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161.
Brahmi Y Katir N Hameau A Essoumhi A Essassi el M Caminade AM Bousmina M Majoral JP El Kadib A 《Chemical communications (Cambridge, England)》2011,47(30):8626-8628
Controlled titanium alkoxide mineralization in the presence of phosphonated, dendrimeric nano-building blocks provides a new family of hierarchically porous dendrimer-bridged titanium dioxide materials. 相似文献
162.
S. Khamlichi X. J. Yu D. Muller J. Jozefonvicz S. Roeland R. Fuks 《Macromolecular Symposia》1988,19(1):155-161
A new polymeric material was prepared from polystyrene beads with N-substituted amidines and rendered hydrophilic with sulfonate and N-hydroxyethylsulfamoyl groups. It was synthesized by reacting the p-chlorosulfonyl polystyrene with ethanolamine followed by the Michael-like addition of the terminal OH of the polymer (PSEa) to N-t-butyl-N'-phenylpropenamidine 1 thus leading to the final polymer PSEaAm. Its affinity constant for human α-thrombin calculated from the Langmuir adsorption isotherms was about 106 M−1, a value comparable to the one estimated for polystyrene modified with L-arginine methyl ester. This new material was used as stationary phase in affinity chromatography of thrombin confirming a strong and specific interaction between the positively charged amidinium groups and the enzyme at pH = 7.4 and desorption at pH = 10 and high ionic strength. 相似文献
163.
164.
Poly[ethylene‐co‐(1‐octene)] nanocomposites with different microstructures were prepared with two kinds of organoclay by melt intercalation. X‐ray diffraction and transmission electron microscopy were used to characterize the morphology of the composites. Linear storage moduli of the composites in the melt state were found to increase greatly with increasing the extent of dispersion of silicate layers and showed an obvious sensitivity to the morphologies of the composites. 相似文献
165.
Acta Mathematica Sinica, English Series - We find on a monoid M the complex-valued solutions f, g : M → ? such that f is central and g is continuous of the functional equation $$f\left(... 相似文献
166.
Abdellatif M. Salah Eldin 《Heteroatom Chemistry》2003,14(7):612-616
2‐Amino‐1,1,3‐tricyano‐3‐bromopropene was obtained from bromination of 2‐amino‐1,1,3‐tricyanopropene (malononitrile dimer) with N‐bromosuccinimide. This bromo derivative reacts with hydrazine hydrate, phenyl hydrazine, and hydroxylamine hydrochloride to afford pyridazine and oxazine derivatives, respectively. In base‐catalyzed reactions with primary aromatic amines and anthranilic acid derivatives, it produces N‐aryl pyrrol‐3,5‐dicarbonitrile and pyrrolo[1,2‐a]quinazolin‐5‐imine, or pyrrolo[1,2‐a]quinazolin‐5‐one derivatives, respectively. The structures of the newly synthesized heterocycles were established on the basis of elemental analyses and spectral data. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:612–616, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10199 相似文献