Search Results - "Vaca Chávez, Fabián"

Time-Domain NMR Observation of Entangled Polymer Dynamics: Universal Behavior of Flexible Homopolymers and Applicability of the Tube Model by Vaca Chávez, Fabián, Saalwächter, Kay

“…Using a benchtop NMR spectrometer, we performed proton multiple-quantum NMR experiments to study the dynamics of well-entangled linear poly(butadiene),…”
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Diffusion of Water and Electrolytes in Mesoporous Silica with a Wide Range of Pore Sizes by Martínez Casillas, Diana C, Longinotti, M. Paula, Bruno, Mariano M, Vaca Chávez, Fabián, Acosta, Rodolfo H, Corti, Horacio R

“…The diffusion of alkaline chlorides (LiCl, KCl, and CsCl) and water in mesoporous silica samples with pore sizes covering the range from micropores (2 nm) up…”
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Speciation and Proton Conductivity of Phosphoric Acid Confined in Mesoporous Silica by Trevani, Liliana N., Lépori, Cristian M. O., Garro Linck, Yamila, Monti, Gustavo A., Abuin, Graciela C., Vaca Chávez, Fabián, Corti, Horacio R.

“…Phosphoric acid (PA) confined in a commercial mesoporous silica (CARIACT G) with porous size in the range of 3 to 10 nm was studied in relation to its…”
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Time-Domain NMR Observation of Entangled Polymer Dynamics: Analytical Theory of Signal Functions by VACA CHAVEZ, Fabian, SAALWÄCHTER, Kay

“…We present a full analytical treatment of signal functions in time-domain NMR of entangled polymer melts. Our approach is based on the segmental orientation…”
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CO2 in 1-Butyl-3-methylimidazolium Acetate. 2. NMR Investigation of Chemical Reactions by Besnard, Marcel, Cabaço, M. Isabel, Vaca Chávez, Fabián, Pinaud, Noël, Sebastião, Pedro J, Coutinho, João A. P, Mascetti, Joëlle, Danten, Yann

“…The solvation of CO2 in 1-butyl-3-methylimidazolium acetate (Bmim Ac) has been investigated by 1H, 13C, and 15N NMR spectroscopy at low CO2 molar fraction (mf)…”
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Confinement Effects on Chain Dynamics and Local Chain Order in Entangled Polymer Melts by Ok, Salim, Steinhart, Martin, Şerbescu, Anca, Franz, Cornelius, Vaca Chávez, Fabián, Saalwächter, Kay

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Characterization of structure and functionality of porous materials by Velasco, Manuel I., Franzoni, María Belén, Chávez, Fabián Vaca, Acosta, Rodolfo H.

“…•Diffusion and relaxation single-sided NMR.•Lithium confined in mesoporous carbons.•Modeling of energy adsorption energies. Nuclear magnetic resonance is…”
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Dynamics of binary mixtures of an ionic liquid and ethanol by NMR by Ordikhani Seyedlar, Amin, Martins, João Pedro de Almeida, Sebastião, Pedro J., Jardim Beira, Maria José, Stapf, Siegfried, Vaca Chávez, Fabián, Mattea, Carlos

“…A study of molecular dynamics of the ionic liquid 1‐ethyl‐3‐methylimidazolium bis(trifluoro‐methylsulphonyl)imide ([Emim][Tf2N]) in solution with deuterated…”
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Charge Templates in Aromatic Plus Ionic Liquid Systems Revisited: NMR Experiments and Molecular Dynamics Simulations by Dias, Nuno, Shimizu, Karina, Morgado, Pedro, Filipe, Eduardo J. M, Canongia Lopes, José N, Vaca Chávez, Fabián

“…The mutual solubilities of [C2C1im][Ntf2] ionic liquid and aromatic molecules (benzene and its fluorinated derivatives) can be correlated to the dipolar and…”
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Proton NMR relaxation study of molecular dynamics of chromonic liquid crystal Edicol Sunset Yellow by Cachitas, Hugo, Sebastião, Pedro J., Feio, Gabriel, Vaca Chávez, Fabián

“…Proton nuclear magnetic resonance ( 1 H NMR) relaxometry, over about five decades in Larmor frequency, and pulsed field gradient NMR were used to study the…”
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Dynamics of Discotic Fluoroalkylated Triphenylene Molecules Studied by Proton NMR Relaxometry by Vaca Chávez, Fabián, Sebastião, Pedro J, Miyake, Yasuo, Monobe, Hirosato, Shimizu, Yo

“…The Larmor frequency and temperature dependence of the proton nuclear magnetic resonance (NMR) spin–lattice relaxation time was measured in the isotropic and…”
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1H NMR Relaxometry, Viscometry, and PFG NMR Studies of Magnetic and Nonmagnetic Ionic Liquids by Daniel, Carla I, Vaca Chávez, Fabián, Feio, Gabriel, Portugal, Carla A. M, Crespo, João G, Sebastião, Pedro J

“…A study is presented of the molecular dynamics and of the viscosity in pure [Aliquat][Cl] ionic liquid and in a mixture of [Aliquat][Cl] with 1% (v/v) of…”
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Effect of acid treatment on the physico-chemical properties of Nafion 117 membrane by Iriarte, Delfina, Andrada, Heber, Maldonado Ochoa, Santiago A., Silva, O. Fernando, Vaca Chávez, Fabián, Carreras, Alejo

“…In this work, the effect on the physico-chemical properties of Nafion 117 membrane due to the treatment with HCl, H2SO4 and HNO3 was studied. Water uptake,…”
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NMR observation of entangled polymer dynamics: tube model predictions and constraint release by Vaca Chávez, Fabián, Saalwächter, Kay

“…We use a benchtop NMR technique to monitor entangled polymer melt dynamics over 5 decades in time covering regimes II-IV of the tube model. We confirm the…”
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Dynamics and spatial distribution of water in Nafion 117 membrane investigated by NMR spin-spin relaxation by Andrada, Heber E., Franzoni, María B., Carreras, Alejo C., Chávez, Fabián Vaca

“…The dynamics and spatial distribution of water molecules in Nafion 117 membrane has been investigated by 1H NMR. To this end, 1D and 2D spin-spin (T2)…”
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Hydrogen Exchange and Hydration Dynamics in Gelatin Gels by Vaca Chávez, Fabian, Hellstrand, Erik, Halle, Bertil

“…Gelatin, derived from the collagen triple helix, is the most widely used functional biopolymer and a prototype for studies of physical gels. Gelatin gels have…”
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Fe(III) salEen derived Schiff base complexes as potential contrast agents by Cardoso, Bernardo de P., Vicente, Ana I., Ward, Joseph B.J., Sebastião, Pedro J., Chávez, Fabián Vaca, Barroso, Sónia, Carvalho, Alexandra, Keely, Stephen J., Martinho, Paulo N., Calhorda, Maria José

“…Three new Fe(III) compounds of general formula [Fe(R-salEen)2]Cl (R=H, 1; 5-Br, 2; 3-OMe, 3) have been synthesised. The relaxivities for 2 are in agreement…”
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Molecular Dynamic Evaluation of starch-PLA blends nanocomposite with organoclay by proton NMR relaxometry by Brito, Luciana M., Chávez, Fabián Vaca, Bruno Tavares, Maria Inês, Sebastião, Pedro J.O.

“…Starch and PLA were used alone and in blends to prepare nanostructured materials using both hydrophilic and organophilic clays, and PVA. All nanostructured…”
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Internal Water Molecules and Magnetic Relaxation in Agarose Gels by Vaca Chávez, Fabian, Persson, Erik, Halle, Bertil

“…Agarose gels have long been known to produce exceptionally large enhancements of the water 1H and 2H magnetic relaxation rates. The molecular basis for this…”
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1H NMR relaxometry and X-ray study of PCL/nevirapine hybrids by Monteiro, Mariana S.S.B., Chávez, Fabián Vaca, Sebastião, Pedro. J., Tavares, Maria Inês Bruno

“…Polycaprolactone (PCL) hybrids containing layered silicates, silica and dioxide titanium were developed and used as matrixes for the incorporation of…”
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