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71.
Chiguils-Prez Yureli Rodrguez-Hurtado Alejandro Israel Prez-Picaso Lemuel Ramrez-Marroqun Oscar Abelardo Martnez-Pascual Roxana Hernndez-Nez Emanuel Vias-Bravo Omar Lpez-Torres Adolfo 《Russian Journal of General Chemistry》2022,91(1):S123-S130
Russian Journal of General Chemistry - Herein, the synthesis of six new derivatives via molecular hybridization of imidazole or triazole and valine methyl ester as a rational design for accessing... 相似文献
72.
Alzate Manuela Gamba Oscar Daza Carlos Santamaria Alexander Gallego Jaime 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12355-12363
Journal of Thermal Analysis and Calorimetry - Nanomaterials and nanocomposites have gained relevance in science and technology due to their excellent properties. Therefore, the characterization of... 相似文献
73.
Dr. Nataliia S. Kariaka Dr. Victor A. Trush Dr. Viktoriya V. Dyakonenko Dr. Svitlana V. Shishkina Dr. Sergii S. Smola Dr. Nataliia V. Rusakova Dr. Tetiana Y. Sliva Dr. Paula Gawryszewska Dr. Albano N. Carneiro Neto Prof. Dr. Oscar L. Malta Prof. Dr. Vladimir M. Amirkhanov 《Chemphyschem》2022,23(14):e202200129
New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt4[LnL4] (Ln3+=La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt4+ on the structure and properties of the tetrakis-complex [LnL4]- is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of 5D0→7F4 transition, observed in the luminescence spectrum of NEt4[EuL4], is discussed based on theoretical calculations. 相似文献
74.
Calum Williams Yunuen Montelongo Jaime Oscar Tenorio‐Pearl Andrea Cabrero‐Vilatela Stephan Hofmann William I. Milne Timothy D. Wilkinson 《固体物理学:研究快报》2015,9(2):125-129
Digital holography requires arrays of small reconfigurable elements to achieve complex reconstruction of the hologram with common systems based on pixels utilizing liquid crystal on silicon (LCoS) technology. The backplane of a typical pixel element is potentially underutilized and thus relatively large physical areas exist in which information can be stored and exploited to give additional functionality to pixel elements. Polarisation and wavelength dependent optical properties can be achieved in small areas using the plasmonic effects of optical antennae. The integration of LCs with optical antennae‐based plasmonic holograms allows active modulation of the far field pattern. The work here demonstrates the concept that conventional LCoS pixel elements can be greatly enhanced with the integration of plasmonic holograms, composed of optical antennae patterned on the surface, giving rise to new levels of modulation capability for holographic pixel elements. Using LCs, polarisation dependent effects in plasmonic holograms can be switched. ‘Engineered pixels', with sub‐wavelength multiplexing over both polarisation and wavelength, can increase the channel capacity of a typical LC display device. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
75.
Rosa L. Camacho-Mendoza Eliazar Aquino-Torres Julian Cruz-Borbolla Jose G. Alvarado-Rodríguez Oscar Olvera-Neria Jayanthi Narayanan Thangarasu Pandiyan 《Structural chemistry》2014,25(1):115-126
DFT studies of both the Fe4 cluster and the Fe(110) surface interaction with pyrrole, furan, thiophene, and selenophene showed that selenophene forms a stabler adsorbate iron complex than the other heterocyclic molecules; this is consistent with the binding energy data that were calculated between the Fe cluster and the Fe(110) surface with the heterocycles. Furthermore, when the adsorption of the compounds with the iron cluster was analyzed by molecular orbital studies, the orbitals of selenophene overlapped more strongly with the Fe atom than that of the other molecules. In TD-DFT, the π → π* peak observed for the molecules disappeared when they formed complexes, and there appeared a charge transfer band (ligand to metal), thus confirming the coordination of these molecules with the cluster. The data suggest that the chemisorption is an exothermic process. 相似文献
76.
Oscar Hernandez Peter Pulay Philippe Maître Béla Paizs 《Journal of the American Society for Mass Spectrometry》2014,25(9):1511-1514
Using quantum chemical calculations and infrared multiphoton dissociation (IRMPD) spectroscopy in the fingerprint and X-H stretching regions, we demonstrate here that the all-Ala b 6 fragment ion features a macrocyclic structure with C2 symmetry. For this structure, the ionizing proton is equally shared by the Ala(1) and Ala(4) amide oxygens in a Zundel-type symmetric (X…H+…X) H-bond. Figure
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77.
78.
Platinum Complexes Containing Pyramidalized Germanium and Tin Dihalide Ligands Bound through σ,σ ME Multiple Bonds 下载免费PDF全文
Florian Hupp Dr. Mengtao Ma Franziska Kroll Dr. J. Oscar C. Jimenez‐Halla Dr. Rian D. Dewhurst Dr. Krzysztof Radacki Dr. Andreas Stasch Prof. Dr. Cameron Jones Prof. Dr. Holger Braunschweig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):16888-16898
We present the isolation of the first mononuclear dihalogermylene, and mono‐ and dinuclear stannylene complexes of transition metals. These exhibit exceptionally pyramidalized Group 14 centers. Additionally, removal of the halide substituents from the Ge/Sn atom was successfully performed in two ways, halide abstraction and reduction, leading to a variety of unusual structural motifs. 相似文献
79.
Boryl‐Functionalized σ‐Alkynyl and Vinylidene Rhodium Complexes: Synthesis and Electronic Properties 下载免费PDF全文
Prof. Dr. Holger Braunschweig Christopher K. L. Brown Dr. Rian D. Dewhurst Dr. J. Oscar C. Jimenez‐Halla Thomas Kramer Dr. Ivo Krummenacher Dr. Bernd Pfaffinger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(5):1427-1433
The synthesis, reactivity, and properties of boryl‐functionalized σ‐alkynyl and vinylidene rhodium complexes such as trans‐[RhCl(?C?CHBMes2)(PiPr3)2] and trans‐[Rh(C?CBMes2)(IMe)(PiPr3)2] are reported. An equilibrium was found to exist between rhodium vinylidene complexes and the corresponding hydrido σ‐alkynyl complexes in solution. The complex trans‐[Rh(C?CBMes2)(IMe)(PiPr3)2] (IMe=1,3‐dimethylimidazol‐2‐ylidene) was found to exhibit solvatochromism and can be quasireversibly oxidized and reduced electrochemically. Density functional calculations were performed to determine the reaction mechanism and to help rationalize the photophysical properties of trans‐[Rh(C?CBMes2)(IMe)(PiPr3)2]. 相似文献
80.
Jairo Amortegui Alexander Rodríguez-López Deicy Rodríguez Ana K. Carrascal Carlos J. Alméciga-Díaz Adelina del P. Melendez Oscar F. Sánchez 《Applied biochemistry and biotechnology》2014,172(7):3374-3389
Bacteriocins are low molecular peptides with antimicrobial activity, which are of great interest as food bio-preservatives and for treating diseases caused by pathogenic bacteria. In this study, we present the characterization of bacteriocins produced by Lactobacillus plantarum LE5 and LE27 isolated from ensiled corn. Bacteriocins were purified through ammonium sulfate precipitation and double dialysis by using 12- and 1-kDa membranes. Bacteriocins showed activity against Listeria innocua, Listeria monocytogenes, and Enteroccocus faecalis. Molecular weight was estimated through Tricine-SDS-PAGE and overloading the gel onto Mueller-Hinton agar seeded with L. monocytogenes, showing an inhibition zone between 5 and 10 kDa. NanoLC-MS/MS analysis allowed the identification of UPF0291 protein (UniProtKB/Swiss-Prot Q88VI7), which is also presented in other lactic acid bacteria without assigned function. Ab initio modeling showed it has an α-helix-rich structure and a large positive-charged region. Bacteriocins were stable between 4 and 121 °C and pH 2 and 12, and the activity was inhibited by SDS and proteases. Mode of action assay suggests that the bacteriocin causes of target microorganism. Taken together, these results describe a possible new class IIa bacteriocin produced by L. plantarum, which has a wide stability to physicochemical conditions, and that could be used as an alternative for the control of foodborne diseases. 相似文献