排序方式: 共有3条查询结果,搜索用时 15 毫秒
1
1.
Christos L. Chochos Dionysia Papakonstandopoulou Solon P. Economopoulos Vasilis G. Gregoriou 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):419-431
A series of polyethers consisting of a modified terfluorenediol connected with a nonconjugated spacer were synthesized and characterized in respect to their thermal, electrochemical, optical and morphological properties. The polymers were further investigated as thin deposits with the use of the FT‐IR technique after thermal (200°C for 30 min) and photo‐oxidation treatment. After thermal treatment no generation of the carbonyl stretching mode of the fluorenone moiety is observed, while after photo‐oxidation in various times (between 5 to 30 min) the appearance of the fluorenone unit is well established. Furthermore, the length of the flexible spacer used influenced the optical properties of the polyethers after thermal treatment. In particular, odd ones showed more intensely the low energy emission band at 520 nm after the thermal treatment in contrast to even ones. 相似文献
2.
Konstantinos Kyriakos Dionysia Aravopoulou Lukas Augsbach Josef Sapper Sarah Ottinger Christina Psylla Ali Aghebat Rafat Carlos Adrian Benitez-Montoya Anna Miasnikova Zhenyu Di André Laschewsky Peter Müller-Buschbaum Apostolos Kyritsis Christine M. Papadakis 《Colloid and polymer science》2014,292(8):1757-1774
Thermoresponsive block copolymers comprising long, hydrophilic, nonionic poly(methoxy diethylene glycol acrylate) (PMDEGA) blocks and short hydrophobic polystyrene (PS) blocks are investigated in aqueous solution. Various architectures, namely diblock, triblock, and starblock copolymers are studied as well as a PMDEGA homopolymer as reference, over a wide concentration range. For specific characterization methods, polymers were labeled, either by partial deuteration (for neutron scattering studies) or by fluorophores. Using fluorescence correlation spectroscopy, critical micellization concentrations are identified and the hydrodynamic radii of the micelles, r h mic , are determined. Using dynamic light scattering, the behavior of r h mic in dependence on temperature and the cloud points are measured. Small-angle neutron scattering enabled the detailed structural investigation of the micelles and their aggregates below and above the cloud point. Viscosity measurements are carried out to determine the activation energies in dependence on the molecular architecture. Differential scanning calorimetry at high polymer concentration reveals the glass transition of the polymers, the fraction of uncrystallized water and effects of the phase transition at the cloud point. Dielectric relaxation spectroscopy shows that the polarization changes reversibly at the cloud point, which reflects the formation of large aggregates upon heating through the cloud point and their redissolution upon cooling. 相似文献
3.
Dionysia Papagiannopoulou George Makris Charalambos Tsoukalas Catherine P. Raptopoulou Aris Terzis Maria Pelecanou Ioannis Pirmettis Minas S. Papadopoulos 《Polyhedron》2010
The synthesis and structural characterization of the neutral rhenium complex fac-[Re(NSO)(CO)3], Re-1, where (NSO) is a tridentate bifunctional chelating agent, 3-(carboxymethylthio)-3-(1H-imidazol-4-yl)propanoic acid (1), is presented. The complex crystallized from methanol–water and its structure was assigned by IR and 1H, 13C NMR spectroscopies and X-ray crystallography. Furthermore, the analogous technetium complex fac-[99mTc(NSO)(CO)3], 99mTc-1, was synthesized in high yield by reacting ligand 1 with the fac-[99mTc(OH2)3(CO)3]+ precursor for 30 min at 85 °C. The tracer complex was found to be more than 95% stable in the L-histidine challenge experiment. Our data indicate that the bifunctional NSO chelating agent 1 can be successfully applied for the development of potential 99mTc-radiopharmaceuticals. 相似文献
1