Radionuclide migration in aquatic environment is influenced by its sorption onto colloids/mineral oxides and the presence of organic complexing anions. With a view to understand the sorption of trivalent actinides by mineral oxides in presence of organic acid, in the present study, Eu(III), malonic acid (MA) and γ-alumina are considered as representatives of trivalent actinides, low molecular weight natural occurring organic acid and aluminol sites, respectively. The influence of MA on sorption of Eu(III) by γ-alumina was elucidated by batch sorption, spectroscopic techniques and surface complexation modeling, for the first time. Attenuated Total Reflection-Fourier Transform Infrared spectroscopic studies of MA sorbed on γ-alumina revealed the presence of two inner-sphere surface complexes. Batch sorption for binary (alumina-Eu(III)) and ternary (alumina-Eu(III)-MA) systems were investigated as a function of pH, Eu(III) concentration and sequential addition of Eu(III)/MA. The pH edge for Eu(III) sorption shifts to higher pH with increasing Eu(III) concentration. In ternary systems, Eu(III) sorption is significantly enhanced at pH < 4.5. Eu(III) speciation on γ-alumina is independent of addition sequence of Eu(III)/MA. Time resolved fluorescence spectroscopy of Eu(III) sorbed on γ-alumina exhibited two surface species, XOEu and (YO)Eu. The enhancement in I/I and lifetime for ternary systems, as compared to binary system, at low pH, indicates the participation of Eu-MA complexes in the formation of surface species in ternary systems. The diffuse layer model has been employed to successfully model the experimental sorption profiles of binary and ternary systems, using code FITEQL 4.0, by considering the surface species identified by spectroscopic techniques.
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http://dx.doi.org/10.1016/j.jes.2020.07.020 | DOI Listing |
J Colloid Interface Sci
January 2025
Institute of Physical and Theoretical Chemistry, University of Regensburg D-93053 Regensburg, Germany. Electronic address:
Hypothesis: Due to its huge polar headgroup, octaoxyethylene octyl ether carboxylic acid (CECHCOOH = Akypo LF2™) is supposed not to be able to change its curvature sufficiently to form bicontinuous microemulsions. Instead, upon adding an oil to the binary water - surfactant system, excess oil could be squeezed out or a biliquid foam could form.
Experiments: An auto-dilution setup was used to record small-angle X-ray scattering data along six dilution lines in the newly established phase diagram of the ternary system 2-ethylhexanol - CECHCOOH - water.
RSC Chem Biol
January 2025
School of Chemistry, The University of Sydney Sydney NSW 2006 Australia
Targeted protein degraders, in the form of proteolysis targeting chimaeras (PROTACs) and molecular glues, leverage the ubiquitin-proteasome system to catalytically degrade specific target proteins of interest. Because such molecules can be extremely potent, they have attracted considerable attention as a therapeutic modality in recent years. However, while targeted degraders have great potential, they are likely to face many of the same challenges as more traditional small molecules when it comes to their development as therapeutics.
View Article and Find Full Text PDFSurface active ionic liquids (SAILs), offer potential advantages for pharmaceutical applications. Given the low permeability of gabapentin, an antiepileptic drug, in the gastrointestinal tract as classified by the Biopharmaceutics Classification Systems (BCS), understanding the micellization behavior of SAILs is essential for developing effective drug delivery systems to improve gabapentin bioavailability. This study explores the micellization and thermophysical behavior of SAILs (2-hydroxyethyl)ammonium laurate [2-HEA][Lau], bis(2-hydroxyethyl)ammonium laurate [BHEA][Lau], and tris(2-hydroxyethyl)ammonium laurate [THEA][Lau] in the presence of aqueous gabapentin solution at varied temperatures through COSMO analysis, electrical conductivity and surface tension measurements.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Institute of Advanced Materials and Systems, Sookmyung Women's University, Seoul 04310, Republic of Korea.
Multivalued logic (MVL) systems, in which data are processed with more than two logic values, are considered a viable solution for achieving superior processing efficiency with higher data density and less complicated system complexity without further scaling challenges. Such MVL systems have been conceptually realized by using negative transconductance (NTC) devices whose channels consist of van der Waals (vdW) heterojunctions of low-dimensional semiconductors; however, their circuit operations have not been quite ideal for driving multiple stages in real circuit applications due to reasons such as a reduced output swing and poorly defined logic states. Herein, we demonstrate ternary inverter circuits with near rail-to-rail swing and three distinct logic states by employing vdW p-n heterojunctions of single-walled carbon nanotubes (SWCNT) and MoS where the SWCNT layer completely covers the MoS layer.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
January 2025
Peter Gruenberg Institut (PGI-7), Forschungszentrum Juelich GmbH, Juelich, Germany.
The thirst for more efficient computational paradigms has reignited interest in computation in memory (CIM), a burgeoning topic that pivots on the strengths of more versatile logic systems. Surging ahead in this innovative milieu, multi-valued logic systems have been identified as possessing the potential to amplify storage density and computation efficacy. Notably, ternary logic has attracted widespread research owing to its relatively lower computational and storage complexity, offering a promising alternative to the traditional binary logic computation.
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