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The excessive extraction of river sand has led to significant ecological issues. Moreover, the environmental impact and resource demand of cement production have increasingly turned the spotlight on sea sand as a viable alternative due to its abundance and ease of extraction. Concurrently, alkali-activated binders, a novel type of low-carbon cementitious material, have gained attention for their low energy consumption, high durability, and effective chloride ion fixation capabilities. However, they are susceptible to carbonation. Introducing a controlled sea sand amount can raise the materials’ carbonation resistance, although carbonation may raise the concentration of free Cl− within the structure to levels that could risk the integrity of steel reinforcements by accelerating corrosion. In this context, the current study investigates sea sand alkali-activated slag (SSAS) concrete prepared with varying water–binder (W/B) ratios to evaluate its impact on flowability, mechanical strength, performances, and chloride ion distribution post-carbonation. The results demonstrate that the mechanical property of SSAS concrete diminishes as the water-to-binder ratio increases, with a more pronounced reduction observed. The depth of carbonation in mortar specimens also rises with the W/B ratio, whereas the compressive strength post-carbonation initially decreases before showing an increase as carbonation progresses. Furthermore, carbonation redistributes chloride ions in SSAS, leading to a peak Cl− concentration near the carbonation front. However, this peak amplitude does not show a clear correlation with changes in the W/B ratio. This study provides a theoretical foundation for employing sea sand and alkali-activated concrete.

Gamma-ray continuum at > 10 MeV photon energy yields information on ≳ 0.2  – 0.3 GeV/nucleon ions at the Sun. We use the general-purpose Monte Carlo code FLUktuierenden KAskade (FLUKA) to model the transport of ions injected into thick and thin target sources, the nuclear processes that give rise to pions and other secondaries and the escape of the resulting photons from the atmosphere. We give examples of photon spectra calculated with a range of different assumptions about the primary ion velocity distribution and the source region. We show that FLUKA gives results for pion decay photon emissivity in agreement with previous treatments. Through the directionality of secondary products, as well as Compton scattering and pair production of photons prior to escaping the Sun, the predicted spectrum depends significantly on the viewing angle. Details of the photon spectrum in the ≈ 100 MeV range may constrain the angular distribution of primary ions and the depths at which they interact. We display a set of thick-target spectra produced making various assumptions about the incident ion energy and angular distribution and the viewing angle. If ions are very strongly beamed downward, or ion energies do not extend much above 1 GeV/nucleon, the photon spectrum is highly insensitive to details of the ion distribution. Under the simplest assumptions, flares observed near disc centre should not display significant radiation above 1 GeV photon energy. We give an example application to Fermi Large Area Telescope data from the flare of 12 June 2010.

Extensive and unregulated groundwater extraction for irrigation in the arid inland basins of Northwest China has led to a continuous increase in groundwater depth in agricultural irrigation areas. This has significantly altered the distribution of soil ions, making it difficult to predict their evolution and dynamic patterns. In this study, we used a space-for-time substitution approach to elucidate the evolution of the soil ion distribution under changing groundwater depths. Experiments were conducted in three typical irrigation areas with varying groundwater depths, that is, below 5 m, 5–10 m, and above 10 m in Korla, Xinjiang, China. Soil samples were collected from five profiles at depths of 0–180 cm to measure the soil moisture, salinity, and major ion content. An innovative research framework was developed to examine the relationship between groundwater depth and soil ion distribution using ion ratios, principal components, hierarchical clustering, and correlation analyses. This framework aims to reveal the dynamics, correlations, and mechanisms of soil moisture, salinity, ion distribution, and representative ion composition as groundwater depth increases in the arid agricultural irrigation areas of Northwest China. The results showed that as groundwater depth increased, the soil chemical type shifted from Ca-SO4 to Na-SO4 and mixed types, with an increase in SO42− and Na+ content in the soil profile. Soil moisture, salinity, sodium adsorption ratio (SAR), and total dissolved solids (TDS) were significantly higher in shallow groundwater than in deep groundwater. Groundwater depth was negatively correlated with soil moisture, salinity, and major cations and anions (K+, Na+, Ca2+, Mg2+, Cl−, SO42−, and NO3−). Meanwhile, a positive correlation exists between groundwater depth and CO32−. The dynamic distribution of soil ions is primarily governed by groundwater depth and is influenced by multiple factors. Evaporation is the dominant factor in shallow groundwater areas, whereas the mineral composition of rocks plays a crucial role in deep groundwater areas. These findings provide scientific support for strategic agricultural water-resource management policies and sustainable development strategies in arid regions.

To identify the key indicators for salt tolerance evaluation of Salix matsudana Koidz, we explored the relationship of ion absorption and distribution with chlorophyll, fluorescence parameters (leaf performance index, maximum photochemical efficiency), and photosynthetic gas parameters (net photosynthetic rate, transpiration, stomatal conductance, intercellular carbon dioxide concentration) under salt stress. We established 4 treatment groups and one control group based on salinity levels of NaCl hydroponic solutions (171, 342, 513, and 684 mm). The Na + /K + , Na + /Ca 2+ , chlorophyll fluorescence, and photosynthetic parameters of leaves were measured on the 1st, 3rd, 5th, 8th, 11th, and 15th days to analyze the correlations of chlorophyll, chlorophyll fluorescence and photosynthetic parameters to the ion distribution ratio. The results showed that (1) The ratio of the dry weight of roots to leaves gradually increased with increasing salt concentration, whereas the water content of leaves and roots first increased and then decreased with increasing time. (2) The content of Na + , Na +/ K + , and Na + /Ca 2+ in roots and leaves increased with increasing salt stress concentration and treatment time, and the difference gradually narrowed. (3) Ca 2+ was lost more than K + under salt stress, and Na + /Ca 2+ was more sensitive to the salt stress environment than Na + /K + . (4) Because the root system had a retention effect, both Na + /K + and Na + /Ca 2+ in roots under different NaCl concentrations and different treatment times were higher than those in leaves, and Na + /Ca 2+ was much higher than Na + /K + in roots. (5) Na +/ K + had a higher correlation with fluorescence parameters than Na + /Ca 2+ . Among them, Na + /K + had a significantly negative correlation with the maximum photochemical efficiency, and the correlation coefficient R 2 was 0.8576. (6) Photosynthetic gas parameters had a higher correlation with Na + /Ca 2+ than with Na + /K + . Among them, significantly negative correlations were noted between Na + /Ca 2+ and Gs as well as between Na + /Ca 2+ and E under salt stress. The correlation between Na + /Ca 2+ and Gs was the highest with a correlation coefficient of 0.9368. (7) Na + /K + and Na + /Ca 2+ had no significant correlation with chlorophylls. Na + /Ca 2+ was selected as a key index to evaluate the salt tolerance of S. matsudana Koidz, and the results provided a reference for analyzing the relationship between ion transport and distribution for photosynthesis.

The vertical neutron camera (VNC) is an ITER diagnostic system aimed at measuring the spatial distribution of the plasma neutron radiation intensity in the polloidal section, neutron flux, synthesis reaction power density, and alpha source profiles. In this article, we report the results of calculating the pulse-height spectra of ITER VNC diamond detectors with regard to the plasma ion distribution function. In most ITER plasma scenarios, an ion beam used to heat the plasma generates a population of superthermal ions with an anisotropic ion energy distribution function. The angular and energy distributions of neutrons generated in the plasma have been calculated for an arbitrary ion energy distribution function. For different ITER plasma scenarios, the change in the shape of the pulse-height spectra of VNC diamond detectors has been considered with and without taking account of neutrons arising in fusion reactions between superthermal and thermal ions. Based on calculation data, the influence of a neutral atom injection system on the readings of VNC detectors in measurements with deuterium and a deuterium–tritium plasma has been studied. The feasibility of recovering the spectrum of neutrons arising in reactions between thermal and superthermal ions in the plasma by analyzing the pulse-height spectra of VNC diamond detectors has been demonstrated for a deuterium plasma and a low-density deuterium–tritium plasma.

Within the framework of a one-dimensional two-component MHD model of plasma with hot electrons and cold ions, an analytical expression is obtained that describes the ion energy distribution functions, perturbed by ion-acoustic solitons. The calculations used both averaging over an ensemble of ions and time-averaging for a single ion. It is shown that ion-acoustic solitons strongly influence the ion distribution function, deviating it from the initial equilibrium state. After the passage of the soliton, the distribution function returns to its original state. Using the Korteweg-de Vries equation, an explicit formula for describing the perturbed distribution function is obtained, which can be applied in practice. A practically important situation of propagation of a large ensemble of solitons of different amplitudes is considered. The cases of small and large time resolution in measuring distribution functions are modeled in detail. The obtained theoretical results are compared with known experimental data.

The growing demand for lithium batteries with higher energy densities requires new electrode chemistries. Lithium metal is a promising candidate as the anode material due to its high theoretical specific capacity, negative electrochemical potential and favorable density. However, during cycling, low and uneven lithium ion concentration on the surface of anode usually results in uncontrolled dendrite growth, especially at high current densities. Here we tackle this issue by using lithiophilic montmorillonite as an additive in the ether-based electrolyte to regulate the lithium ion concentration on the anode surface and thus facilitate the uniform lithium deposition. The lithiophilic montmorillonite demonstrates a pumping feature that improves the self-concentrating kinetics of the lithium ion and thus accelerates the lithium ion transfer at the deposition/electrolyte interface. The signal intensity of TFSI − shows negligible changes via in situ Raman tracking of the ion flux at the electrochemical interface, indicating homogeneous ion distribution, which can lead to a stable and uniform lithium deposition on the anode surface. Our study indicates that the interfacial engineering induced by the lithiophilic montmorillonite could be a promising strategy to optimize the lithium deposition for next-generation lithium metal batteries. The address one of the major challenges facing the lithium metal anode, here the authors use lithiophilic montmorillonite as an additive to the ether-based electrolyte to regulate the lithium ion concentration on the anode surface, facilitating uniform lithium deposition.

The mineral surface structure and ions’ interaction were of significant interest to understanding mineral dissolution and reaction. In this study, X-ray photoemission spectroscopy combined with ICP emission spectrometer was used to investigate the influence of the leaching reaction conditions of 8 M dilute sulfuric acid and 12 M concentrated sulfuric acid on the surface chemical composition, chemical (valence) state and ion distribution of Columbite-(Fe) (FeNb2O6). The binding energy of the cations (Fe, Nb) bonding with different anions (O2−, SO42−) and the ratio of Fe3+/Fe2+ oxidation–reduction provided direct understanding of Fe and Nb releasing from the mineral surface during leaching. The results showed that the binding energy of the Nb5+-O bond was much smaller than that of Nb5+-SO4, and the binding energy decreased in sequence as Nb5+-O < Fe2+-O < Fe3+-O and increased in sequence as Fe3+-SO4 < Fe2+-SO4 < Nb5+-SO4. The mineral surface reaction during the leaching could be expressed with the formula: Fe-O + H2SO4 → Fe-SO4 + H2O, Nb-O + H2SO4 → Nb-SO4 + H2O. The results also revealed that Nb dissolution from Columbite-(Fe) occurred more easily compared to Fe. Nb dissolution from the mineral was owed to the content of H+ in solution, and increasing the H+ concentration could promote the dissolution. For Fe dissolution from the mineral, the oxidation potential could play an effective role in enhancement dissolution.

Plasmas of a variety of types can be described by the collisional radiative (CR) model developed by Colombant and Tonan. From the CR model, the ion distribution of a plasma at a given electron temperature and density can be found. This information is useful for further simulations, and due to this, the employment of a suitable CR model is important. Specifically, ionization bottlenecks, where there are enhanced populations of certain charge states, can be seen in these ion distributions, which in some applications are important in maintaining large amounts of a specific ion. The present work was done by implementing an accepted CR model, proposed by Colombant and Tonon, in Python and investigating the effects of variations in the ionization energy and outermost electron subshell occupancy term on the positions of ionization bottlenecks. Laser Produced Plasmas created using a Nd:YAG laser with an electron density of ∼ne = 1021 cm−3 were the focus of this work. Plots of the collisional ionization, radiative recombination, and three-body recombination rate coefficients as well as the ion distribution and peak fractional ion population for various elements were examined. From these results, it is evident that using ionization energies from the NIST database and removing the orbital occupancy term in the CR model produced results with ionization bottlenecks in expected locations.

All-solid-state Li batteries (ASSBs) employing inorganic solid electrolytes offer improved safety and are exciting candidates for next-generation energy storage. Herein, we report a family of lithium mixed-metal chlorospinels, Li 2 In x Sc 0.666− x Cl 4 (0 ≤  x  ≤ 0.666), with high ionic conductivity (up to 2.0 mS cm −1 ) owing to a highly disordered Li-ion distribution, and low electronic conductivity (4.7 × 10 −10  S cm −1 ), which are implemented for high-performance ASSBs. Owing to the excellent interfacial stability of the SE against uncoated high-voltage cathode materials, ASSBs utilizing LiCoO 2 or LiNi 0.85 Co 0.1 Mn 0.05 O 2 exhibit superior rate capability and long-term cycling (up to 4.8 V versus Li + /Li) compared to state-of-the-art ASSBs. In particular, the ASSB with LiNi 0.85 Co 0.1 Mn 0.05 O 2 exhibits a long life of >3,000 cycles with 80% capacity retention at room temperature. High cathode loadings are also demonstrated in ASSBs with stable capacity retention of >4 mAh cm −2 (~190 mAh g −1 ). Intensive research is underway to develop solid-state electrolytes for rechargeable batteries. Here the authors report a family of mixed-metal halospinel electrolytes that exhibits promising properties for high-performance solid-state batteries.