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71.
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A.A. Kontogeorgos D.P. Korfiatis K.A.Th. Thoma J.C. Vardaxoglou 《Optics and Lasers in Engineering》2009,47(11):1195-1198
Selective illumination of a silicon wafer can be used for the construction of non-permanent inductive grids. A numerical model is used for the calculation of plasma density distribution in silicon as a function of time. Some indicative results on the microwave properties of the device are presented. 相似文献
74.
S. J. Picken W. H. de Jeu W. F. van Gunsteren P. Th. van Duijnen W. H. de Jeu 《Liquid crystals》2013,40(11-12):1359-1371
A Commentary on the paper ”A molecular dynamics study of the nematic phase of 4‐n‐pentyl‐4′‐cyanobiphenyl?, by S. J. Picken, W. F. van Gunsteren, P. Th. van Duijnen and W. H. de Jeu. First published in Liquid Crystals, 6, 357‐371 (1989). 相似文献
75.
Jan Rosenboom Dr. Lukas Chojetzki Dr. Tim Suhrbier Dr. Jabor Rabeah Dr. Alexander Villinger Dr. Ronald Wustrack Dr. Jonas Bresien Prof. Dr. Axel Schulz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(36):e202200624
The activation of C−Br bonds in various bromoalkanes by the biradical [⋅P(μ-NTer)2P⋅] ( 1 ) (Ter=2,6-bis-(2,4,6-trimethylphenyl)-phenyl) is reported, yielding trans-addition products of the type [Br−P(μ-NTer)2P−R] ( 2 ), so-called 1,3-substituted cyclo-1,3-diphospha-2,4-diazanes. This addition reaction, which represents a new easy approach to asymmetrically substituted cyclo-1,3-diphospha-2,4-diazanes, was investigated mechanistically by different spectroscopic methods (NMR, EPR, IR, Raman); the results suggested a stepwise radical reaction mechanism, as evidenced by the in-situ detection of the phosphorus-centered monoradical [⋅P(μ-NTer)2P-R].< To provide further evidence for the radical mechanism, [⋅P(μ-NTer)2P-Et] ( 3Et ⋅) was synthesized directly by reduction of the bromoethane addition product [Br-P(μ-NTer)2P-Et] ( 2 a ) with magnesium, resulting in the formation of the persistent phosphorus-centered monoradical [⋅P(μ-NTer)2P-Et], which could be isolated and fully characterized, including single-crystal X-ray diffraction. Comparison of the EPR spectrum of the radical intermediate in the addition reaction with that of the synthesized new [⋅P(μ-NTer)2P-Et] radical clearly proves the existence of radicals over the course of the reaction of biradical [⋅P(μ-NTer)2P⋅] ( 1 ) with bromoethane. Extensive DFT and coupled cluster calculations corroborate the experimental data for a radical mechanism in the reaction of biradical [⋅P(μ-NTer)2P⋅] with EtBr. In the field of hetero-cyclobutane-1,3-diyls, the demonstration of a stepwise radical reaction represents a new aspect and closes the gap between P-centered biradicals and P-centered monoradicals in terms of radical reactivity. 相似文献
76.
Jahnke T Czasch A Schöffler M Schössler S Käsz M Titze J Kreidi K Grisenti RE Staudte A Jagutzki O Schmidt LP Weber T Schmidt-Böcking H Ueda K Dörner R 《Physical review letters》2007,99(15):153401
We investigate the interatomic Coulombic decay (ICD) of neon dimers following photoionization with simultaneous excitation of the ionized atom (shakeup) in a multiparticle coincidence experiment. We find that, depending on the parity of the excited state, which determines whether ICD takes place via virtual dipole photon emission or overlap of the wave functions, the decay happens at different internuclear distances, illustrating that nuclear dynamics heavily influence the electronic decay in the neon dimer. 相似文献
77.
We evaluate the N to Delta axial transition form factors in lattice QCD with no dynamical sea quarks, with two degenerate flavors of dynamical Wilson quarks, and using domain wall valence fermions with three flavors of staggered sea quarks. We predict the ratio C(5)(A)(q(2))/C(3)(V)(q(2)) relevant for parity violating asymmetry experiments and verify the off-diagonal Goldberger-Treiman relation. 相似文献
78.
Renault A Kandula DZ Witte S Wolf AL Zinkstok RT Hogervorst W Eikema KS 《Optics letters》2007,32(16):2363-2365
The phase stability of broadband (280 nm bandwidth) terawatt-class parametric amplification was measured, for the first time to our knowledge, with a combination of spatial and spectral interferometry. Measurements at four different wavelengths from 750 to 900 nm were performed in combination with numerical modeling. The phase stability is better than 1/23 rms of an optical cycle for all the measured wavelengths, depending on the phase-matching conditions in the amplifier. 相似文献
79.
80.
Teresa Ksel Gran Schulz Gerald Drger Andreas Kirschning 《Angewandte Chemie (International ed. in English)》2020,59(30):12376-12380
This report discloses the photochemical homolytic cleavage of iodine azide after its formation following release from polymer‐bound bisazido iodate(I) anions. A series of radical reactions are reported including the 1,2‐functionlization of alkenes and the unprecedented chemoselective oxidation of secondary alcohols in the presence of primary alcohols. 相似文献