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21.
Tagouegni Senghor Fotsa-Ngaffo Fernande Kenfack-Jiotsa Aurélien 《Optical and Quantum Electronics》2022,54(3):1-57
Optical and Quantum Electronics - In the past few decades, the academic research and industrial synergy is dramatically accelerating to conceptualize high data rate services. The congestion in the... 相似文献
22.
23.
Dr. Mara Beltrán-Gastélum Dr. Berta Esteban-Fernández de Ávila Dr. Hua Gong Dr. Pooyath Lekshmy Venugopalan Prof. Dr. Tibor Hianik Prof. Dr. Joseph Wang Veronika Subjakova 《Chemphyschem》2019,20(23):3177-3180
Herein, we report ultrasound-propelled graphene-oxide coated gold nanowire motors, functionalized with fluorescein-labeled DNA aptamers (FAM-AIB1-apt), for qualitative detection of overexpressed AIB1 oncoproteins in MCF-7 breast cancer cells. The movement of nanomotors under the ultrasound field facilitated intracellular uptake and resulted in a faster aptamer binding with the target protein and thus faster fluorescence recovery. The propulsion behavior of the aptamer functionalized nanomotors greatly enhanced the fluorescence intensity compared to static conditions. The new aptamer@nanomotor-based strategy offers considerable potential for further development of sensing methodologies towards diagnosis of breast cancer. 相似文献
24.
Di Turo Francesca Parra Rafael Piquero-Cilla Joan Favero Gabriele Doménech-Carbó Antonio 《Journal of Solid State Electrochemistry》2019,23(3):771-781
Journal of Solid State Electrochemistry - Electrochemical impedance spectroscopy (EIS) and voltammetry of immobilized particles (VIMP) measurements using air-saturated mineral water and... 相似文献
25.
Kumar Mahesh Reddy G. Janardhana Bég O. Anwar 《Journal of Thermal Analysis and Calorimetry》2019,138(1):531-543
Journal of Thermal Analysis and Calorimetry - This article studies the pattern of heat lines in free convection non-Newtonian flow from a semi-infinite vertical cylinder via Bejan’s heat... 相似文献
26.
Samia Amara Joël Toulc'Hoat Laure Timperman Agnès Biller Hervé Galiano Corinne Marcel Matthieu Ledigabel Prof. Mérièm Anouti 《Chemphyschem》2019,20(4):581-594
The development of a suitable functional electrolyte is urgently required for fast-charging and high-voltage alkali-ion (Li, Na, K) batteries as well as next-generation hybrids supercapacitors. Many recent works focused on an optimal selection of electrolytes for alkali-ion based systems and their electrochemical performance but the understanding of the fundamental aspect that explains their different behaviour is rare. Herein, we report a comparative study of transport properties for LiPF6, NaPF6, KPF6 in acetonitrile (AN) and a binary mixture of ethylene carbonate (EC), dimethyl carbonate (DMC): (EC/DMC : 1/1, weigh) through conductivities, densities and viscosities measurements in wide temperature domain. By application of the Stokes-Einstein, Nernst-Einstein, and Jones Dole equations, the effective ionic solvated radius of cation (reff), the ionic dissociation coefficient (αD) and structuring Jones Dole's parameters (A, B) for salt are calculated and discussed according to solvent or cation nature as a function of temperature. From the results, we demonstrate that better mobility of potassium can be explained by the nature of the ion-ion and ion-solvent interactions due to its polarizability. In the same time, the predominance of triple ions in the case of K+, is a disadvantage at high concentration. 相似文献
27.
Dr. Silvia Castro-Fernández Carlos M. Cruz Dr. Inês F. A. Mariz Dr. Irene R. Márquez Vicente G. Jiménez Lucía Palomino-Ruiz Prof. Juan M. Cuerva Dr. Ermelinda Maçôas Dr. Araceli G. Campaña 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7205-7211
A new family of distorted ribbon-shaped nanographenes was designed, synthesized, and their optical and electrochemical properties were evaluated, pointing out an unprecedented correlation between their structural characteristics and the two-photon absorption (TPA) responses and electrochemical band gaps. Three nanographene ribbons have been prepared: a seven-membered-ring-containing nanographene presenting a tropone moiety at the edge, its full-carbon analogue, and a purely hexagonal one. We have found that the TPA cross-sections and the electrochemical band gaps of the seven-membered-ring-containing compounds are higher and lower, respectively, than those of the fully hexagonal polycyclic aromatic hydrocarbon (PAH). Interestingly, the inclusion of additional curvature has a positive effect in terms of non-linear optical properties of those ribbons. 相似文献
28.
Carla Alice Carabet Anca Moan Ion Plrie Gabriela Iacobescu Andrei Rotaru Marian Leulescu Mariana Popescu Petre Rotaru 《Molecules (Basel, Switzerland)》2020,25(23)
Two yellow bis-azo dyes containing anthracene and two azodiphenylether groups (BPA and BTA) were prepared, and an extensive investigation of their physical, thermal and biological properties was carried out. The chemical structure was confirmed by the FTIR spectra, while from the UV–Vis spectra, the quantum efficiency of the laser fluorescence at the 476.5 nm was determined to be 0.33 (BPA) and 0.50 (BTA). The possible transitions between the energy levels of the electrons of the chemical elements were established, identifying the energies and the electronic configurations of the levels of transition. Both crystals are anisotropic, the optical phenomenon of double refraction of polarized light (birefringence) taking place. Images of maximum illumination and extinction were recorded when the crystals of the bis-azo compounds rotated by 90° each, which confirms their birefringence. A morphologic study of the thin films deposited onto glass surfaces was performed, proving the good adhesion of both dyes. By thermal analysis and calorimetry, the melting temperatures were determined (~224–225 °C for both of them), as well as their decomposition pathways and thermal effects (enthalpy variations during undergoing processes); thus, good thermal stability was exhibited. The interaction of the two compounds with collagen in the suede was studied, as well as their antioxidant activity, advocating for good chemical stability and potential to be safely used as coloring agents in the food industry. 相似文献
29.
The gauge symmetry group of any slave boson representation allows to gauge away the phase of bosonic fields. One benefit of this radial field formulation is the elimination of spurious Bose condensations when saddle-point approximation is performed. Within the Kotliar–Ruckenstein representation, three of the four bosonic fields can be radial while the last one has to remain complex. In this work, the procedure to carry out the functional integration involving constrained fermionic fields, complex bosonic fields, and radial bosonic fields is presented. The correctness of the representation is verified by exactly evaluating the partition function and the Green's function of the Hubbard model in the atomic limit. 相似文献
30.
Z. Hadjou Bélaid S. Ben Mansour D. Boroguiaa A. Boubris L. Benhabib F. Z. Benkhaled 《Journal of Macromolecular Science: Physics》2020,59(11):686-696
AbstractThis work examines the development and characterization of tripropylene glycol di-acrylate/liquid crystal E7 (TPGDA/LC E7) PDLCs composite materials (polymer-dispersed-liquid-crystals). These systems were produced by UV irradiation photopolymerization (PIPS) of a mixture of the monomer tripropylene glycol di-acrylate (TPGDA) and the liquid crystal E7 (LC E7, a mixture of three cyano-biphenyl and one cyano-terphenyl LCs), in the presence of 2?wt% (of the acrylate/E7 mixture) of a photoinitiator. Electro-optical, thermal and optical characterization was used to understand the effect of the LC concentration on the electro-optical and thermo-physical properties of these materials. Polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) studies were performed to observe the system morphology and to determine the transition temperatures of these materials, both as a function of their composition. The findings showed a slight variation of the nematic-isotropic transition temperature, TNI, of the LC E7 and of the glass transition temperature, Tg, of the TPGDA polymeric matrix as a function of the mass percentage of the LC E7. A very good electro-optical response for the composition 30/70?wt % TPGDA/LC E7 was obtained. 相似文献