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991.
New highly substituted benzyl diallylamino monomers were prepared from substituted phenols by use of the Mannich reaction. Their ability to cyclopolymerize as the free phenols and the structures and properties of the pomers formed were investigated. 相似文献
992.
The synthesis and spectroscopic studies of a convex bis-porphyrin based molecular tweezer are reported. The complexation of small bidentate ligands by metallated derivatives of the bis-porphyrin host were monitored through UV–visible and 1H NMR spectroscopy and yielded large association constants. 相似文献
993.
Tomáš Bříza Martin Havlík Bohumil Dolenský Zdeněk Kejík Pavel Martásek 《Supramolecular chemistry》2013,25(3):237-242
Highly functionalized fluorinated porphyrins were synthesized by a convergent strategy. Nucleophilic substitution using fluorinated branched unit and 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin afforded highly functionalized fluorinated porphyrin 8 containing 24 fluorinated chains in the peripheral region. 相似文献
994.
Ryan T. Chester Roland de Marco Mauro Mocerino Brian W. Skelton Allan H. White 《Supramolecular chemistry》2013,25(6):479-485
The tetra-isopropyl ethers of calix[4]arene and p-t-butylcalix[4]arene have been isolated in the cone conformation, and structurally characterised as chloroform solvates. Thermogravimetric analysis demonstrated that the parent isopropylcalix[4]arene solvate is significantly more stable than the p-t-butylcalix[4]arene analogue, retaining the solvent up to a temperature of 125°C. It was found that the calix[4]arene ether sublimes at atmospheric pressure, and solvent-free crystals appropriate for structure determination were produced at reduced pressure. The p-t-butylcalix[4]arene ether was also isolated without solvent in the lattice, but in this case the calixarene was crystallised from acetone, as sublimation did not produce crystals of sufficient quality. 相似文献
995.
Martin T. Palou Ľubomír Bágeľ Vladimír Živica Marta Kuliffayová Tomáš Ifka 《Journal of Thermal Analysis and Calorimetry》2013,113(1):385-394
Various hydrothermal curing regimes were used to investigate the hydration and physical characteristics of two kinds of inorganic binder composites: high alumina cement–silica fume–Portland cement and high alumina cement–silica fume–sodium polyphosphate. Simultaneous thermal analysis (DTA and TG) was used to identify temperature ranges of thermal decomposition of cured samples and to characterize the nature of hydrate products. Two kinds of products are formed. The first ones consist of C3AH6, AH3, calcium carbonate (C–C) as a product of carbonation, and C3AH1.5 resulted from the partial decomposition of C3AH6 under higher hydrothermal pressure. The second ones are the products formed by acid–base reaction between monocalcium aluminate and sodium polyphosphate to form NaCaPO4·xH2O and Al2O3·xH2O that could convert to chemically bonded ceramic binders like hydroxyapatite (Ca5(PO4)3OH) and gibbsite (Al(OH)3). These two hydroceramic products formed under these conditions act also as binder and could be useful as cement binders for the protection of petroleum, gas, or geothermal wells. Mercury intrusion porosimeter was used for the estimation of the pore structure parameters of the composites. It turned up that longer curing time coupled with higher hydrothermal pressure has improved the pore structure of the first composite, while that of the second has remained unchanged. 相似文献
996.
997.
998.
Alexandre Zagdoun Dr. Aaron J. Rossini Dr. Matthew P. Conley Wolfram R. Grüning Martin Schwarzwälder Dr. Moreno Lelli Dr. W. Trent Franks Prof. Dr. Hartmut Oschkinat Prof. Dr. Christophe Copéret Prof. Dr. Lyndon Emsley Dr. Anne Lesage 《Angewandte Chemie (International ed. in English)》2013,52(4):1222-1225
999.
Erhan Bat Theo G. van Kooten Martin C. Harmsen Josée A. Plantinga Marja J. A. van Luyn Jan Feijen Dirk W. Grijpma 《Macromolecular bioscience》2013,13(5):573-583
Form‐stable resorbable networks are prepared by gamma irradiating trimethylene carbonate (TMC)‐ and ε‐caprolactone (CL)‐based (co)polymer films. To evaluate their suitability for biomedical applications, their physical properties and erosion behavior are investigated. Homopolymer and copolymer networks that are amorphous at room temperature are flexible and rubbery with elastic moduli ranging from 1.8 ± 0.3 to 5.2 ± 0.4 MPa and permanent set values as low as 0.9% strain. The elastic moduli of the semicrystalline networks are higher and range from 61 ± 3 to 484 ± 34 MPa. The erosion behavior of (co)polymer networks is investigated in vitro using macrophage cultures, and in vivo by subcutaneous implantation in rats. In macrophage cultures, as well as upon implantation, a surface erosion process is observed for the amorphous (co)polymer networks, while an abrupt decrease in the rate and a change in the nature of the erosion process are observed with increasing crystallinity. These resorbable and form‐stable networks with tuneable properties may find application in a broad range of biomedical applications.
1000.
Vera A. Schulte Dora F. Alves Paul P. Dalton Martin Moeller Marga C. Lensen Petra Mela 《Macromolecular bioscience》2013,13(5):562-572
Designing three‐dimensional (3D) scaffolds for selective manipulation of cell growth is of high relevance for applications in regenerative medicine. Especially, scaffolds with oriented morphologies bear high potential to guide the restoration of specific tissues. The fabrication of hydrogel scaffolds that support long‐term survival, proliferation, and unidirectional growth of embedded cells is presented here. Parallel channel structures are introduced into the bulk hydrogels by uniaxial freezing, providing stable, and uniform porosity suitable for cell invasion (pore diameters of 5–15 µm). In vitro assessment of the scaffolds with murine fibroblasts (NIH L929) shows a remarkable unidirectional movement along the channels, with the cells traveling several millimeters through the hydrogel.