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51.
Carolina Toloza Porras Dagmar R. D'hooge Paul H. M. Van Steenberge Marie‐Françoise Reyniers Guy B. Marin 《大分子反应工程》2013,7(7):311-326
Kinetic Monte Carlo simulations are performed to investigate the capability of ICAR ATRP for the synthesis of well‐defined poly(isobornyl acrylate‐b‐styrene) block(‐like) copolymers using one‐pot semi‐batch and two‐pot batch procedures. The block copolymer quality is quantified via a block deviation (〈BD〉) value. For 〈BD〉 values lower than 0.30, the quality is defined as good and for well‐chosen polymerization conditions the formation of homopolymer chains upon addition of the second monomer can be suppressed. A better block quality is obtained when isobornyl acrylate is polymerized first. For lower Cu levels a one‐pot semi‐batch procedure allows a much faster ATRP and better control over the polymer properties than a two‐pot batch procedure.
52.
Andreas Loos 《Physik in unserer Zeit》2017,48(5):257-257
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Using instrumental neutron activation analysis 18 elements are determined in 9 standard rocks of the central geological institut
of the GDR. The results are compared with certified values.
相似文献
57.
We consider the capacity of classical information transfer for noiseless quantum channels carrying a finite average number of massive bosons and fermions. The maximum capacity is attained by transferring the Fock states generated from the grand-canonical ensemble. Interestingly, the channel capacity for a Bose gas indicates the onset of Bose-Einstein condensation, by changing its qualitative behavior at the criticality, while for a channel carrying weakly attractive fermions, it exhibits the signatures of Bardeen-Cooper-Schrieffer transition. We also show that, for noninteracting particles, fermions are better carriers of information than bosons. 相似文献
58.
We tell the tale of the first writing of a partial transpose, without guaranteeing historical authenticity.
Dedicated to Prof. Asher Peres, Haifa, on the occasion of his 70th birthday. 相似文献
59.
The construction of the three-layer hybrid local self-consistent field/molecular mechanics/self-consistent reaction field method is detailed. This method is specifically devoted to the study of the reactivity of large chemical systems in solution. The solvent, modeled by a polarizable continuum, surrounds the whole solute molecule. Solute–solvent interactions are taken into account by means of the self-consistent reaction field approach. The solute system is treated by both quantum and molecular mechanics, the former being principally applied to the reactive part, i.e., the part undertaking bond forming or breaking, the latter being reserved for the ancillary encumbering groups. The connection between the molecular mechanics and the quantum mechanics part is accomplished by a strictly localized bond orbital that remains frozen within the local self-consistent field framework. As a test system, the asymmetric Diels–Alder reaction between cyclopentadiene and (–)-menthyl acrylate is studied for the first time with steric interactions and electrostatic solvent effects taken into account simultaneously. The results indicate that the coupling of both interactions leads to conclusions that could not have been guessed from separate calculations.Proceedings of the 11th International Congress of Quantum chemistry satellite meeting in honour of Jean-Louis Rivail 相似文献
60.
Yu LH DiMauro L Doyuran A Graves WS Johnson ED Heese R Krinsky S Loos H Murphy JB Rakowsky G Rose J Shaftan T Sheehy B Skaritka J Wang XJ Wu Z 《Physical review letters》2003,91(7):074801
We report the first experimental results on a high-gain harmonic-generation (HGHG) free-electron laser (FEL) operating in the ultraviolet. An 800 nm seed from a Ti:sapphire laser has been used to produce saturated amplified radiation at the 266 nm third harmonic. The results confirm the predictions for HGHG FEL operation: stable central wavelength, narrow bandwidth, and small pulse-energy fluctuation. 相似文献