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51.
The dynamic viscoelastic response of the two-phase polymer blend systems shows the characteristics of the thermorheologically complex materials. In this paper theoretical equations for describing the dynamic viscoelastic response of such polymer blend systems have been established by means of the mechanical modeling technique. The dynamic viscoelastic response of the blend systems at any blend composition can be predicted theoretically by using the equations established, provided that the dynamic viscoelastic response of the two pure components and the mechanical model parameters are known in advance. Thus, we provide an effective method for studying the dynamic mechanical properties and the molecular relaxation characteristics of the two-phase polymer blend systems. 相似文献
52.
Urea can be sorbed by coordination (or complexation)with transitional metalpolyacrylic acid complex and transitional metal-polyacrylamide containing polyethylenepolyamine ligand complexes. The experimental results indicate that the sorbents can sorb about 60mg urea per gram of sorbent at 37℃ and the concentration of urea was 1300.0rag/1 in NaH_2PO_4 and Na_2HPO_4 buffer solution (pH=7.0) and the urea sorption capacity was affected by many factors such as other competive ligands, sorption time, pH and the concentration of urea. 相似文献
53.
合成和表征了一种新的Schiff碱配合物MnL(ClO4)*3H2O(1)(其中L为n(水杨醛)∶n(二乙撑三胺)=1∶1缩合而成的Schiff碱).1与FeSO4*7H2O和K3[Fe(ox)3]*3H2O(ox=oxalate)进一步反应,生成了双金属层状配位聚合物{[MnL][FeⅡFeⅢ(ox)3]*1.5H2O}∞(2).IR和Mssbauer谱测定结果表明,2具有二维层状结构,其阴离子层由[FeⅡFeⅢ(ox)3]-单元构成.变温磁化率(5K~100K)测试结果表明,2中的自旋载体之间存在反铁磁交换作用.5K时的磁滞现象表明2在低温时可能存在铁磁有序,这可能是亚铁磁或自旋倾斜造成的. 相似文献
54.
Meng Wang 《European Polymer Journal》2007,43(11):4613-4618
In this study the optical property and film morphology of a conjugated polymer, poly(9,9-dihexylfluorene-alt-2,5-dihexyloxybenzene) (PF6OC6), are investigated. It is found that the intensity of the 0-1 emission relative to the 0-0 emission in the PL spectra and the full width at the half-maximum (fwhm) of PL spectra of the PF6OC6 films decrease firstly and then increase with increasing the annealing temperature. The polymer films also exhibit different morphological features after annealing at different temperatures. The optical and morphological results suggest that the vibronic structure of PF6OC6 is closely related to the film morphology, and its formation is enhanced in the amorphous (or less ordered) films and inhibited in the ordered films. 相似文献
55.
Two molecular imprinting polymer (MIP) monolithic columns with (S)-(-)-1,1'-bi-2-naphthol and (R)-(+)-5,5',6,6',7,7',8,8'-octahydro-1,1'-bi-2-naphthol as the templating molecules, respectively, have been prepared by in situ polymerization using 4-vinylpyridine and ethylene dimethacrylate as functional monomer and cross-linker, respectively. The columns with good flow-through properties were obtained by changing the molar ratio of the functional monomer and the template molecule. The effects of mobile-phase composition on separation of enantiomers were systematically investigated. The results indicate that hydrophobic interaction in aqueous solution and hydrogen-bonding interaction in ACN between the enantiomers and polymers could play important roles in the retention and resolution. The effects of chromatographic conditions, such as flow rate, column temperature, sample loading, on the enantioseparation were also studied. Further, these two MIP columns show a cross-reactivity. 相似文献
56.
Tsutomu Oishi Kensoh Kagawa Minoru Fujimoto 《Journal of polymer science. Part A, Polymer chemistry》1995,33(8):1341-1352
Two types of optically active N-[N′-(α-methylbenzyl)amino/carbonyl-n-alkyl]maleimides (MBAC) were synthesized from maleic anhydride, 6-amino-n-caproic acid (or 12-amino-n-dodecanoic acid), and (R)-(+)-α-methylbenzylamine. Radical homopolymerizations of MBAC were performed in several solvents at 60 and 110°C for 24 h to give optically active polymers. Radical copolymerizations of MBAC were performed with styrene (ST) and methyl methacrylate (MMA) in dioxane at 60°C. The monomer reactivity ratios and the Alfrey-Price Q-e values were determined. Chiroptical properties of the polymers and copolymers were investigated. © 1995 John Wiley & Sons, Inc. 相似文献
57.
58.
An increase is found in the reactivity of organomercury and organothallium nitroxyl mono- and biradicals of the imidazoline type in comparison with the analogous compounds without organometallic fragments. This is explained by the formation of coordination bonds NHg, NTl, and NOHg.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 224–226, January, 1993. 相似文献
59.
The determination of zinc ion (1-60 ng ml−1) by anodic square-wave stripping voltammetry on an anion-exchange perfluorinated polymer Tosflex mercury film electrodes (TMFE) was evaluated. The detection limit was 0.1 ng ml−1 Zn(II). The effect of various organic compounds (gelatin, albumin, starch, camphor, humic acid, Triton X-100, sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB)) is explored. The results indicate that due to the size-exclusion and ion-exchange properties of Tosflex film, the TMFE is considerably more resistant to organic interference than the bare mercury film electrode. 相似文献
60.
We introduce a new Monte Carlo algorithm for the self-avoiding walk (SAW), and show that it is particularly efficient in the critical region (long chains). We also introduce new and more efficient statistical techniques. We employ these methods to extract numerical estimates for the critical parameters of the SAW on the square lattice. We find=2.63820 ± 0.00004 ± 0.00030=1.352 ± 0.006 ± 0.025v=0.7590 ± 0.0062 ± 0.0042 where the first error bar represents systematic error due to corrections to scaling (subjective 95% confidence limits) and the second bar represents statistical error (classical 95% confidence limits). These results are based on SAWs of average length 166, using 340 hours CPU time on a CDC Cyber 170–730. We compare our results to previous work and indicate some directions for future research. 相似文献