bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and self-diffusivity of mixed-cation electrolytes between neutral and charged graphene sheets
Authors: Rezlerová Eliška , Moučka Filip , Předota Milan , Lísal Martin 
Published: March 2024

Graphene-based applications, such as supercapacitors or capacitive deionization, take place in an aqueous environment, and they benefit from molecular-level insights into the behavior of aqueous electrolyte solutions in single-digit graphene nanopores with a size comparable to a few molecular diameters. Under single-digit graphene nanoconfinement (smallest dimension &lt;2 nm), water and ions behave drastically different than in the bulk. Most aqueous electrolytes in the graphene-based applications as well as in nature contain a mix of electrolytes. We study several prototypical aqueous mixed alkali-chloride electrolytes containing an equimolar fraction of Li/Na, Li/K, or Na/K cations confined between neutral and positively or negatively charged parallel graphene sheets. The strong hydration shell of small Li+ vs a larger Na+ or large K+ with weaker or weak hydration shells affects the interplay between the ions’s propensity to hydrate or dehydrate under the graphene nanoconfinement and the strength of the ion–graphene interactions mediated by confinement-induced layered water. We perform molecular dynamics simulations of the confined mixed-cation electrolytes using the effectively polarizable force field for electrolyte–graphene systems and focused on a relation between the electrochemical adsorption and structural properties of the water molecules and ions and their diffusion behavior. The simulations show that the one-layer nanoslits have the biggest impact on the ions’ adsorption and the water and ions’ diffusion. The positively charged one-layer nanoslits only allow for Cl− adsorption and strengthen the intermolecular bonding, which along with the ultrathin confinement substantially reduces the water and Cl− diffusion. In contrast, the negatively charged one-layer nanoslits only allow for adsorption of weakly hydrated Na+ or K+ and substantially break up the non-covalent bond network, which leads to the enhancement of the water and Na+ or K+ diffusion up to or even above the bulk diffusion. In wider nanoslits, cations adsorb closer to the graphene surfaces than Cl−’s with preferential adsorption of a weakly hydrated cation over a strongly hydrated cation. The positive graphene charge has an intuitive effect on the adsorption of weakly hydrated Na+’s or K+’s and Cl−’s and a counterintuitive effect on the adsorption of strongly hydrated Li+’s. On the other hand, the negative surface charge has an intuitive effect on the adsorption of both types of cations and only mild intuitive or counterintuitive effects on the Cl− adsorption. The diffusion of water molecules and ions confined in the wider nanoslits is reduced with respect to the bulk diffusion, more for the positive graphene charge, which strengthened the intermolecular bonding, and less for the negative surface charge, which weakened the non-covalent bond network.
Design and performance of an ultrahigh vacuum spectroscopic-imaging scanning tunneling microscope with a hybrid vibration isolation system
Authors: Chung Pei-Fang , Venkatesan Balaji , Su Chih-Chuan , Chang Jen-Te , Cheng Hsu-Kai , Liu Che-An , Yu Henry , Chang Chia-Seng , Guan Syu-You , Chuang Tien-Ming 
Published: March 2024

A spectroscopic imaging-scanning tunneling microscope (SI-STM) allows for the atomic scale visualization of the surface electronic and magnetic structure of novel quantum materials with a high energy resolution. To achieve the optimal performance, a low vibration facility is required. Here, we describe the design and performance of an ultrahigh vacuum STM system supported by a hybrid vibration isolation system that consists of a pneumatic passive and a piezoelectric active vibration isolation stage. We present the detailed vibrational noise analysis of the hybrid vibration isolation system, which shows that the vibration level can be suppressed below 10−8 m/sec/√Hz for most frequencies up to 100 Hz. Combined with a rigid STM design, vibrational noise can be successfully removed from the tunneling current. We demonstrate the performance of our STM system by taking high resolution spectroscopic maps and topographic images on several quantum materials. Our results establish a new strategy to achieve an effective vibration isolation system for high-resolution STM and other scanning probe microscopies to investigate the nanoscale quantum phenomena.
Four-wave mixing based spectral Talbot amplifier for programmable purification of optical frequency combs
Authors: Li Zijian , Xie Qijie , Zhang Yuanfei , Zhang Honghui , Huang Chaoran , Shu Chester 
Published: March 2024

Optical frequency combs (OFCs) with programmable free spectral range and high optical carrier-to-noise ratio (CNR) play a crucial role in diverse research fields, including telecommunications, spectroscopy, quantum information, astronomy, sensing, and imaging. Unfortunately, the presence of stochastic noise often results in degraded optical CNR, leading to limited communication performance and measurement accuracy in comb-based systems. There is a lack of effective and flexible methods to improve the CNR of OFCs contaminated by broadband noise, hampering their widespread utilization. To address this challenge, we propose a four-wave mixing based spectral Talbot amplifier to purify OFCs flexibly. Our approach employs programmable spectral phase filters followed by a nonlinear Kerr medium to regenerate an OFC with superior CNR. In our experimental demonstration, we regenerated a 165-GHz spaced CNR enhanced OFC from a noise-dominated comb source spaced at 11 GHz, achieving up to ∼11-dB CNR improvement. The technique allows for a user-defined purification factor m to range from 7 to 15. Furthermore, our scheme demonstrates flexibility in adjusting the wavelengths of the regenerated comb lines via a tunable optical delay line without the need for a tunable seed laser. We also investigated the impact of the pump and signal on the regenerated comb experimentally and studied the influence of dispersion mismatch on the suppression of undesired sidebands numerically. Our proposed scheme presents a powerful alternative for programmable purification, manipulation, and detection of noise-dominated spectral waveforms.
Vapor–liquid equilibrium and thermodynamic properties of saturated argon and krypton from Monte Carlo simulations using ab initio potentials
Authors: Ströker Philipp , Meier Karsten 
Published: March 2024

Vapor–liquid equilibria and thermodynamic properties of saturated argon and krypton were calculated by semi-classical Monte Carlo simulations with the NpT + test particle method using ab initio potentials for the two-body and nonadditive three-body interactions. The NpT + test particle method was extended to the calculation of second-order thermodynamic properties, such as the isochoric and isobaric heat capacities or the speed of sound, of the saturated liquid and vapor by using our recently developed approach for the systematic calculation of arbitrary thermodynamic properties in the isothermal–isobaric ensemble. Generally, the results for all simulated properties agree well with experimental data and the current reference equations of state for argon and krypton. In particular, the results for the vapor pressure and for the density and speed of sound of the saturated liquid and vapor agree with the most accurate experimental data for both noble gases almost within the uncertainty of these data, a level of agreement unprecedented for many-particle simulations. This study demonstrates that the vapor–liquid equilibrium and thermodynamic properties at saturation of a pure fluid can be predicted by Monte Carlo simulations with high accuracy when the intermolecular interactions are described by state-of-the-art ab initio pair and nonadditive three-body potentials and quantum effects are accounted for.
Changes of soil carbon along a topo-climatic gradient in rangelands of Iran: insights from 14C mean residence time and δ13C
Authors: Owji Alireza , Landi Ahmad , Hojati Saeed , Khodadadi Maral 
Published: March 2024

Context Soils can be the largest terrestrial carbon source and a potential sink of atmospheric CO2. Soil organic carbon (SOC) dynamics can be unravelled by 14C-derived mean residence times (MRT). Aims We aimed to understand SOC dynamics in surface and subsurface soils along a topo-climatic gradient in the rangelands of Khuzestan Province, Iran. Methods Study sites were selected under two contrasting regional climates in Izeh (MAT + 19.2°C, MAP 623 mm) and Ramhormoz (MAT + 27.5°C, MAP 200 mm). Soil physicochemical properties, SOC forms, and 14C MRT and δ13C signatures were determined in the control profiles. Key results The average MRT up to 1 m depth in Izeh and Ramhormoz were 2980 and 6582 years before present, respectively. On average, a loss of 300 Mg C ha−1 in SOC stocks and a rise of 430 years in SOC MRT up to 1 m can be expected per 1°C increase in MAT, 50 mm reduction in MAP, and 100 m decrease in elevation, highlighting the potential significance of MAT in SOC dynamics. Using optimistic and pessimistic carbon emission scenarios, carbon emissions in the upland areas were projected to be between 50 and 100 Mg C ha−1 over 80 years. Conclusions While the most influential element on SOC stock and its relative age was likely the temperature, other factors like erosion and deposition processes can cause enhanced SOC dislocation along the topo-climatic gradient. Implications Soil carbon pools stabilised for centuries to millennia are susceptible to alterations due to climate and land cover change.
Individual variation in contact effects – stability, convergence, and divergence
Authors: Barking Marie , Mos Maria , Backus Ad 
Published: March 2024

Abstract
In this study, we investigate the contact effects of stability, convergence, and divergence regarding the use of
the same linguistic construction in the same contact situation. To do that, we collected experimental production and judgment data
by native German speakers living in the Netherlands regarding their usage of the complementizer um ‘to’ in German
and compared those data to those of a control group of German speakers not in contact with Dutch. The results show that most
speakers show evidence for some contact-induced language change in their German. At the same time, speakers seem to experience
different contact effects, demonstrating that it is not the structural properties of the construction that result in one effect
over the other, but rather factors that pertain to the individual speakers. In particular, we argue that speakers can either focus
on the similarities or on the differences between their languages, to some extent driven by their attitudes towards their
languages and language change, and then over-generalize these similarities or differences to new contexts. Overall, this result
clearly underlines the importance of focusing on individual speakers as the initiators of language change, which is in line with a
usage-based approach.
Modelling gravitational-wave emission and detection on spandex using a high-speed camera
Authors: Molnár András , Czura Márk , Dercsényi Bence A 
Published: March 2024

Abstract
This paper demonstrates a variation of the rubber sheet experiment (Gravitational Waves Work Like This Drill on Spandex) for measuring the properties of modelled gravitational waves. Mechanically induced waves on the rubber sheet are observed by a high-speed camera and the slow-motion videos are analysed with the Tracker program. We describe the theoretical background and the execution of the measurement process. The measured displacements are suitable for modelling real gravitational-wave signals and determinating properties of the sources.
Cooperative properties of multiple quantum scattering: II. Coherentlasing
Authors: Enaki Nicolae A 
Published: March 2024

Abstract
The description model of the multiple scattering lasers using the superposition states between the generated photons in the ensemble of bi-modes of the resonator field, we introduced a concept of indistinguishable energy portions generated in the resonator following multiple scattering. Each of these quasi-quanta has energy equal to the difference between the pumping and scattering quantum energies at each step of multiple scattering. The conversion of the photons in the external electromagnetic mode of the resonator destroys this cooperative correlation between the bi-modes and established conservation lows during the cooperative emission. The master equation containing two parameters connected with the gain of quasi-energy portions, and their annihilation due to the losses from the resonator, is proposed. The competition between these two processes is numerically studied. An attractive problem is connected with established quantum correlations between the photons belonging to non-adjacent modes of the cavity. The time behavior of the evolution of correlations between such modes is observed. This conception may be used for the teleportation of information in other modes during the multiple Raman conversion.
A very thin MRPC developed for TOF-PET
Authors: Liu J. , Wang Y. , Guo B. , Han D. , Li Y. 
Published: March 2024

Abstract
PET (Positron Emission Tomography) is a medical molecular imaging modality employed in cancer diagnosis and monitoring. Multi-gap Resistive Plate Chambers (MRPCs) are utilized in Time of Flight (TOF)-PET due to their superior time resolution. Our research group has successfully developed a 4-chamber 32-gap MRPC prototype with 0.128 mm gap thickness. The measured time resolution for cosmic rays is 20 ps, while the time resolution for the time difference between 0.511 MeV photon pairs is 193 ps Full Width at Half Maximum (FWHM). The 23.6 mm thickness of the MRPC prototype will affect the time resolution. To investigate the influence of the number and total thickness of gas gaps on the time resolution, Geant4 software is used to simulate the interaction between particles (such as cosmic rays and photons) and MRPC detectors. Most of the gamma photons interact with the resistive plates in MRPCs. It is ejected mostly a Compton electron into one gas gap, causing the gas ionization. In this paper, two 8-gap MRPC prototypes with 0.128 mm gap thickness and 4.2 mm total thickness are fabricated and tested. The time resolution of 39 ps for cosmic rays and 166 ps FWHM for 0.511 MeV photons is obtained using the fast front-end amplifier and waveform acquisition system. So, a real time PET image can be obtained with a pair of MRPCs, and the detection efficiency for gamma can be improved by increasing the number of thin MRPCs.
Enhanced formic acid electro-oxidation reaction over Ir,N-doped TiO2-supported Pt nanocatalyst
Authors: Huynh Tai Thien , Huynh Quyen , Huynh Ngoc-Han T , Pham Hau Quoc 
Published: March 2024

Abstract
In this work, we prepared an Ir,N-doped TiO2 nanomaterial via a facile HNO3-assisted hydrothermal process that was used as an advanced support for nano-sized Pt nanoparticles (NPs) for the formic acid oxidation reaction (FAOR). The physical and electrochemical behaviours of the as-made Pt/Ir,N-doped TiO2 catalyst were systemically investigated through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), field emission scanning electron microscopes coupled with energy dispersive X-ray analysis (FE-SEM/EDX mapping), transmission electron microscopy (TEM), linear sweep voltammetry (LSV), Tafel slope, CO-stripping, and chronoamperometric (CA) test. The Pt NPs (ca. 3 nm) were anchored on the Ir,N-doped TiO2 support, being formed by a mixture of rutile and brookite with a particle size of several ten nanometers. Due to the small size and uniform distribution of Pt NPs, the Pt/Ir,N-doped TiO2 catalyst had an electrochemical surface area of 79.88 m2 g−1, which was greater than that of the commercial Pt/C (77.63 m2 g−1). In terms of the FAOR, the Pt/Ir,N-doped TiO2 catalyst showed a negative FAOR onset potential, high current density (11.85 mA cm−2), and superior CO-tolerance compared to the commercially available catalyst. Also, the as-made catalyst possessed high electrochemical durability after 3600 s for testing. The enhanced FAOR efficiency was assigned to the formation of a dual-doping effect and strong interplay between Pt and TiO2-based support, which not only improved the electron transfer but also weakened the adsorption of carbonaceous species, thereby boosting the reaction kinetics. This study could open up a facile but effective strategy to promote particular electrochemical applications.
Interactions between forsythoside E and two cholinesterases at the different conditions: fluorescence sections
Authors: Lin Conghuan , Du Huizhi 
Published: March 2024

Abstract
Forsythoside E is one secondary metabolite of Forsythia suspensa (Thunb.) Vahl. In the study, the interactions between forsythoside E and two types of cholinesterases, acetylcholinesterase and butyrylcholinesterase were investigated in the different conditions. Forsythoside E increased the fluorescence intensity of acetylcholinesterase but quenched the fluorescence of butyrylcholinesterase. Aβ
25-35 used in the study may not form complexes with cholinesterases, and did not affect the interaction between forsythoside E and cholinesterases. The charged quaternary group of AsCh interacted with the ‘anionic’ subsite in acetylcholinesterase, which did not affect the interaction between forsythoside E and acetylcholinesterase. The enhancement rate of forsythoside E to acetylcholinesterase fluorescence from high to low was acid solution (pH 6.4), neutral solution (pH 7.4) and alkaline solution (pH 8.0), while the reduction rate of forsythoside E to butyrylcholinesterase fluorescence was in reverse order. Metal ions may interact with cholinesterases, and increased the effects of forsythoside E to cholinesterases fluorescence, in order that Fe3+ was the highest, followed by Cu2+, and Mg2+. A forsythoside E-butyrylcholinesterase complex at stoichiometric ratio of 1:1 was spontaneously formed, and the static quenching was the main quenching mode in the process of forsythoside E binding with butyrylcholinesterase. The K values of two complexes were pretty much the same, suggesting that the interaction between cholinesterases and forsythoside E was almost unaffected by acid–base environment and metal ions. The n numbers of two cholinesterases approximately equaled to one, indicating that there was only one site on each cholinesterase applicable for forsythoside E to bind to.
Will the US Survive the Frog? Time and History in the Pandemic and Decline
Authors: Haines Christian P 
Published: March 2024

Abstract
This essay examines two books, Jed Esty’s The Future of Decline: Anglo-American Culture at its Limits (2022) and an edited collection, The Long 2020 (2022), in terms of their respective geometries of history, or the ways in which they extrapolate possible futures for the US from contemporary material conditions. It considers the decline of US global hegemony and the crisis of the COVID-19 pandemic insofar as they puncture the nationalist fantasies of US exceptionalism. It also makes a case for steering between the alternatives of apocalypse and redemption in favor of a historical materialist reckoning with US socioeconomic decline. Learning from crisis and decline, the essay argues, doesn’t have to mean surrendering radical political or utopian impulses. It can also mean recasting social hope as the collective reclaiming of freedom from exceptionalism. Finally, the essay makes a methodological proposal for bringing together existential and structural approaches to history (or new materialist and Marxist modes of analysis) in literary and cultural studies, as well as critical theory.
Divergence and reticulation in the Mexican white oaks: ecological and phylogenomic evidence on species limits and phylogenetic networks in the Quercus laeta complex (Fagaceae)
Authors: Morales-Saldaña Saddan , Hipp Andrew L , Valencia-Ávalos Susana , Hahn Marlene , González-Elizondo M Socorro , Gernandt David S , Pham Kasey K , Oyama Ken , González-Rodríguez Antonio 
Published: March 2024

Abstract

Background and Aims
Introgressive hybridization poses a challenge to taxonomic and phylogenetic understanding of taxa, particularly when there are high numbers of co-occurring, intercrossable species. The genus Quercus exemplifies this situation. Oaks are highly diverse in sympatry and cross freely, creating syngameons of interfertile species. Although a well-resolved, dated phylogeny is available for the American oak clade, evolutionary relationships within many of the more recently derived clades remain to be defined, particularly for the young and exceptionally diverse Mexican white oak clade. Here, we adopted an approach bridging micro- and macroevolutionary scales to resolve evolutionary relationships in a rapidly diversifying clade endemic to Mexico.

Methods
Ecological data and sequences of 155 low-copy nuclear genes were used to identify distinct lineages within the Quercus laeta complex. Concatenated and coalescent approaches were used to assess the phylogenetic placement of these lineages relative to the Mexican white oak clade. Phylogenetic network methods were applied to evaluate the timing and genomic significance of recent or historical introgression among lineages.

Key Results
The Q. laeta complex comprises six well-supported lineages, each restricted geographically and with mostly divergent climatic niches. Species trees corroborated that the different lineages are more closely related to other species of Mexican white oaks than to each other, suggesting that this complex is polyphyletic. Phylogenetic networks estimated events of ancient introgression that involved the ancestors of three present-day Q. laeta lineages.

Conclusions
The Q. laeta complex is a morphologically and ecologically related group of species rather than a clade. Currently, oak phylogenetics is at a turning point, at which it is necessary to integrate phylogenetics and ecology in broad regional samples to figure out species boundaries. Our study illuminates one of the more complicated of the Mexican white oak groups and lays groundwork for further taxonomic study.
Multifunctional enzymes related to amino acid metabolism in bacteria
Authors: Miyamoto Tetsuya 
Published: March 2024

Abstract
In bacteria, d-amino acids are primarily synthesized from l-amino acids by amino acid racemases, but some bacteria use d-amino acid aminotransferases to synthesize d-amino acids. d-Amino acids are peptidoglycan components in the cell wall involved in several physiological processes, such as bacterial growth, biofilm dispersal, and peptidoglycan metabolism. Therefore, their metabolism and physiological roles have attracted increasing attention. Recently, we identified novel bacterial d-amino acid metabolic pathways, which involve amino acid racemases, with broad substrate specificity, as well as multifunctional enzymes with d-amino acid-metabolizing activity. Here, I review these multifunctional enzymes and their related d- and l-amino acid metabolic pathways in Escherichia coli and the hyperthermophile Thermotoga maritima.