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Ohkawa K Hayashi S Kameyama N Yamamoto H Yamaguchi M Kimoto S Kurata S Shinji H 《Macromolecular bioscience》2009,9(1):79-92
A synthetic route is described for collagen-like polypeptides constructed from O-phospho-L-hydroxyproline [Hyp(PO(3)H(2))] residues. Using the synthetic polypeptides and a natural protein, gelatin, fine fibers and their network structures (ESNWs) were prepared via electrospinning. The composite ESNWs can induce the mineralization of calcium phosphate. The phosphoryl groups of the Hyp(PO(3)H(2)) residues affect both the crystalline phase and amount of the calcium phosphate, depending on the chemical structure in the repeating sequence. The composite ESNWs can be developed as a biocompatible replacement of the extracellular matrix of hard tissues, and thus can be applied as dental materials for restoration of dental cavities or as a sealant for pits and fissures. 相似文献
54.
Mina Mazzeo Marina Lamberti Ilaria D'Auria Stefano Milione Jonas C. Peters Claudio Pellecchia 《Journal of polymer science. Part A, Polymer chemistry》2010,48(6):1374-1382
New Group 3 metal complexes of the type [LM(CH2SiMe3)2(THF)n] supported by tridentate phosphido‐diphosphine ligands [(o‐C6H4PR2) 2 PH; L1‐H : R = iPr; L2‐H : R = Ph] have been synthesized by reaction of L1‐H and L2‐H with [M(CH2SiMe3)3(THF)2)] (M = Y and Sc). All the new complexes [(o‐C6H4PR2) 2 PM(CH2SiMe3)2(THF)n] [M = Y, R = iPr (1), R = Ph (2); M = Sc, R = iPr (3), R = Ph (4)] were studied as initiators for the ring opening polymerization of lactide. The yttrium complexes ( 1 and 2 ) exhibited high activity and good polymerization control, shown by the linear fits in the plot of number‐averaged molecular weight (Mn) versus the percentage conversion and versus the monomer/initiator ratio and by the low polydispersity index values. Interestingly, very good molar‐mass control was observed even when L ‐Lactide was polymerized in the absence of solvent at 130 °C. A good molar‐mass control but lower activities were observed in the polymerization reaction of lactide promoted by the analogous scandium complexes 3 and 4 . © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1374–1382, 2010 相似文献
55.
The title compound 3-(4-bromobenzyloxy)-6-morpholinopyridazine(C15H16BrN3O2) was synthesized,and its crystal structure was studied.It crystallizes in the triclinic system,space group P with a = 8.3408(17),b = 8.8620(18),c = 10.832(2) ,α = 108.09(3),β = 91.28(3),γ = 100.90(3)°,Dc = 1.562 g/cm3,Z = 2,λ = 0.71073 ,μ(MoKα) = 2.769 mm-1,Mr = 350.22,V = 744.5(3) 3,F(000) = 356,the final R = 0.0522 and wR = 0.1366 for 2016 observed reflections with I > 2σ(I).In the crystal structure,the morpholine ring adopts a chair conformation with O(2) and N(3) atoms at the flap positions-0.656(7) and 0.622(6) out of the mean plane formed by the other four C atoms,respectively.These molecules generate centro-symmetric dimers through intermolecular π-π interaction. 相似文献
56.
An optimal hydrophobic ionic liquid was discovered as a solvent for highly enantioselective glyoxylate-ene reactions catalyzed by a chiral bis(oxazoline)–copper complex. The reactivity and stereoselectivity were highly dependent upon the property of the ionic liquids; reactions between olefins and ethyl glyoxylate in [Bmim]SbF6 at ambient temperature provided remarkably enhanced reactivity and stereoselectivity, which greatly exceed those of the corresponding reactions in dichloromethane. Furthermore, the metal–ligand complex was readily recycled up to eight times while exhibiting no significant decrease in reaction efficiency. 相似文献
57.
M.N.K. Chowdhury M.W. Khan M.F. Mina M.D.H. Beg Maksudur R. Khan A.K.M.M. Alam 《Radiation Physics and Chemistry》2012,81(10):1606-1611
Grafting of styrene/maleic anhydride and methyl methacrylate/maleic anhydride binary monomers onto the low density polyethylene film was performed using the γ-ray irradiation technique. Then, the synthesized grafted films were treated with different ammonia derivatives for developing chelating functionalization. These chelating products were characterized by the gravimetric method as well as by the Fourier transformed infrared spectroscopic method, and were used for removal of arsenic and some heavy metals from aqueous solutions. The optimum absorbed dose of 30 kGy reveals the graft yielding of about 325% in the films. Uptake of arsenic and some heavy-metal ions (Cr(III), Mn(II), Fe(III), Ni(II), Cu(II) and Pb(II)) from contaminated water by the chelating functionalized films (CFF) was examined by an atomic absorption spectrophotometer. The maximum arsenic removal capacity of 5062 mg/kg has been observed for the film treated with hydroxylamine hydrochloride. The CFF prepared by semicarbazide and thiol analogs show affinity toward the metal ions with an order: Cu(II)>Fe(III)>Mn(II) etc. The results obtained from this study indicate that the functionalized films show good chelating and ion-exchange property for metal ions. 相似文献
58.
Mohammad Ali Rasouli Mohammad Mahdavi Parviz Rashidi Ranjbar Mina Saeedi Abbas Shafiee Alireza Foroumadi 《Tetrahedron letters》2012,53(52):7088-7092
This work describes a green and efficient one-pot synthesis of N-alkyl-2-(2-oxoazepan-1-yl)-2-arylacetamide derivatives via an Ugi four-center, three-component reaction of 6-aminohexanoic acid, aromatic aldehydes, and isocyanide derivatives in water under reflux conditions in the absence of a catalyst. 相似文献
59.
60.
Mina AbdolahZadeh A. Catarina C. Esteves Sybrand van der Zwaag Santiago J. Garcia 《Journal of polymer science. Part A, Polymer chemistry》2014,52(14):1953-1961
In this article, the first generation of healable sol–gel based polymers is reported. A dual organic–inorganic crosslinked network is developed containing non‐reversible crosslinks and reversible (tetrasulfide) groups. The designed polymer architecture allows thermally induced mesoscale flow leading to damage closure followed by interfacial strength restoration due to reformation of the reversible groups. While the reversible bonds are responsible for the flow and the interface restoration, the irreversible crosslinks control the required mechanical integrity during the healing process. The temperature dependent gap closure kinetics is strongly affected by the crosslinking density and tetrasulfide content. Raman spectroscopy is used to explain the gap closure kinetics in air and dry nitrogen. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1953–1961 相似文献