extractio…  相似文献   

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1 Results Rosin is a sort of important renewable resources,which is a foremost product of our country forestry. It has very important meaning to modify the rosin based on its molecule structure and active group, to develop some deep processing products, and to endure with rosin new characteristic[1]. This work uses the rosin and acrylic acid to form rosin adduct, and then reacted with 2-hydroxyethyl methacrylate (HEMA) to form ester under the different condition. The effect of different ratios with the adduct and HEMA, catalyst types and levels on the esterification was investigated. The molecular structure of the adduct and the ester was characterized with IR spectrum. Their thermal stabilities were conducted with thermal analyzer. Experiment results show that the rosin ester was prepared successful, the best esterification condition was found out. The thermal stability of the rosin ester from acrylic acid rosin and HEMA was improved. The rosin ester may be used as negative photoresist[2].  相似文献   

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Interesting and diverse tautomerizations and intramolecular hydrogen bondings of the chiral α-nitroester, α-nitrosoester and α-ketoester are described and rationally interpreted.  相似文献   

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A hand-made biodegradable intravascular stent with zig- zag structure has been developed, which made from polylactic acid ( PLA ) braided thread and poly-eaprolactone ( PCL ) tube. This paper showed the preparation process of the PLA braded thread and stent, and discussed the heat setting process of the stents. The sixteen groups of stents were made for the heat setting experiments, discussing two factors on four levels. Radial compression behavior of stents was tested by plate compression method. The result showed that both the heat setting temperature and time had significant effects on stent compression strength. The compression recovery rate was mainly affected by heat setting temperature. The optimized heat setting condition should be 90-100℃ for 45 rain.  相似文献   

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The current density is rather low in solid bipolar membranes, because the water transfer rate is relatively slow across solid bipolar membranes made of solid ion-exchange materials. This paper describes the use of polymer solutions, such as phosphatic poly(vinyl alcohol) solution, poly(acrylic acid) solution and poly(vinyl alcohol) solutions with dispersed cation/anion-exchange resin particles to prepare bipolar membranes. The 0. 1 mol/L NaOH and the 0.05 mol/L H2SO4 were used to test the performance of the bipolar membranes. For a fixed liquid layer thickness, both the current density and the selectivity increase with the concentration increase of a polyelectrolyte solution. The maximum current density measured in the experiment was 1497A/m^2 with a selectivity of 96.8%.  相似文献   

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1 Results The dominant position of molecular oxygen as the oxidant for bulk chemical oxyfunctionalizations is due to the fact that it is the only economically and environmentally friendly feasible oxidant for large scale processing.But molecular oxygen is not better oxidant than others,such as PhIO,NaOCl,H2O2,alkyl hydroperoxides,percarboxylic acids,magnesium monoperoxyphthalate.So we have to select high reactivity and general utility catalyst.The oxidation of hydrocarbons catalyzed by transition metal complexes has been extensively studied[1-2].  相似文献   

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1Introduction PowergenerationisanimportantcomponentofthedevelopmentofTGP .Theinstalledcapacityandtherunner’sdiameterofageneratingunithavebeenvaryingallalongwiththechangesofdifferentcomparativeschemesofthenormalpoollevelduringtheresearchoftheTGPdevelopmentinthelasthalfcentury.Asthegeneratingunitswithalargeoutputhavebeenputintoopera tionsincethe 1 980s,researchesoftheTGPgeneratingunitshavebeenempha sizedontherepresentativecapacityof5 0 0mwfortheschemeofa 1 5 0mnor malpoolleveland 70 0mwfor…  相似文献   

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Titania (TiO2) is an environmental-friendly photo- catalyst material with high stability and efficiency, so its preparation methods received extensive atten- tion[1―4], and the products were advanced from dis- persed nano-powder and fastness nano-film[5,…  相似文献   

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张利  Li  Yubao  Zhou  Gang  Wu  Lan  Mu  Yuanhua  Yang  Zheng 《高技术通讯(英文版)》2007,13(1):31-35
Chitosan/nano-hydroxyapatite composites with different weight ratios were prepared through a co-precipitation method using Ca(OH)2, H3PO4 and chitosan as starting materials. The properties of these composites were characterized by means of TEM, IR, XRD, TGA, burn-out tests and universal matertial testing machine. The results showed that the HA synthesized here was poorly crystalline carbonated nanometer crystals and dispersed uniformly in chitosan phase and there was no phase-separation between the two phases. The addition of n-HA resulted in a decrease of decomposing temperature of chitosan. Because of the interactions between chitosan and n-HA, the mechanical properties of these composites were improved, and the maximum value of the compressive strength was measured to be about 120MPa corresponding to the chitosan/n-HA composite with a weight ratio of 30/70.  相似文献   

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IntroductionAchelatefiltermembraneistheproductofmodernmembranetechnologycombinedwithchelateaffinitytechnology[1~ 6] Asthecarrierofchelatingagent,thechelatefiltermembranewithdefiniteporeshaschelatingagentonitsinsideandoutsidesurface Theob jectproductswill…  相似文献   

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We reported that layered polymer crystals are obtained by the topochemical polymerization of 1,3-diene monomers and provided as host material for organic intercalation. For intercalation using various long-alkyl amines as the guest species, its reaction behavior, mechanism, characteristics, and potential to application have been clarified. We also succeeded in the synthesis of several host layered polymer crystals with different tacticities and layer structures. We describe here intercalation using various stereoregular poly(muconic acid)s (PMA) and n-alkylamines as the host and guest compounds, respectively. The reaction behavior and the layered structure of the obtained ammonium polymers are discussed from the viewpoint of stereochemical structure of the host polymers.  相似文献   

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Bioactive glasses and ceramics have been widely investigated for bone repair because of their excel-lent bioactive characteristics. However, these biomaterials undergo incomplete conversion into a bone-like material, which severely limits their biomedical application. In this paper, borosilicate bioac-tive glasses were prepared by traditional melting process. The results showed that borosilicate glasses possessed high biocompatibility and bioactivity. In addition, when immersed in a 0.02 mol/L K2HPO4 solution, particles of a borate glass were fully converted to HA. The desirable conversion rate to HA may be achieved through the adjustment of the B2O3/SiO2 ratio. The results of XRD and FTIR analysis indicated that the degradation product was carbonate-substituted hydroxyapatite, which was similar to the inorganic component of bone.  相似文献   

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