Article
Materials Science, Ceramics
Sushmita Dwivedi, Manish Badole, Hari Narayanan Vasavan, Sunil Kumar
Summary: The electrical conduction behavior of lead-free BiZnNbO ceramics annealed in different atmospheres was studied, with the sample annealed in oxygen environment showing the lowest conductivity due to reduced oxygen vacancy defects. An anomaly observed at 250 degrees Celsius in dielectric plots for certain samples was attributed to defect relaxation.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Mohamed A. Kolmangadi, Arda Yildirim, Kathrin Sentker, Martin Butschies, Andrea Buehlmeyer, Patrick Huber, Sabine Laschat, Andreas Schoenhals
Summary: The molecular mobility and conductivity of four bent shaped tetramethylated guanidinium based ionic liquid crystals with varying head group configuration and alkyl chain length were investigated using BDS and SHS techniques. Different relaxation processes and conductivity contributions were observed for the different ILCs, which may be related to their distinct molecular structures and formation mechanisms.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Materials Science, Ceramics
B. M. G. Melo, D. Blaskova-Kochnitcharova, S. Soreto Teixeira, E. Lefterova, P. Petkov, T. Petkova, L. C. Costa
Summary: Bulk samples of the ternary TiO2-V2O5-P2O5 system were synthesized using the melt-quenching technique. The structure and composition were identified using X-ray diffraction and scanning electron microscopy, with dielectric properties measured using impedance spectroscopy. Analysis of impedance spectra indicated a grain conductivity of 10-1 S/m at 190 degrees Celsius for the NASICON sample.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Rafael B. Nuernberg, Norma Maria P. Machado, Dylan Jouglard, Leire del Campo, Mohammed Malki, Muriel Neyret
Summary: The present work aims to unveil the nature of hysteresis response in the electrical conductivity of RuO2-glass composites melts. Experimental results show that the RuO2 content significantly affects the type of electrical conductivity, with hysteresis behavior mainly observed in regions where ionic conductivity is dominant.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Thermodynamics
Hazhir Fatahi, Jerome Claverie, Sebastien Poncet
Summary: This study investigates the rheological behavior of an organic phase change material, adipic acid, and compares the heat flow with rheological test results to provide detailed information on the phase transition range.
THERMOCHIMICA ACTA
(2022)
Article
Materials Science, Multidisciplinary
Rafael B. Nuernberg, Norma Maria P. Machado, Mohammed Malki, Muriel Neyret
Summary: This study aims to evaluate the influence of RuO2 particle size on the electrical behavior and percolation threshold of RuO2-glass composites. Experimental results show a transition in the electrical behavior of the composites near the percolation threshold, with low RuO2 content exhibiting ionic conductivity and high RuO2 content showing electronic conductivity. Additionally, the electrical properties of the composites are significantly affected by the size of RuO2 particles.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Vaidyanath Ramakrishnan, Johannes G. P. Goossens, Theodorus L. Hoeks, Gerrit W. M. Peters
Summary: This paper investigates the terminal viscosity behavior of a polymer melt containing grafted nanosilica particles, revealing that the viscosity of nanocomposites is influenced by the interaction between the polymer matrix and the nanoparticle surface. The study explores the trends in viscosity at different concentrations and suggests that the thickness of the graft layer plays a role in viscosity reduction.
Article
Materials Science, Ceramics
Vitoria Mussi Toschi, Christine Bogicevic, Houssny Bouyanfif, Henri Laville, Pierre-Eymeric Janolin
Summary: The study shows that nominal stoichiometry, phase separation, and metallization method significantly impact the dielectric properties of NBT-6BT material. Increasing the Na/Bi ratio leads to higher conductivity, dielectric losses, depolarization temperature, and lower temperature of maximum permittivity. Phase separation during synthesis results in secondary Ba-containing phases that can positively affect dielectric properties. The method of metallization also influences the dielectric properties, contributing to discrepancies in reported results.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Physics, Multidisciplinary
Yousaf Iqbal, Waqar Hussain Shah, Bisma Khan, Muhammad Javed, Hayat Ullah, Nadia Khan, Abdul Rauf Khan, Ghulam Asghar, Akif Safeen
Summary: In this study, the frequency and temperature dependent dielectric relaxation and electrical conduction mechanisms in NiAl2O4 spinel oxide ceramic were investigated. The results showed that the electrical conductivity of the material is governed by the thermally activated small polaron hopping mechanism.
Article
Polymer Science
Tiziana Bardelli, Claudia Marano, Francesco Briatico Vangosa
Summary: This study systematically investigated the crosslinking kinetics of Sylgard184 polydimethylsiloxane under isothermal and dynamic conditions. The results showed that rheological analysis was more sensitive over longer periods of time compared to thermal analysis. The gel point occurred at alpha(R) = 0.53, while alpha(C) was around 0.30 at the gel point, indicating that about 30% of the bonds involved in the crosslinking process were sufficient to create an infinite network. A modified version of Kamal's autocatalytic model was able to fit and predict the experimental findings.
JOURNAL OF APPLIED POLYMER SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Piotr Okoczuk, Natalia Anna Wojcik, Leon Murawski, Leszek Wicikowski, Marcin Stanislaw Lapinski, Piotr Winiarz, Barbara Koscielska
Summary: In this study, V2O5-TeO2 glass was prepared and its crystallization led to a significant increase in electrical conductivity and a decrease in activation energy. Existing charge transfer models, including Schnakenberg's and Friedman-Triberis', were found applicable to both glass and glass-ceramics. Structural studies revealed the main crystallizing phase to be Te2V2O9, which resulted in the reduction of vanadium ions and an increase in electrical conductivity.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Polymer Science
Polona Megusar, David Stopar, Natasa Poklar Ulrih, Iztok Dogsa, Iztok Prislan
Summary: Understanding the effects of hydroxypropyl methyl cellulose and xanthan gum on gluten-free dough can contribute to the development of better quality gluten-free bread with optimized ingredients.
Article
Multidisciplinary Sciences
W. A. Abu-raia, D. A. Aloraini, S. A. El-Khateeb, Aly Saeed
Summary: Research and development on new materials for optical filters is ongoing. This study prepared a bandpass filter using a glass doped with different concentrations of NiO. The glass showed amorphous essence in X-ray diffraction patterns and had high thermal stability. The Ni ions in the glass played a role as a network modifier, and the filter exhibited excellent electrical and optical performance.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Electrical & Electronic
M. Y. Li, C. He, W. G. Wang, G. L. Hao, X. Y. Li, T. Liu, X. F. Wang, D. Wang
Summary: The electrical properties of Ga3+ doping Na0.5Bi0.5TiO3-based oxygen ionic conductors were investigated, showing that the bulk conductivity decreased with higher Ga3+ doping concentration, but slight Ga3+ doping supported the enhancement of total conductivity. A relaxation peak was observed in the Na0.52Bi0.47Ti1-xGaxO3-delta compounds.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Polymer Science
Xuan Xue, Tianming Xiao, Yu Liu, Qichao Ran
Summary: In this study, an ordinary diamine-type benzoxazine resin (PH-ddm) was chosen as the research object to investigate its curing kinetics and rheological behavior using differential scanning calorimetry and rheological testing methods. A novel approach of using a TTT diagram to study the curing process of benzoxazine resins was proposed for the first time, providing an effective method for optimizing the molding conditions of benzoxazine resins.
JOURNAL OF APPLIED POLYMER SCIENCE
(2021)
Review
Chemistry, Multidisciplinary
Seungtaik Hwang, Juergen Haase, Erich Miersemann, Joerg Kaerger
Summary: The mass transfer in hierarchically porous materials is influenced by diffusivities in pore spaces, their populations, and exchange rates. The two-region model of diffusion, commonly known as the Karger equations, quantifies this interplay. Microscopic techniques, such as microimaging and NMR, provide experimental insight into dominant mechanisms of mass transfer, crucial for developing optimal performance enhancement strategies for such materials.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Chemistry, Physical
Christian Chmelik, Roger Glaeser, Juergen Haase, Seungtaik Hwang, Joerg Kaerger
Summary: Microimaging techniques based on interference microscopy and IR microscopy allow observation of guest molecule distribution in nanoporous solids and their changes over time. Understanding concentration gradients and diffusion fluxes provides direct insight into diffusion phenomena, including transport diffusion under non-equilibrium conditions and self- or tracer diffusion. Analysis of guest concentration near external surface compared to equilibrium value can also determine surface resistances.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2021)
Article
Chemistry, Physical
Joerg Kaerger, Marija Avramovska, Dieter Freude, Juergen Haase, Seungtaik Hwang, Rustem Valiullin
Summary: Labeling in diffusion measurements by PFG NMR is based on observing the phase of nuclear spins, providing information about molecular displacement probability distribution and its impact on chemical conversion in porous catalysts. The technique also showcases various concentration dependence patterns and transport inhibition by additional resistances within nanoporous particles.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2021)
Review
Chemistry, Multidisciplinary
Benworth B. Hansen, Stephanie Spittle, Brian Chen, Derrick Poe, Yong Zhang, Jeffrey M. Klein, Alexandre Horton, Laxmi Adhikari, Tamar Zelovich, Brian W. Doherty, Burcu Gurkan, Edward J. Maginn, Arthur Ragauskas, Mark Dadmun, Thomas A. Zawodzinski, Gary A. Baker, Mark E. Tuckerman, Robert F. Savinell, Joshua R. Sangoro
Summary: Deep eutectic solvents (DESs) exhibit significant depressions in melting points and tunable physicochemical properties, but there is still a lack of predictive understanding of their microscopic mechanisms and structure-property relationships. Research on complex hydrogen bonding is crucial for a deeper understanding and development of fundamental frameworks for DESs.
Article
Chemistry, Physical
Emmanuel Urandu Mapesa, Nobahar Shahidi, Friedrich Kremer, Manolis Doxastakis, Joshua Sangoro
Summary: Experimental and simulation results demonstrate that molecular dynamics in ultrathin layers are influenced by interfacial regions with thicknesses very close to the glass transition temperature, which are relevant for applications of polymers in adhesion, coatings, and polymer nanocomposites.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Polymer Science
Thomas Kinsey, Emmanuel Urandu Mapesa, Weiyu Wang, Kunlun Hong, Jimmy Mays, S. Michael Kilbey, Joshua Sangoro
Summary: The study investigated the impact of architectural asymmetry on the dielectric polymer relaxations in miktoarm star copolymers using broad-band dielectric spectroscopy and small-angle X-ray scattering. It was found that architecturally asymmetric systems exhibited distributions in relaxation times and strengths that were not dependent on molecular weight or morphology, contrasting with the effects observed in symmetric diblock systems. The results suggest that molecular architecture in block copolymers can serve as a versatile tool to control polymer chain dynamics and macroscopic properties.
Article
Materials Science, Ceramics
Marija Avramovska, Christian Chmelik, Arkadiusz Derkowski, Alexander Fantalkin, Dieter Freude, Juergen Haase, Vincent Hare, Joerg Kaerger, Artur Kuligiewicz, Murray Moinester
Summary: Determining the absolute ages of archaeological ceramics is crucial for understanding past societies and reconstructing accurate chronologies. Research using IR and NMR spectroscopy methods on clay materials can provide important insights into the elementary processes of mass transfer and hydroxylation, potentially refining the RHX dating method.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Polymer Science
Emmanuel Urandu Mapesa, Nelly M. Cantillo, Sara T. Hamilton, Matthew A. Harris, Thomas A. Zawodzinski, Ah-Hyung Alissa Park, Joshua Sangoro
Summary: Broadband dielectric spectroscopy, rheology, and nuclear magnetic resonance spectroscopy were used to study molecular dynamics in a nanoparticle organic hybrid material (NOHMs) system with 20 wt % silica nanoparticles ionically bonded to a polyethylenimine canopy. The timescales characterizing segmental dynamics in the NOHM were found to be the same as those for the neat polymer canopy. Detailed analysis of carbon-spin lattice relaxation times provided mechanistic insights into localized and collective dynamics, in agreement with dielectric results. The NOHMs exhibited liquid-like characteristics but had higher viscosity due to contributions from tethered polymer chains and mesoscopic structuring.
Article
Multidisciplinary Sciences
Matthew A. Harris, Thomas Kinsey, Durgesh Wagle, Gary A. Baker, Joshua Sangoro
Summary: A liquid-liquid transition (LLT) is a transformation from one liquid to another through a first-order transition, fundamental to understanding the liquid state. While LLT has been reported in some materials, experimental evidence for its existence in many molecular liquids remains controversial. Studying the local order and structural dynamics across an LLT provides unprecedented possibilities for understanding the nature of the liquid state.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Stephanie Spittle, Derrick Poe, Brian Doherty, Charles Kolodziej, Luke Heroux, Md Ashraful Haque, Henry Squire, Tyler Cosby, Yong Zhang, Carla Fraenza, Sahana Bhattacharyya, Madhusudan Tyagi, Jing Peng, Ramez A. Elgammal, Thomas Zawodzinski, Mark Tuckerman, Steve Greenbaum, Burcu Gurkan, Mark Dadmun, Edward J. Maginn, Joshua Sangoro
Summary: This article investigates the relationship between micro and macroscopic properties in deep eutectic solvents (DESs) Glyceline and Ethaline using computational and experimental techniques. The authors find that systematic addition of choline chloride leads to microscopic heterogeneities that alter structural relaxation and result in new dynamic modes strongly correlated to the macroscopic properties of the DESs formed.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Seungtaik Hwang, Daniel Schneider, Jurgen Haase, Erich Miersemann, Jorg Karger
Summary: The use of hierarchically organized nanoporous materials effectively counteracts transport hindrance in micropores. This paper confirms the validity of the two-region approach of diffusion for mass transfer and catalytic conversion through comparison with kinetic Monte Carlo simulations.
Article
Nanoscience & Nanotechnology
Colin M. Basham, Stephen A. Sarles, Joshua Sangoro, Joyce El-Beyrouthy, Eric Freeman, Stephanie Spittle
Summary: Understanding the physical effects of nanoparticles on plasma membranes is crucial for their design and clinical applications. In this study, functionalized gold nanoparticles dissolved in oil were directly trapped within a phospholipid membrane using the droplet interface bilayer technique. The trapped nanoparticles were found to enhance ion conductance and lateral membrane tension of the bilayers, while also reducing the adhesive energy of the droplets. This study provides insight into the interactions between nanoparticles and lipid membranes.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Polymer Science
Jonathan P. Coote, Samuel K. J. Adotey, Joshua R. Sangoro, Gila E. Stein
Summary: The ionic conductivity in lamellar block copolymer electrolytes is often anisotropic, with higher conductivity in the plane than through the plane. Previous work suggested that layering of lamellar domains near the electrode surface depressed the through-film ionic conductivity. However, this present study found that anisotropy in the ionic conductivity arises from an in-plane enhancement instead of a through-plane depression.
Article
Chemistry, Multidisciplinary
Bichitra Borah, Gobin Raj Acharya, Diana Grajeda, Matthew S. Emerson, Matthew A. Harris, Am Milinda Abeykoon, Joshua Sangoro, Gary A. Baker, Andrew J. Nieuwkoop, Claudio J. Margulis
Summary: This article reports on the structural-dynamic pathway from liquid to glass in ionic liquids containing a specific cation. Experimental and computational evidence suggests that the transition from liquid to glass occurs in separate stages.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Physics, Fluids & Plasmas
Shinian Cheng, Zaneta Wojnarowska, Joshua Sangoro, Marian Paluch
Summary: This paper compares the thermodynamics, ionic dynamics, and mechanical properties of pendant and backbone polymerized ionic liquids (PILs). The results show that pendant PILs have lower energy barrier for ion hopping and stronger sensitivity to pressure. A free-volume based model is proposed to explain the ion dynamics of these PILs under high-pressure conditions.
