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1.
Synthesis,Electronic Properties and WOLED Devices of Planar Phosphorus‐Containing Polycyclic Aromatic Hydrocarbons 下载免费PDF全文
Dr. François Riobé Rózsa Szűcs Dr. Pierre‐Antoine Bouit Dr. Denis Tondelier Bernard Geffroy Fátima Aparicio Julia Buendía Prof. Luis Sánchez Prof. Régis Réau Prof. László Nyulászi Prof. Muriel Hissler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6547-6556
We describe the synthesis and the physical properties of polyaromatic hydrocarbons (PAHs) containing a phosphorus atom at the edge. In particular, the impact of the successive addition of aromatic rings on the electronic properties was investigated by experimental (UV/Vis absorption, fluorescence, cyclic voltammetry) and theoretical studies (DFT). The physical properties recorded in solution and in the solid state showed that the P‐containing PAHs exhibit properties expected for an emitter in white organic light‐emitting diodes (WOLEDs). 相似文献
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Nonlinear Dynamics - In this paper, the dynamical similarity of multi-block catenary arches and columns is discussed, which can be used for the simplified design of rocking arches. The basic... 相似文献
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Predoana Luminita Atkinson Irina Karaj Dániel Attila Odhiambo Vincent Otieno Bakos László Péter Nagyné Kovács Teodóra Pandele-Cusu Jeanina Petrescu Simona Rusu Adriana Szilágyi Imre M. Pokol György Zaharescu Maria 《Journal of Thermal Analysis and Calorimetry》2021,143(4):2893-2900
Journal of Thermal Analysis and Calorimetry - In the literature data, several papers reported the synthesis by various chemical or physical methods of the SrCu2O2 (SCO) having possible applications... 相似文献
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Contrary to the expectation arising from the tanglegram Kuratowski theorem of Czabarka et al. (SIAM J. Discrete Math. 31(3), 1732–1750, 2017), we construct an infinite antichain of planar tanglegrams with respect to the induced subtanglegram partial order. R.E. Tarjan, R. Laver, D.A. Spielman and M. Bóna, and possibly others, showed that the partially ordered set of finite permutations ordered by deletion of entries contains an infinite antichain, i.e., there exists an infinite collection of permutations, such that none of them contains another as a pattern. Our construction adds a twist to the construction of Spielman and Bóna (Electr. J. Comb. 7, N2, 2000).
相似文献8.
Energetic 2,2‐Dimethyltriazanium Salts: A New Family of Nitrogen‐Rich Hydrazine Derivatives 下载免费PDF全文
Dr. Valérian Forquet Dr. Carlos Miró Sabaté Dr. Guy Jacob Dr. Yann Guelou Dr. Henri Delalu Dr. Chaza Darwich 《化学:亚洲杂志》2015,10(8):1668-1675
Amination of 1,1‐dimethylhydrazine with NH2Cl or hydroxylamine‐O‐sulfonic acid yields 2,2‐dimethyltriazanium (DMTZ) chloride ( 3 ) and sulphate ( 4 ), respectively. The DMTZ cation was paired with the nitrogen‐rich anions 5‐aminotetrazolate ( 5 ), 5‐nitrotetrazolate ( 6 ), 5,5′‐azobistetrazolate ( 7 ), and azide ( 8 ), yielding a new family of energetic salts. The synthesis was carried out by metathesis reactions of salts 3 or 4 and a suitable silver or barium salt. To minimize the risks involved when using heavy metal salts, we used electrodialysis for the synthesis of azide 8 , which avoids the use of highly sensitive species. The DMTZ derivatives were characterized by IR and multinuclear NMR spectroscopy, elemental analysis, and X‐ray diffraction. Thermal stabilities were measured using DSC analysis and their sensitivities towards classical stimuli were determined using standard tests. Lastly, the relationship between hydrogen bonding in the solid state and sensitivity is discussed. 相似文献
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Fanni Bede Prof. Dr. László Kollár Dr. Nándor Lambert Prof. Dr. Péter Huszthy Dr. Péter Pongrácz 《European journal of organic chemistry》2023,26(31):e202300571
Palladium-catalyzed hydroaminocarbonylation reactions of olefins using aliphatic amines were performed under carbon monoxide atmosphere. Despite the strong basicity of the applied nucleophiles, the targeted amides were successfully synthesized in the absence of acidic additives. Styrene, oct-1-ene and isoprene were transformed to the corresponding amide isomers in moderate to good isolated yields under optimized reaction conditions. Various aliphatic amines were used as N-nucleophiles. The effect of chiral diphosphines on product distribution, that is, on chemo-, regio- and enantioselectivities was also studied. Plausible explanation was given for the additive-free hydroaminocarbonylation reaction. 相似文献
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Thermal Effects and Structural Changes of Photosynthetic Reaction Centers Characterized by Wide Frequency Band Hydrophone: Effects of Carotenoids and Terbutryn 下载免费PDF全文
László Nagy Vladimir Kiss Vlad Brumfeld Károly Osvay Ádám Börzsönyi Melinda Magyar Tibor Szabó Márta Dorogi Shmuel Malkin 《Photochemistry and photobiology》2015,91(6):1368-1375
Photothermal characteristics and light‐induced structural (volume) changes of carotenoid‐containing and noncontaining photosynthetic reaction centers (RCs) were investigated by wide frequency band hydrophone. We found that the presence of carotenoid either does not play considerable role in the light‐induced conformational movements, or these rearrangements are too slow for inducing a photoacoustic (PA) signal. The kinetic component with a few tens of microseconds, exhibited by the carotenoid‐less RCs, appears to be similar to that of triplet state lifetimes, identified by other methods. The binding of terbutryn to the acceptor side is shown to affect the dynamics of the RC. Our results do not confirm large displacements or volume changes induced by the charge movements and by the charge relaxation processes in the RCs in few hundreds of microseconds time scale that accompanies the electron transfer between the primary and secondary electron acceptor quinones. 相似文献