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101.
The interaction between two optical vortex solitons (OVS), formed on different background beams is analyzed numerically. Analogous to the one-dimensional case, vector OVS seem obtainable [12]. The relative topological charges of the interacting (off-axis) vortices are found to rule their propagation characteristics. Attraction is found in the case of equal charges, in contrast to the opposite case, where repulsion is present. 相似文献
102.
A. Dreischuh I. Buchvarov E. Eugenieva S. Dinev V. Marinov 《Optical and Quantum Electronics》1996,28(9):1187-1197
A method for ultrashort pulse-duration measurement is analysed both theoretically and experimentally. The approach is based on a time-resolved induced phase modulation of a probe beam-pulse in a two-colour Z-scan configuration. The experimental results presented are in good agreement with the simple analytical result derived for retrieving unknown pulse width. 相似文献
103.
Matthias Weil PD Dr. Dietrich K. Breitinger Günther Liehr Jürgen Zürbig 《无机化学与普通化学杂志》2007,633(3):429-434
The crystal structures of (NH4)[HgSO3Cl] ( 1 ) and of (NH4)2[Hg(SO3)2] ( 2 ) were determined from single crystal diffractometer data sets. 1 : 22 °C, Pnma, Z = 4, a = 15.430(3), b = 5.525(1), c = 6.679(1) Å, R(F) = 0.0256, Rw(F2) = 0.0642 (all 1056 unique reflections). 2 : ?108 °C, P212121, Z = 4, a = 6.2240(4), b = 9.3908(6), c = 13.6110(8) Å, R(F) = 0.0179, Rw(F2) = 0.0493 (all 2699 unique reflections). The structure of 1 contains bent Cl‐Hg‐SO3 entities (site symmetry m; d(Hg‐Cl) = 2.3403(13) Å, d(Hg‐S) = 2.3636(12) Å, ∠(Cl‐Hg‐S) = 164.51(5)°, d(S‐O) 2×1.458(3) Å, 1.468(4) Å, = 1.461Å) linked to undulated ribbons parallel to the b ‐axis by intermolecular secondary bonds SO···Hg (d(O···Hg) = 2×2.595(3) Å). These ribbons in turn aggregate to layers around the bc ‐plane. The layers are stacked along the a ‐axis with interlayer distances of a /2. The structure of 2 is made up of O3S‐Hg‐SO3 moieties (d(Hg‐S) = 2.3935(7), 2.3935(8) Å; ∠(Hg‐S‐Hg) = 174.41(3)°; = 1.474Å), that are linked to ribbons parallel to the a axis by coordination of Hg to three remote O atoms (2.801(4) < d(Hg‐O) < 2.844(3) Å). Adjacent ribbons are joined together by an additional Hg‐O contact of 2.733(3) Å, leading to a three‐dimensional anionic framework. Both crystal structures are stabilised by disordered NH4+ cations, placed between the anionic layers or in the vacancies of the framework, via moderate hydrogen bonding interactions N‐H···O with donor‐acceptor distances ranging from 2.8 to 3.2Å. 1 and 2 were further characterised by thermal analysis (TG, DSC). They start to decompose at temperatures above 130 °C. 相似文献
104.
105.
Prof. Dr. Lena Keller Dr. Emilia Oueis Dr. Amninder Kaur Dr. Nasim Safaei Dr. Susanne H. Kirsch Dr. Antonia P. Gunesch Dr. Sibylle Haid Dr. Ulfert Rand Prof. Dr. Luka Čičin-Šain Dr. Chengzhang Fu PD Dr. Joachim Wink Prof. Dr. Thomas Pietschmann Prof. Dr. Rolf Müller 《Angewandte Chemie (International ed. in English)》2023,62(6):e202214595
A new family of highly unusual sesquarterpenoids (persicamidines A–E) exhibiting significant antiviral activity was isolated from a newly discovered actinobacterial strain, Kibdelosporangium persicum sp. nov., collected from a hot desert in Iran. Extensive NMR analysis unraveled a hexacyclic terpenoid molecule with a modified sugar moiety on one side and a highly unusual isourea moiety fused to the terpenoid structure. The structures of the five analogues differed only in the aminoalkyl side chain attached to the isourea moiety. Persicamidines A–E showed potent activity against hCoV-229E and SARS-CoV-2 viruses in the nanomolar range together with very good selectivity indices, making persicamidines promising as starting points for drug development. 相似文献