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171.
Pietro Favia Victor H. Perez-Luna Thomas Boland David G. Castner Buddy D. Ratner 《Plasmas and Polymers》1996,1(4):299-326
Fluoropolymer films have been deposited in the glow and afterglow regions of radio frequency glow discharges fed with C2F6−H2 mixtures. Structure, growth rate, composition, and wettability of the films have been investigated by means of atomic force
microscopy, electron spectroscopy for chemical analysis, secondary ion mass spectrometry, and water contact angle measurements.125I labeled baboon fibrinogen in baboon plasma has been used to study the adsorption of the protein onto the films. Protein
retention, i.e., the binding affinity of the adsorbed protein, has been examined by elution with a sodium dodecyl sulfate
solution. Adsorption and retention of fibrinogen were correlated using multivariate statistical methods with the wettability,
the degree of film fluorination, and the CF
x
(1≤x≤3) group distribution of the coatings. This correlation identified the influence of each variable on the adsorption and retention
of fibrinogen onto these substrates. These variables or surface properties can be easily balanced by properly tuning the experimental
conditions of the glow discharge deposition process. 相似文献
172.
Andrea Cappelli Maurizio Anzini Salvatore Vomero Alessandro Donati Lucia Zetta Raniero Mendichi Mario Casolaro Pietro Lupetti Paolo Salvatici Gianluca Giorgi 《Journal of polymer science. Part A, Polymer chemistry》2005,43(15):3289-3304
The macromolecular and aggregate structures of poly[ethyl 1‐methylene‐3‐(4‐methylphenyl)‐1H‐indene‐2‐carboxylate] (poly‐ BF1 ; a new polymer based on a functionalized benzofulvene moiety showing interesting properties, i.e., thermoreversible polymerization/depolymerization behavior, high solubility in the most common organic solvents, and susceptibility to molecular manipulation) have been investigated with NMR spectroscopy, absorption and emission spectrophotometry, and transmission electron microscopy (TEM). Moreover, the polymerization mechanism has been studied to obtain further information on the polymer structure. The collected evidence is consistent in indicating for poly‐ BF1 a vinyl (1,2) polymer structure stabilized by means of aromatic stacking interactions. Furthermore, TEM studies performed on metal replicas have shown that the polymer is liable to give nanostructured aggregates. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3289–3304, 2005 相似文献
173.
Abdiaziz A. Farah William J. Pietro 《Journal of polymer science. Part A, Polymer chemistry》2005,43(23):6057-6072
A series of poly(N‐(ω′‐alkylcarbazoly) methacrylates) tris(bipyridine) Ru‐centered bifunctional polymers with good filming, thermal, and solubility properties were synthesized and characterized. Atom transfer radical polymerization (ATRP) of N‐(ω′‐alkylcarbazoly) methacrylates in solution was used, where Ru complexes with one and three initiating sites acted as metalloinitiators with NiBr2(PPh3)2 as a catalyst. ATRP reaction conditions with respect to polymer molecular weights and polydispersity indices (PDI) of the target bifunctional polymers were examined. Electronic absorption and emission spectra of the resultant functional polymers provided evidence of chromophore presence within a single polymeric chain. The thermal properties of all polymers were also investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and these analyses have indicated that these polymers possess higher thermal stabilities than poly(methyl methacrylate) (PMMA) obtained via free radical polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6057–6072, 2005 相似文献
174.
Pietro De Poi 《Mathematische Nachrichten》2005,278(4):363-378
In this article we study congruences of lines in ?n, and in particular of order one. After giving general results, we obtain a complete classification in the case of ?4 in which the fundamental surface F is in fact a variety, i.e. it is integral, and the congruence is the irreducible set of the trisecant lines of F. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
175.
176.
Pietro Cremaschi 《Chemical physics letters》1984,106(4):286-291
Cross sections of the sequential two-photon ionization of Li2 are evaluated starting from ab initio CI wavefunctions and using different laser wavelengths for the excitation and ionization processes. In agreement with experimental results and previous calculations, a substantial isotope separation is found for the three isotopes of Li2, and a wide spectrum of wavelengths useful for effective isotope enrichment is suggested. Even in with an overcrowded spectrum, the fundamental role of Franck-Condon factors and thermal populations in defining the characteristic resonances of the fractionation process is confirmed. This result suggests a practical way to predict transitions useful for isotope enrichment. 相似文献
177.
178.
Reaction of open-chain and cyclic sym-1,3-diones with N,N-dimethylformamide dimethyl acetal gave, generally in high yield, a series of sym-2-dimethylaminomethylene-1,3-diones which reacted with phenylhydrazine and methylhydrazine to afford, generally in satisfactory yield, a number of 1,5-disubstituted 4-acylpyrazoles. The applications and limits of this new pyrazole synthesis are presented and discussed. 相似文献
179.
Robert F. Hout William J. Pietro Warren J. Hehre 《Journal of computational chemistry》1983,4(2):276-282
A scheme is presented that enables photographic representation of the (two-dimensional) surfaces of (three-dimensional) molecular orbitals and electron density functions. The algorithm has been implemented by a program which is completely general and computationally efficient. 相似文献
180.
The potential surfaces of pyrazine, 4-nitropyridine, 1,2-, 1,3-, 1,4- dicyanobenzene radical anions have been calculated within theab initio and electrostatic molecular potential formalism, including the effect of the solvent. These potential surfaces suggest models of ion pairs with alkali cations, which are in agreement with those deduced from related ESR spectra. 相似文献