Wide Region Research Articles

Fundamentals and Implication of Point of Zero Charge (PZC) Determination for Activated Carbons in Aqueous Electrolytes.

The point of zero charge (PZC) is a crucial parameter for investigating the charge storage mechanisms in energy storage systems at the molecular level. This paper presents findings from three different electrochemical techniques, compared for the first time: cyclic voltammetry (CV), staircase potentio electrochemical impedance spectroscopy (SPEIS), and step potential electrochemical spectroscopy (SPECS), for two activated carbons (ACs) with 0.1molL-1 aqueous solution of LiNO3, Li2SO4, and KI. The charging process of AC operating in aqueous electrolytes appears as a complex phenomenon - all ionic species take an active part in electric double-layer formation and the ion-mixing zone covers a wide potential region. Therefore, the so-called PZC should not be considered as an absolute one-point potential value, but rather as a range of zero charge (RZC). SPECS technique is found to be a universal and fast method for determining RZC, as applied here together with the EQCM. In most cases, the RZC covers a potential range from ≈100 to ≈200mV and the correlation of the range with the carbon microtexture is clear, highlighting the role of the ion-sieving effect. It is postulated that PZC for porous materials in aqueous electrolytic solutions should be considered instead as RZC.

Skyrmion soliton motion on periodic substrates by atomistic and particle based simulations

Abstract We compare the dynamical behavior of magnetic skyrmions interacting with square and triangular defect arrays just above commensuration using both atomistic and particle-based models. Under applied drives, the initial motion is a kink traveling through the pinned skyrmion lattice. For the square defect array, both models agree well and show a regime in which the soliton motion is locked along 45°. The atomistic model also produces locking of a soliton along 30°, which is absent in the particle-based model. For the triangular defect array, the atomistic model exhibits 30° soliton motion over a wide region of external current values. In contrast, the particle-based model gives 45° soliton motion over a small range of external driving force values. The difference arises because the nondeforming particle model facilitates meandering skyrmion orbits while the deformable atomistic model enables stronger skyrmion-skyrmion interactions that reduce the meandering. Our results indicate that soliton motion through pinned skyrmion lattices on a periodic substrate is a robust effect.

Effect of bone-borne maxillary skeletal expanders on cranial and circummaxillary sutures: A cone-beam computed tomography study.

Miniscrew-assisted maxillary expansion devices are frequently used for patients with calcified midpalatal sutures. This study aimed to evaluate the effects of two bone-borne maxillary expansion appliances on the cranial and circummaxillary sutures by comparing cone-beam computed tomography (CBCT) images before and after transverse maxillary expansion. A total of 81 patients (women = 58, men = 23) were treated with either a C-expander (n = 44) or an ATOZ expander (n = 37). CBCT images were obtained before (T0) and after (T1) maxillary expansion, and the widths of 10 circummaxillary sutures were measured in the sagittal, coronal, and axial planes. The Wilcoxon signed-rank test was used to compare the changes in suture width between the C-expander and ATOZ groups, and statistical significance was set at P < 0.05. The frontonasal, frontomaxillary, pterygomaxillary, nasomaxillary, internasal, intermaxillary, and midpalatal suture widths increased significantly after maxillary expansion in both the ATOZ and C-expander groups (both P < 0.05). The frontozygomatic, zygomaticomaxillary, and temporozygomatic suture widths decreased in the C-expander group (P < 0.05), whereas the frontozygomatic suture width increased significantly in the ATOZ group (P < 0.05). The width changes of the frontozygomatic, zygomaticomaxillary, temporozygomatic, pterygomaxillary, internasal, intermaxillary, and midpalatal sutures differed significantly between the two groups (P < 0.05). Both the C- and ATOZ expanders affected the suture width in the naso-maxillozygomatic region. The C-expander decreased the circum-zygomatic suture widths, whereas the ATOZ expander widened the frontozygomatic suture with no effect on other circummaxillary sutures.

Silver from the North

Following Strabo, the mines at Damastion and in its wider region have traditionally been localized in western Illyria. But for several reasons the only known ancient silver mine, west of the Axios, in the Openika hills up modern Ohrid, is no option. Findspots of coins of the Damastion type, minted after the Chalkidian model, however hint at the wider Skupi/Skopje basin as an area of circulation and as a center of silver commerce. Two ancient mining districts can be located not far off, to its east and north, in the regions of Kratovo (in modern North Macedonia) and (somewhat later) Ulpianum (in Kosovo or southern Serbia). From both districts, in the first half of the 4th c., mineral silver travelled south via the Axios Valley and the Anthemous region to the federal Chalkidian mint at Olynthos. The mines in the Kratovo district bordered on Hellenized Paionia, whereas those in the north, belonging to Dardania, were far less in touch with Greek civilization. Damastion’s location, probably in the Paionian borderlands, accounts for the Greek character of its coins. They became models for those from Dardanian mines which, however, soon fell off Greek standards. Nonetheless, Damastion kept close connections with the Chalkidians: soon after the Peloponnesian War it had been founded by the Mendaians and other groups including refugees from Aigina. Chalkidian economic connections with the Dardanian north, based on silver trade, were an impulse for a defensive alliance that the Illyro-Dardanian king Grabos concluded around 357 with the Chalkidians against Philip. Extremely short-lived, it was cancelled by the Olynthians when they accepted Philip’s offer of a symmachy. They threw the stele inscribed with their Dardanian alliance into a river flowing by their city even before it was fully incised.

Transpolar Arcs Are Not Always Cusp‐Aligned: Evidence of HiLDA‐Aligned Arcs

AbstractTranspolar arcs (TPAs) are often cusp‐aligned. Especially when multiple TPAs appear simultaneously, they join at the auroral signature of the cusp. Here we investigate the dayside connection point of TPAs using Defense Meteorological Satellite Program measurements and identify three cases where the tip of the TPA ends in a localized brightening. One is a typical cusp spot with a TPA attached. The cusp appears just poleward of the oval with a near circular shape. In the second case, multiple cusp spots are observed over a 3 MLT wide region, each connected to a TPA. In the third case, the brightening at the tip of a TPA is identified as high‐latitude dayside aurora (HiLDA). Cusp aurora appears between the HiLDA and the duskside oval. Plasma flows and particle characteristics indicate a lobe origin of the HiLDA. Our results indicate a more complicated connection between TPAs and dayside aurora than previously anticipated.

Flexural behavior of UHPC wet joints for precast bridge deck panels

Over the past decade or so, ultra-high performance concrete (UHPC) has been increasingly used for wet joints of bridge deck panels (BDPs) in bridge superstructures. To evaluate the flexural performance of UHPC wet joints for precast bridge deck panels, a total of seven BDPs were designed, including one monolithic cast-in-place bridge deck panel (MCIPBDP), one precast bridge deck panel (PBDP) with NC wet joints, and five precast bridge deck panels (PBDPs) with UHPC wet joints. The design parameters included reinforcement types (straight bars and U-bars), U-bar lap details (contact lap splice and non-contact lap splice), filling materials (UHPC and NC), and joint widths (150 mm, 200 mm, 250 mm, and 500 mm). Three-point bending tests were performed to evaluate the flexural performance based on the failure mode, load-deflection curve, cracking width in the wet joint region, and stiffness degradation. The experimental results showed that it is feasible to replace 500-mm-width NC wet joints with 200-mm-width UHPC wet joints for PBDPs with U-bars. UHPC wet joints, with a width of 250 mm, effectively prevented straight bars from slipping. As the width of UHPC wet joints decreased, the failure mode shifted from shear failure to bending failure. In addition, the cohesion-friction hybrid model was proposed to simulate the behavior of joint interfaces. The FE analysis results demonstrated that the FE model and modeling method have high accuracy and general applicability. Finally, the flexural capacity calculation formula was developed according to the strut-and-tie model. The theoretical calculation results were in good agreement with test results.

Nanoscale wettability characterization—Interpreting droplet morphological evolution in nanopores

AbstractNanoscale wettability, crucial for various disciplines in science and engineering, challenges traditional theory, particularly the Young's equation. This study proposes and validates a modified format of the Young's equation under nano‐confinement and, for the first time, the nano‐confined droplet morphological evolution and transition are investigated from thermodynamic theories and molecular dynamics simulation. The morphologies of droplets in nano‐silts, identified as double‐cap, single‐cap, and bridge‐shaped, underscore the critical roles of line tension and nano‐confinement in characterizing wetting behavior. In hydrophobic nano‐slits, droplets transition from the double‐cap to the single‐cap shape at the critical point of = 0.31 and to bridge shape at the critical point of = 0.40. Moreover, the relative width of the neck region in the bridge‐shaped droplets is found to stabilize at ratio of 1.8. Particularly, linear relationships have been established between the droplet contact angle and the parameter , which identify condensation and breakage of droplets within hydrophobic nano‐slits. This model effectively characterizes nanoscale wettability, with precise droplet behavior predictions, which could be beneficial to enhance nano‐fluid dynamics understanding and its applications in science and engineering.

Numerical determination of the threshold magnetic field in superconducting strips and coils triggering dynamic resistance

Abstract The threshold magnetic field is a key parameter for evaluating the current decay caused by dynamic resistance in superconducting windings and magnets. For a DC-carrying superconducting slab under an AC parallel magnetic field, the analytical theory clearly shows that there is only one electric central line (ECL) across the slab width at the onset of dynamic-resistance. However, threshold magnetic fields in superconducting strips and coils have not been fully investigated. Based onthe one-ECL criterion, this paper first presents a method for numerically determining the threshold magnetic field via the evolving internal magnetic field in superconducting strips and coils. By probing transient electromagnetic behaviours, interestingly, we found a distinctive feature of superconducting strips in which a wide region of zero electrical field is observed when dynamic resistance/loss initially occurs. With increasing magnetic fields, this region gradually shrinks and eventually become the ECL. More importantly, this numerical method can analyse the local threshold magnetic field in a targeted coil turn. The ability to quantify threshold magnetic field provides a clear guidance on the acceptable level of ripple and harmonic magnetic fields for coil windings in superconducting maglev trains and field windings of superconducting machines operating at persistent current mode.&amp;#xD;

Toscana virus - an emerging Mediterranean arbovirus transmitted by sand flies.

Toscana virus (TOSV) is an emerging arthropod-borne virus (arbovirus) of medical importance that is increasing its range across much of the Mediterranean Basin, Europe and the Middle East. Transmitted by Phlebotomus spp. sand flies, it is the most clinically relevant sand fly-borne phlebovirus. Initially isolated in the Tuscany region of Central Italy, it has now been detected in multiple countries that surround this geographical area. Infection of the vertebrate host can cause fever and neurological disease, following the dissemination of the virus to the brain. The prevalence is high in some regions, with a notable percentage of individuals showing seroconversion. TOSV can be a leading cause of acute meningitis and encephalitis (AME) during the summer months. In this comprehensive review, we will focus on several key topics. We discuss how TOSV has spread to establish outbreaks of infection in both humans and animals around the Mediterranean and the wider region. Clinical aspects of TOSV infection in humans are described, along with the best standards in diagnosis. Finally, we focus our discussion on the role of the sand fly vector, describing their biology, vector competency, implications for putative vertebrate reservoirs, the effect of the climate emergency on sand fly distribution and the putative role that sand fly-derived salivary factors may have on modulating host susceptibility to TOSV infection.

Molecular-level insight into the role of soil-derived dissolved organic matter composition in regulating photochemical reactivity

Soil-derived dissolved organic matter (DOM) links soil and water carbon pools and is an important source of photochemically produced reactive intermediates (PPRIs) in aquatic environments. Despite its importance, the variations in photochemical reactivity of soil-derived DOM molecules in producing PPRIs across broad geographical regions, and the factors driving these variations, remain unclear. Herein, we resolved the apparent quantum yields (Φ(PPRIs)) of hydroxyl radicals (•OH), singlet oxygen (1O2), and excited triplet-state DOM (3DOM*) for irradiated DOM from 22 representative soil reference materials in China, and linked them to soil pH, mineral weathering degree, and DOM characteristics. Generally, the average Φ(PPRIs) values of the soil-derived DOM followed the order of Φ(3DOM*) (1.67× 10−2) > Φ(1O2) (1.47× 10−2) > Φ(•OH) (7.31× 10−5). The DOM from less weathered soils showed higher Φ(•OH) and Φ(3DOM*) and comparable Φ(1O2) than that from more weathered soils. The differences were mainly regulated by the abundance of humic-, lignin-, tannin-, and aromatic-like compounds, as indicated by the correlation and random forest model analyses. Partial least squares and multiple linear regression analyses identified DOM molecular weight, nominal oxidation state of carbon, and soil chemical index of alteration as effective predictors of •OH yields. Soil chemical index of alteration emerged as a prioritized predictor of 3DOM* yields, while the electron-donating capacity and humic-like compound content of the soil-derived DOM were effective predictors of 1O2 yields. This study advances our understanding of how mineral weathering processes regulate the photochemical reactivity of soil-derived DOM in the aquatic environment across wide geographical regions.

TeO[formula omitted]–BaO–Bi[formula omitted]O[formula omitted] tellurite optical glasses I. - Glass formation, structural, thermal and optical properties

The present study investigates the glass-forming ability (GFA), structural, thermal, and optical properties of the TeO2–BaO–Bi2O3 (TeBaBi) glass system, focusing on the mutual substitution trends of its constituent compounds. Prepared glasses were synthesized by the melt-quenching method at 900 °C and the GFA was extended by chemical compositions with lower TeO2 (55–85 mol.%) and higher Bi2O3 (5–15 mol.%) content via optimization of the synthesis process. The introduction of BaO and/or Bi2O3 results in the increase of the glass transition temperature (Tg≈327–384°C), molar volume (Vg≈28.9–33.1cm3mol−1) and optical basicity (OB≈0.97–1.03). Prepared TeBaBi glasses exhibit satisfactory thermal stability and wide spectral region of optical transparency from 0.4–6.5 μm with observed narrowing of optical window with higher TeO2 content. Compositional evolution of Tg may be described for the TeBaBi glasses using multilinear regression analysis with high correlation (r≥0.995) across the whole GFA region. The structure of studied TeBaBi glasses was investigated by Raman scattering and directly compared to the TeO2–ZnO–BaO (TZB) glass system prepared and characterized under identical conditions. Structural analysis revealed a similar degree of internal glass structure transformation regardless of whether a divalent zinc cation or trivalent bismuth cation is present.

A three-layer Hele-Shaw problem driven by a sink

In this paper, we investigate a sink-driven three-layer flow in a radial Hele-Shaw cell. The three fluids are of different viscosities, with one fluid occupying an annulus-like domain, forming two interfaces with the other two fluids. Using a boundary integral method and a semi-implicit time stepping scheme, we alleviate the numerical stiffness in updating the interfaces and achieve spectral accuracy in space. The interaction between the two interfaces introduces novel dynamics leading to rich pattern formation phenomena, manifested by two typical events: either one of the two interfaces reaches the sink faster than the other (forming cusp-like morphology), or they come very close to each other (suggesting a possibility of interface merging). In particular, the inner interface can be wrapped by the other to have both scenarios. We find that multiple parameters contribute to the dynamics, including the width of the annular region, the location of the sink, and the mobilities of the fluids.

Nonresonant central exclusive production from CMS+TOTEM

The central exclusive production of charged hadron pairs in pp collisions at a center-of-mass energy of 13[Formula: see text]TeV is examined, based on data collected in a special high-[Formula: see text] run of the LHC. Events are selected by requiring both scattered protons detected in the TOTEM Roman pots, exactly two oppositely charged identified particles in the CMS silicon tracker, and the energy–momentum balance of these four particles. The nonresonant continuum processes are studied with the invariant mass of the centrally produced two-pion system in the resonance-free region, [Formula: see text][Formula: see text]GeV or [Formula: see text][Formula: see text]GeV. Differential cross sections as functions of the azimuthal angle between the surviving protons, squared four-momenta, and two-hadron invariant mass are measured in a wide region of scattered protons with transverse momentum between 0.2 and 0.8[Formula: see text]GeV and for pion rapidities [Formula: see text]. A rich structure of interactions related to double pomeron exchange emerges. The parabolic minimum in the distribution of the two-proton azimuthal angle is observed for the first time. It can be understood as an effect of additional pomeron exchanges between the protons, and of the interference between the bare and the rescattered amplitudes. After model tuning, various physical quantities related to the pomeron cross section, proton–pomeron and hadron–pomeron form factors, trajectory slopes and intercepts, as well as coefficients of diffractive eigenstates of the proton are determined.

Study of direct and indirect risk assessment of landslide impacts on ultrahigh-voltage electricity transmission lines

Ultrahigh-voltage electricity systems are a vital part of energy networks, often across wide regions passing through mountainous terrains. The instability of slopes forming tower foundations along transmission lines poses a large risk to the entire energy network. Moreover, the tower foundations along extra-high-voltage electricity transmission lines are a very special type of element that are also highly vulnerable to landslides. In this study, an integrative risk assessment framework, including a hazard assessment, vulnerability analysis for the specified element at risk, and consequence estimation, is proposed to quantify the direct and indirect risks of landslides to power transmission lines. The Yanzi landslide, where a tower of the major ultrahigh-voltage transmission line from Sichuan (western China) to Shanghai (eastern China) has just been constructed, is taken as a case study. The correlation between landslide displacement and tower structure tilting is studied. In terms of the precipitation return period, factors of safety, failure probability, and deformation are simulated. A physical vulnerability curve is fitted by assuming a Weibull relationship between the horizontal deformation (hazard intensity) of the landslide and the tower inclination ratio. The total risk is calculated as the sum of the direct and indirect losses, among which the potential indirect risk due to tower damage is much greater than the direct risk. This work demonstrates the importance of landslide treatment strategies along electricity transmission lines by considering the potential indirect risks. The risk assessment model of landslides affecting ultrahigh-voltage electricity transmission lines proposed in this study could be useful for other types of indirect landslide risk evaluations.

The Impact of the Russia-Ukraine Conflict on Global Economic Stability and Political Security

The conflict between Russia and Ukraine has emerged as a significant geopolitical tension, with far-reaching implications for global stability and security. This paper intends to study the impact of the war on the worlds and regional economic development and political stability, and achieve some findings that may trigger further policy considerations in mitigating challenges and issues imposed by the war. Through literature reviews and comparison analysis, the findings reveal economic, political, and security consequences of the conflict. The disruption of trade flows, economic sanctions, and uncertainty have impacted both Russia and Ukraine, as well as the wider region and the world. Energy security concerns and shifts in military alliances have added to the complexity of the conflict. The expansion of NATO and increased rivalries between Russia and Western countries have further heightened tensions. Based on the findings, the paper concludes that the Russia-Ukraine conflict poses a significant threat to global economic stability and political security. It emphasizes the need for a multilateral approach to address the conflict and promote peace and stability in the region. Ceasefire agreements, humanitarian assistance, and reconstruction efforts are crucial steps towards long-term peace and development. The paper highlights the importance of prioritizing diplomatic solutions over short-term gains from the conflict. In summary, this paper intends to explore the implications of the Russia-Ukraine conflict on global stability and security, with findings that underscore the need for international cooperation and concerted efforts to mitigate the consequences of the conflict and foster a peaceful resolution.

Influence of ultrasonic assistance on the microstructure and friction properties of laser cladded Ni60/WC composite coatings

The effects of different ultrasonic vibration powers on the distribution, phase structure, friction and wear properties of WC reinforced particles in laser melted Ni60/WC composite coatings are investigated. The effects of ultrasonic vibration on the microstructure, elemental distribution, crystal orientation, friction and wear properties of the fused coatings are analyzed. The experimental results show that the deposition of WC particles in the lower and middle parts of the coating is significantly improved after the introduction of ultrasonic vibration during the fusion cladding process. In particular, at 600 W ultrasonic power, not only the distribution uniformity of tungsten carbide particles in the coating is optimal, but also the composite coating shows better wear resistance. However, too much ultrasonic power increases the possibility of particle agglomeration. In addition, although the phase pattern of the coating does not change after ultrasonic vibration, the width of the columnar crystalline region of the coating is reduced, and the coating is covered by a homogeneous lamellar nanoscale eutectic structure with the phase compositions of the γ-(Fe, Ni) and M23C6 phases. The ultrasonic vibration improves elemental segregation of the coating, reduces the large number of precipitated phases in the coating, weakens the grain growth orientation, and relieves the local stress concentration in the coating. In addition, the mechanism of the influence of WC particles on the microstructure evolution and wear resistance of the composite coatings is discussed.

Laser modulation to plateau region and intensity of high-order harmonic generation in monolayer MoTe2

Abstract Through solving semiconductor Bloch equations, we theoretically investigated the high-order harmonic generation in monolayer MoTe2 under laser modulation. Adjusting the laser parameters, the plateau region and intensity of harmonics can be effectively regulated. Changing laser wavelength can regulate the width of platform region and the cutoff order of harmonic spectrum. Platform region widens with the increase of laser wavelength. Under different laser wavelengths, the number of photons that need to be absorbed for electron transition varies, which affects the inter-band transition of electrons. Laser vector potential also varies with the wavelength, affecting the intra-band motion of electrons. Laser field strength can significantly change the harmonic intensity. As the laser field strength increases, the harmonic intensity increases and may generate new plateau in the high-energy region. The emergence of new platform is due to the transition of electrons between conduction bands. Our work provides a theoretical exploration for generating high quality harmonics and understanding the micro mechanism of high-order harmonic generation.&amp;#xD;

Achieving High Doping Density in pH-neutral Conjugated Polyelectrolyte Toward Effective Hole-Transporting Materials for Organic Solar Cells.

The lack of effective and non-corrosive hole-transporting layer (HTL) materials has remained a long-standing issue that severely restricts the performance of organic solar cells (OSCs). Most pH-neutral conjugated polyelectrolytes (CPEs) exhibit inferior performance to the acid-doped HTL materials due to their low doping density. In this study, a series of pH-neutral CPEs is designed and synthesized with high doping density as HTL materials. Through an elaborate synthetic route, two sulfonate-terminating alkoxyl side chains can be introduced into thiophene, by which the electron-rich, highly soluble, and chemically stable thiophene monomer is synthesized to enable the subsequent polymerization. The CPE PTT-F exhibit a remarkable self-doping property with an enhanced doping density from 2.01 × 1017 to 7.02 × 1018 cm-3. The high work function and the increased doping density of PTT-F-based HTL decrease the depletion region width from 38.4 to 8.1nm at the anode interface, which minimized the energy loss in hole transport. Consequently, a binary OSC modified by PTT-F-based HTL achieve a high PCE of 18.8%. To the best of the knowledge, this is the highest PCE for OSC employing CPE-based HTL. The results from this work demonstrate an encouraging achievement of realizing exceptional hole collection ability in pH-neutral CPEs.

Secondary vertex reconstruction with MaskFormers

In high-energy particle collisions, the reconstruction of secondary vertices from heavy-flavour hadron decays is crucial for identifying and studying jets initiated by b- or c-quarks. Traditional methods, while effective, require extensive manual optimisation and struggle to perform consistently across wide regions of phase space. Meanwhile, recent advancements in machine learning have improved performance but are unable to fully reconstruct multiple vertices. In this work we propose a novel approach to secondary vertex reconstruction based on recent advancements in object detection and computer vision. Our method directly predicts the presence and properties of an arbitrary number of vertices in a single model. This approach overcomes the limitations of existing techniques. Applied to simulated proton-proton collision events, our approach demonstrates significant improvements in vertex finding efficiency, achieving a 10% improvement over an existing state-of-the-art method. Moreover, it enables vertex fitting, providing accurate estimates of key vertex properties such as transverse momentum, radial flight distance, and angular displacement from the jet axis. When integrated into a flavour tagging pipeline, our method yields a 50% improvement in light-jet rejection and a 15% improvement in c-jet rejection at a b-jet selection efficiency of 70%. These results demonstrate the potential of adapting advanced object detection techniques for particle physics, and pave the way for more powerful and flexible reconstruction tools in high-energy physics experiments.

Deep Learning for Generating Time-of-Flight Camera Artifacts.

Time-of-Flight (ToF) cameras are subject to high levels of noise and errors due to Multi-Path-Interference (MPI). To correct these errors, algorithms and neuronal networks require training data. However, the limited availability of real data has led to the use of physically simulated data, which often involves simplifications and computational constraints. The simulation of such sensors is an essential building block for hardware design and application development. Therefore, the simulation data must capture the major sensor characteristics. This work presents a learning-based approach that leverages high-quality laser scan data to generate realistic ToF camera data. The proposed method employs MCW-Net (Multi-Level Connection and Wide Regional Non-Local Block Network) for domain transfer, transforming laser scan data into the ToF camera domain. Different training variations are explored using a real-world dataset. Additionally, a noise model is introduced to compensate for the lack of noise in the initial step. The effectiveness of the method is evaluated on reference scenes to quantitatively compare to physically simulated data.