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141.
Elvira Vidović Doris Klee Hartwig Höcker 《Journal of polymer science. Part A, Polymer chemistry》2007,45(19):4536-4544
Poly(D ,L ‐lactide) and poly(D ,L ‐lactide‐co‐glycolide) with various composition and with one methacrylate and one carboxylate end group were synthesized and grafted onto poly(vinyl alcohol) (PVA) via the carboxylate group. The graft copolymers were crosslinked via the methacrylate groups using a free radical initiator. The polymer networks were characterized by means of NMR and studied qualitatively by means of IR spectroscopy. The influence of the glycolide content in the polyester grafts and of the number of ester units in the grafts on thermal properties and swellability were studied as well. The high swellability in water is characteristic of all hydrogels. Differential scanning calorimetry (DSC) showed a single glass transition temperature that occurs in the range between 51 and 69 °C. Thermogravimetric analysis (TGA) of the networks showed the main loss in weight in the temperature range between 290 and 370 °C. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4536–4544, 2007 相似文献
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145.
W. v. Moraczewski 《Analytical and bioanalytical chemistry》1909,48(12):788-789
146.
M. Lugo-Licona J. Miranda C. M. Romo-Kröger 《Journal of Radioanalytical and Nuclear Chemistry》2004,262(2):391-401
The production cross sections of L-shell X-ray of some rare earth elements have been measured by collision of 12C4+ and 16O4+ ions of 0.5 to 0.75 MeV/amu. The results were compared with experimental data of other authors and with theoretical predictions
gained by the ECPSSR and ECPSSR plus multiple ionization (ECPSSR+MI) models. For atomic parameters (fluorescence yields and
probabilities for Coster-Kronig transitions) the role of several databases were studied. The ECPSSR theory underestimates
cross sections when compared with experimental results obtained in the present work, but ECPSSR+MI has a better agreement
with the experimental data.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
147.
A. v. Braunmühl 《Mathematische Annalen》1882,20(4):557-586
Ohne ZusammenfassungMit einer lithogr. Tafel. 相似文献
148.
F. v. Arlt 《Monatshefte für Chemie / Chemical Monthly》1901,20(5):425-449
Ohne ZusammenfassungEs sei mir gestattet, auch an dieser Stelle meinem hochverehrten Lehrer, Herrn Prof. Dr. Zd. H. Skraup, für das während meiner ganzen Studienzeit mir entgegengebrachte Interesse und Wohlwollen, sowie ganz besonders für die Unterstützung und Förderung bei Ausarbeitung der vorliegenden Dissertation herzlich und aufrichtig zu danken. 相似文献
149.
Wolfgang A Herrmann Karl Öfele Denise v. Preysing Sabine K Schneider 《Journal of organometallic chemistry》2003,687(2):229-248
Due to the great importance of palladium-catalyzed Heck-type reactions in scientific and industrial chemistry, a lot of publications and reviews have been published during the last years describing this matter under different aspects. This article presents a summary of catalytic applications of palladium complexes with phosphorus ligands containing a metallated sp3-carbon centre (“palladacycles”) or with N-heterocyclic carbene ligands in C-C and C-N coupling reactions of aryl halides including recent results of mechanistic discussions about their role in the catalytic cycle. 相似文献
150.
The final state of Au+Au collisions at √s=130 AGeV at RHIC has been reconstructed within the framework of the Buda-Lund hydrodynamical model, by performing a simultaneous fit to final data on twoparticle Bose-Einstein correlations of the STAR and PHENIX Collaboration, and final identified single-particle spectra as measured by the PHENIX Collaboration. The results indicate a strongly three dimensional expansion, with a four-velocity field that is almost a spherically symmetric Hubble flow. We find large transverse geometrical source sizes, R G=9.8±1.2 fm, relatively short mean freeze-out time, τ0=6.1±0.3 fm/c and a short duration of particle emission, Δτ=0.02±1.5 fm/c. Most strikingsly, we find an indication for a hot central part of the hydrodynamically evolving core, characterized by a central temperature T 0=202±13 MeV that is close to (or even above) the deconfinement temperature of the quark-hadron phase transition. The best fit indicates a cold surface temperature T s=110±16 MeV. When the possibility of the hot center is excluded, the confidence level of the fit decreases from 28.9% to 1.0%. Predictions are made for the rapidity dependence of the slope parameters and for the transverse mass depedence of the rapidity width of the single-particle spectra, and the transverse mass dependence of the non-identical particle correlations. 相似文献