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91.
Hélène Beucher Dr. Sudhir Kumar Dr. Roopender Kumar Dr. Estíbaliz Merino Wei-Hsu Hu Gerrit Stemmler Sergio Cuesta-Galisteo Dr. Jorge A. González Léonard Bezinge Dr. Jakub Jagielski Dr. Chih-Jen Shih Prof. Dr. Cristina Nevado 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17604-17612
Efficient OLED devices have been fabricated using organometallic complexes of platinum group metals. Still, the high material cost and low stability represent central challenges for their application in commercial display technologies. Based on its innate stability, gold(III) complexes are emerging as promising candidates for high-performance OLEDs. Here, a series of alkynyl-, N-heterocyclic carbene (NHC)- and aryl-gold(III) complexes stabilized by a κ3-(N^C^C) template have been prepared and their photophysical properties have been characterized in detail. These compounds exhibit good photoluminescence quantum efficiency (ηPL) of up to 33 %. The PL emission can be tuned from sky-blue to yellowish green colors by variations on both the ancillary ligands as well as on the pincer template. Further, solution-processable OLED devices based on some of these complexes display remarkable emissive properties (ηCE 46.6 cd.A−1 and ηext 14.0 %), thus showcasing the potential of these motifs for the low-cost fabrication of display and illumination technologies. 相似文献
92.
Marisa C. Oliveira Renan A. P. Ribeiro Elson Longo Mauricio R. D. Bomio Sergio R. de Lázaro 《International journal of quantum chemistry》2020,120(22):e26368
The structural, electronic, and vibrational properties of two leading representatives of the Zn-based spinel oxides class, normal ZnX2O4 (X = Al, Ga, In) and inverse Zn2MO4 (M = Si, Ge, Sn) crystals, were investigated. In particular, density functional theory (DFT) was combined with different exchange-correlation functionals: B3LYP, HSE06, PBE0, and PBESol. Our calculations showed good agreement with the available experimental data, showing a mean percentage error close to 3% for structural parameters. For the electronic structure, the obtained HSE06 band-gap values overcome previous theoretical results, exhibiting a mean percentage error smaller than 10.0%. In particular, the vibrational properties identify the significant differences between normal and inverse spinel configurations, offering compelling evidence of a structure-property relationship for the investigated materials. Therefore, the combined results confirm that the range-separated HSE06 hybrid functional performs the best in spinel oxides. Despite some points that cannot be directly compared to experimental results, we expect that future experimental work can confirm our predictions, thus opening a new avenue for understanding the structural, electronic, and vibrational properties in spinel oxides. 相似文献
93.
Mejía Hugo Fernando Giraldo Jiménez-Piqué Emilio Valdés Matías Procaccini Raúl Pellice Sergio 《Journal of Solid State Electrochemistry》2020,24(10):2451-2460
Journal of Solid State Electrochemistry - A novel material was developed using sol-gel chemistry and an environmental-friendly grafting process of clay nanoparticles. In a previous work of our... 相似文献
94.
Juan A. Allegretto Agustín Iborra Dr. Juan M. Giussi Dr. Catalina von Bilderling Dr. Marcelo Ceolín Dr. Sergio Moya Dr. Omar Azzaroni Dr. Matias Rafti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(54):12388-12396
This work reports on a novel and versatile approach to control the structure of metal–organic framework (MOFs) films by using polymeric brushes as 3D primers, suitable for triggering heterogeneous MOF nucleation. As a proof-of-concept, this work explores the use of poly(1-vinylimidazole) brushes primer obtained via surface-initiated atom transfer radical polymerization (SI-ATRP) for the synthesis of Zn-based ZIF-8 MOF films. By modifying the grafting density of the brushes, smooth porous films were obtained featuring inherently hydrophobic microporosity arising from ZIF-8 structure, and an additional constructional interparticle mesoporosity, which can be employed for differential adsorption of targeted adsorbates. It was found that the grafting density modulates the constructional porosity of the films obtained; higher grafting densities result in more compact structures, while lower grafting density generates increasingly inhomogeneous films with a higher proportion of interparticle constructional porosity. 相似文献
95.
Erika Alejandra Martínez-Ortega José Sergio López-Briones Gabriela Rodríguez-Hernández Ricardo Ernesto Ramírez-Orozco 《Natural product research》2020,34(18):2639-2641
AbstractThe objective of this study was to evaluate the antimicrobial effect of Agave fructans against the Salmonella Typhimurium in “in vitro” experiments. The result of the antimicrobial activity was 263.89?±?0, 414.95?±?12.83, 494.54?±?13.88, 522.29?±?0, 580.41?±?14.92?AU for 10, 20, 30, 40 and 50% of Agave fructans (AF) respectively. In addition, there is a significant effect on the growth of the bacteria with all the percentages of AF evaluated (p?<?0.001, R2?=?0.859) with respect to the control. The growth rate of Salmonella with 25% AF was statistically significant compared to the control (?0.7353?±?0.586, 0.0079?±?0.002?D.O./h, respectively; p?>?0.01). Agave fructans could be an alternative to prevent the infections caused by Salmonella. 相似文献
96.
Riisager K. Borge M. J. G. Briz J. A. Carmona-Gallardo M. Forstner O. Fraile L. M. Fynbo H. O. U. Camacho A. Garzon Johansen J. G. Jonson B. Lund M. V. Lachner J. Madurga M. Merchel S. Nacher E. Nilsson T. Steier P. Tengblad O. Vedia V. 《The European Physical Journal A - Hadrons and Nuclei》2020,56(3):1-19
The European Physical Journal A - A deterministic treatment of sequential neutron emission, based on recursive equations of the residual temperatures, was applied to numerous fission cases (i.e. 49... 相似文献
97.
98.
Nonlinear Dynamics - In this paper, type V intermittency is studied using the M function methodology developed in the last years. This methodology is applied on two different maps to evaluate the... 相似文献
99.
We consider quantum field theoretical models inn dimensional space-time given by interaction densities which are bounded functions of an ultraviolet cut-off boson field. Using methods of euclidean Markov field theory and of classical statistical mechanics, we construct the infinite volume imaginary and real time Wightman functions as limits of the corresponding quantities for the space cut-off models. In the physical Hilbert space, the space-time translations are represented by strongly continuous unitary groups and the generator of time translationsH is positive and has a unique, simple lowest eigenvalue zero, with eigenvector , which is the unique state invariant under space-time translations. The imaginary time Wightman functions and the infinite volume vacuum energy density are given as analytic functions of the coupling constant. The Wightman functions have cluster properties also with respect to space translations. 相似文献
100.
Sergio Albeverio Raphael Høegh-krohn 《Journal of Mathematical Analysis and Applications》1984,101(2):491-513
Schrödinger operators on L2(3) of the form ?Δ + Vλ with potentials Vλ real-analytic in λ are discussed. The analytic structure in Vλ and k (with k2 the energy variable) of the resolvent kernel, the eigenvalues and resonances is exhibited and we obtain in particular convergent perturbation expansions for the resonances and the corresponding resonance functions. The lower order expansion coefficients are computed explicitly. The resonances and the corresponding functions are also computed for a particle moving under the action of n point interactions. This gives asymptotic low energy information about Schrödinger Hamiltonians with short range potentials. The perturbation theory of resonances, eigenvalues and of the corresponding functions for Hamiltonians describing n point interactions perturbed by a potential is also given. 相似文献