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341.
Synthesis of the Biomimetic Polymer: Aliphatic Diamine and RGDS Modified Poly(d,l-lactic acid) 总被引:4,自引:0,他引:4
Xu Feng NIU Yuan Liang WANG Yan Feng LUO Jun PAN Li Xia GUO 《中国化学快报》2005,16(8):1035-1038
A novel poly(d, /-lactic acid) (PDLLA) based biomimetic polymer was synthesized by grafting maleic anhydride, butanediamine and arg-gly-asp-ser (RGDS) peptides onto the backbone of PDLLA, aiming to overcome the acidity and auto-accelerating degradation of PDLLA during degradation and to improve its biospecificity and biocompatibility. The synthetic copolymer was characterized by FTIR, ^13C NMR and amino acid analyzer (AAA). 相似文献
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The effects of M3O3 (M = Al, Sc etc.) in Cu-ZnO-M2O3 catalysts on methanol synthesis at low pressure were studied with ESR, XPS and TPR spectroscopy. The results of ESR showed that the generation of monovalent cationic defects was because the valence state and electronic charge on the ZnO lattice lost their balance as M3+ doped into ZnO. The induced effect by Sc3+ is stronger than that by Al3+. The results of XPS and TPR indicated that the amount and stabilization of Cu+ on the surface of reduced copper-based catalyst and its catalytic activity were affected by the monovalent cationic defects on the surface of ZnO. 相似文献
344.
由2-氰-5-氟-3H-4-嘧啶酮和取代苯酚钠在常压下反应,合成了7个未见文献报道的2-芳氧基-5-氟-3H-4-嘧啶酮化合物,产率70 ̄87%,结构经IR、^1H NMR和MS证实。 相似文献
345.
By using a micro-bomb calorimeter, the standard enthalpies of combustion of C60 and C70 have been determined to be - (25 947.1±8.5) and - (29 956.1 ± 8.9) kJ/mol respectively. A g. 1. c. analysis indicated that
the amounts of residual organic solvents in the samples were very small, and their effects on the final results were negligible.
The energy of combustion ofC60 determined in this work is in agreement in the uncertainty interval with that determined by means of traditional calorimeter
using macro amount of sample. The enthalpies of formation of these two substances have been derived. The strain energies in
the molecules of C60 and C70 were estimated by a bond energy scheme and by using corannulene as the model compound, the results estimated from different
methods are very close.
Project supported by the National Natural Science Foundation of China (Grant No. 29473143) 相似文献
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A parallel solution combustion synthesis technique was developed for combinatorial materials studies. The vigorous combustion reactions were successfully limited in the microreactors by using a substrate-net-mask microreactor system and the lowest adoptable furnace temperature. Using this technique, a luminescent materials library of Y3Al5O12/Tb(chi) was synthesized with the aid of an ink-jet delivery system. Structure and luminescence characterizations were implemented using X-ray diffraction and UV/X-ray spectroscopies, respectively. The results show that this technique is reliable and applicable to combinatorial study of powder materials with high synthesis temperature. 相似文献
348.
This work describes a structure and kinetic stability study of some complexes with the general formula MN, where M are the alkaline earth metal atoms, Be, Mg, Ca, Sr, and Ba. A complex (A) with two points of attachment to the N5 ring is the most energetically favored for all metals considered here. Except for Be, structure (B) containing a mono‐coordinated metal atom is a transition state corresponding to the metal atom transfer around the N5 ring. Pyramidal structure (C) is kinetically unstable with the low isomerization barrier height, ranging from 0.9 to 6.7 kcal/mol. The dissociation barrier heights for the lowest energy isomers (A) are predicted to be 1.2–18.7 kcal/mol (Be to Ba), indicating that kinetic stability increases from lighter to heavier metal atoms. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献
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