Water Interactions Research Articles

Assessing the resilience of stormwater ponds under climate change: A case study on Grace Lake, Florida, unveiling flood control and water quality implications

Stormwater ponds have emerged as a crucial solution in Florida to accommodate excess runoff from new developments and mitigate environmental pollution. Climate change affects rainfall and evapotranspiration, likely altering the hydrologic process. It is unclear how effective stormwater ponds will be in a changing climate, especially where surface water and groundwater interaction is highly expected. To address these concerns, this study employs a fully coupled surface water and groundwater model that was calibrated for the Grace Lake, located in central Florida. Utilizing the Multi-Model Ensemble method and GCM data, future rainfall projections were generated for the mid-century (2040–2070). The results indicate a projected 13 % increase in rainfall for the mid-century under the Representative Concentration Pathway 4.5 (RCP 4.5). This increase led to a rise of 13 cm in the seasonal high water elevation of Grace Lake, reducing its reliability as a flood control mechanism by 13 %. Moreover, downstream areas from the lake are expected to experience higher flood stages in the future, with the duration of road flooding extending from less than three days (base period) to approximately seven days (future period). This increase in surface runoff raises concerns for water quality, with nitrogen and phosphorus loads projected to surge up to 67 % in the future period.

T 1 Relaxation of Methane in Mixtures with Gaseous Water.

Synthetic, ecofriendly fuels and chemicals can be produced through Power-To-X (PtX) processes. To study such catalytic processes operando and spatially resolved, magnetic resonance imaging (MRI) is a versatile tool. A main issue in the application of MRI in reactive studies is a lack of knowledge about how the gathered signals can be interpreted into reaction data like temperature or species concentration. In this work, the interaction of methane and gaseous water is studied regarding their longitudinal relaxation time T 1 and the chemical shift. To this end, defined quantities of methane-water mixtures were sealed in glass tubes and probed at temperatures between 130 and 360 °C and pressures from 6 to 20 bar. From the obtained T 1 relaxation times, the collision cross section of methane with water σ j,CH4-H2O is derived, which can be used to estimate the temperature and molar concentration of methane during the methanation reaction. The obtained T 1 relaxation times can additionally be used to improve the timing of MRI sequences involving water vapor or methane. Further, details about the measurement workflow and tube preparation are shared.

Biopolymer composites based on ultrasound/plasma‐modified fiber waste and polybutylene adipate terephthalate (PBAT): Physicochemical and functional performance

AbstractA strategy for a circular economy is to reuse and modify agricultural wastes through green methodologies, which can be employed as high‐value raw materials to produce sustainable materials. Thus, polybutylene adipate terephthalate (PBAT) composites containing plasma (P) and ultrasound/plasma (UP) modified Agave fibers (AF) were prepared by the melt mixing process. The effect of content (10% and 20%) and type of fiber on the processing, structural, mechanical, and water barrier performance of PBAT composites was assessed. FTIR analysis exhibited the presence of O‐Si‐O groups in all composites containing modified AF, indicating the presence of nanometric hexamethyldisiloxane (HMDSO) coating on the fiber surface. The addition of modified AF into PBAT polymer promoted higher torque levels and specific energy during the composites processing, indicating higher matrix‐fiber interactions that hindered the free flow of the polymeric chains. Nevertheless, SEM, DSC, and crystallinity results revealed that PBAT‐AFUP composites exhibited more homogeneous surfaces and ordered structures that promoted higher entanglement between modified fibers and the PBAT matrix and restricted the binding sites for water interaction as changes in tensile modulus (from 90 to 163 MPa) and water contact angle (from 63 to 77°) indicated. These findings show that modified Agave fibers are a sustainable raw material that can be easily processed to produce soft and hydrophobic PBAT‐based composites.Highlights The fiber type determined the functional performance of the PBAT composites The modified fibers increased the entanglement of composite chains UP‐modified fibers improved the water barrier performance of the PBAT matrix

A theoretical investigation of water adsorption on the compressed (001) surface of kaolinite under pressure

The interaction of kaolinite and water has been extensively investigated by scholars in geomechanics and high-pressure physics fields. As well known, the effects of pressure on the adsorption capacity of clay mineral cannot be ignored. In the present paper, the adsorption behaviors of water molecules with different coverage (0 ≤ Θ ≤ 1 ML) on the kaolinite (001) surface under the pressure range of 0–10 GPa were examined using density functional theory (DFT). The atomic structure of kaolinite has undergone phase transitions under high pressure. The transition pressures of kaolinite occurred at 4.93 GPa (kaolinite-I → kaolinite-II) and 8.23 GPa (kaolinite-II → kaolinite-III), respectively. The results revealed that the hollow sites of kaolinite-Ⅰ, Ⅱ, and Ⅲ (001) surface were the most stable adsorption sites for water molecules at different coverages. The order of adsorption capability for three phases kaolinite was kaolinite-Ⅰ > kaolinite-Ⅱ > kaolinite-Ⅲ. In the pressure range of 0∼10 GPa, the adsorption energies of water molecules on the three phases of kaolinite (001) surfaces increased with increasing coverage (0 ≤ Θ < 1/2 ML) and then decreased with increasing coverage (1/2 < Θ ≤ 1 ML). For three phases kaolinite, the adsorption energies decreased with increasing pressure at 1/16 and 1/4 ML, while the changes of adsorption energies at other coverages with increasing pressure didn't exhibit obvious consistent regularity. Further exploration was performed on the structure and electronic properties change within the adsorption process by studying the lattice relaxation, and electronic density of states (DOS) of the adsorption system of (001) surface and water molecules.

Changes in conditions of interaction of ground, river and swamp water during swamping of the West Siberian plain in the Holocene

Relevance. The need to understand and long-term forecast the conditions of interaction between groundwater, river and swamp waters in the Ob River basin. Aim. To identify patterns of changes in the conditions of interaction of groundwater, river and swamp waters during swamping of the flat part of the Ob River basin in the Holocene. Methods. Mathematical modeling methods, statistical methods, geographical-hydrological method. Results and conclusions. The author has carried out an analysis of materials from long-term hydrogeological and hydrological observations in the wetlands of the Ob basin and studied the hydrodynamic and geochemical conditions for interaction of groundwater, river and swamp waters. It is shown that the emergence and evolution of swamp ecosystems in the territory under consideration is a complex of erosion-accumulation processes, the development of which until the modern period took place in three stages: 1) from the beginning of intense degradation of glaciation to 4...6 thousand years ago is the formation of a primary hydrographic network approximately modern appearance, distribution of peat bogs; the groundwater regime is close to the groundwater regime of the permafrost zone in the north of modern Western Siberia; 2) from 4...6 thousand years ago to 1.5...3 thousand years ago is large-scale distribution of lowland swamps and degradation of part of the primary river network; groundwater levels in river watersheds are generally lower than at present, but the amplitude of their fluctuations is high; a significant part of the watersheds are flooded during high water and floods, and underflooded during low water periods; 3) from 1.5...3 thousand years ago is degradation of a significant part of the primary river network, wide distribution of raised swamps, formation of a secondary hydrographic network in the swamps; at watersheds, groundwater levels rise, but the amplitude of their fluctuations decreases, and water exchange with swamps is significantly reduced; in the valleys of medium and large rivers, water exchange between surface and groundwater is most intense, which causes the flow of significant amounts of organic substances and products of their transformation into river and groundwater from swamps. Scenarios of possible changes in the conditions of interaction between surface and groundwater were assessed.

Evaluation of buoyant action of groundwater and surface water interaction on pit slope stability using hydrogeological-stratigraphic-structural assessment within the Kawere catchment of the Nsuta mine

ABSTRACT In open-pit mining operations where activities are conducted below water table or close to surface water bodies, the mine is potentially faced with dewatering and slope stability challenges. Appropriate evaluation of slope stability to obtain adequate slope safety factor has continuously been the centre of geotechnical research locally and internationally. This paper evaluates the influence of buoyant action propagated by groundwater and surface (GW-SW) interaction on pit slope designed in multi-layered fractured rock with complex hydrology using Hydrogeological-Stratigraphic-Structural Assessment (HSSA) at the Nsuta Manganese Mine in Ghana. LEM analyses of the Pit C-western slope estimated an overall factor of safety (FOS) of 1.1, probabilities of failure (POF) of 7.5% and the reliability index (RI) of 1.4 in the slope stress field. However, when the groundwater was introduced, the slope FOS was reduced to 0.13, POF of 100.0% and (RI) of 0.00 indicating failure. FEM numerical model points to the location of maximum shear strain and total displacement in the argillite zone within the rock mass. The FEM seepage analysis model estimated groundwater pore pressure data along the critical slide surfaces from the crest of the slope to the bottom of the rock slope ranging between 250 kPa and 4250 kPa with an average pore pressure of 2250 kPa within the pit slope. This proposed HSSA approach used in the study provides innovative insights into the percentage failure contribution of the individual lithologies to the overall combined lithological susceptibility of the slope under stress and groundwater failure mechanisms, pointing out Ru ratio in pit slope stability estimation as inadequate.

An integrated pretreatment strategy for enhancing enzymatic hydrolysis efficiency of poplar: Hydrothermal treatment followed by a twin-screw extrusion

To reduce the dependence on chemical inputs during biomass pretreatment, an integrated process on the basis of hydrothermal pretreatment followed by twin-screw extrusion for poplar was proposed. A comparative study was conducted on the pore structure, crystallinity, relative surface lignin concentration, cellulose accessibility, and enzymatic hydrolysis efficiency of the pretreated materials. Results suggested that the relative surface lignin concentration of fibers pretreated by hydrothermal treatment (conducted at 170 ℃ for 90 min) coupled with extrusion (HE) treatment was decreased compared to the sole hydrothermal (H) process, which had a positive impact on the subsequent enzymatic hydrolysis. Additionally, the HE process resulted in an increase in pore size by 34.4%, pore volume by 447.5%, and specific surface area by 93.5%, which enhanced the penetration and interaction of water into the fibers and thus increased cellulose accessibility by 143.2%. SEM and TEM observations revealed that fibers were separated and finely fibrillated, large amounts of fragmentary structure and cracks appeared on the fiber. In addition, the cell wall structure was deformed and damaged, when pretreated by HE process. Overall, this work showed that hydrothermal treatment followed by twin-screw extrusion was an achievable strategy for high fermentable sugar production of hardwood.

Fabrication of a robust zwitterionic coating on glass with anti-fogging, anti-frosting, self-cleaning and antibacterial properties via UV-induced grafting polymerization

In this work, glass slides were separately silanized by silane coupling agents, 3-(trimethoxysilyl) propyl methacrylate (TPM) and 3-(mercaptopropyl) trimethoxysilane (MPS). Then, in presence of a photoinitiator, multifunctional hydrophilic coatings were fabricated facilely on these silanized glasses via UV-induced grafting polymerization of zwitterionic acrylic monomer methacryloxyethyl sulfobetaine (SBMA). The results showed that both TPM and MPS silanized glasses could participate in the UV-induced grafting polymerization of SBMA, while more SBMA could be grafted to the former glass to gain a little bit higher hydrophilicity. The structure, morphology and properties of the multifunctional glasses were investigated fully. As the hydrophilic polymer brushes poly(SBMA) (pSBMA) covalently attached to the glass surface, the glasses could render a series of excellent performances, including underwater superoleophobicity, anti-fogging, anti-frosting, abrasion resistance, self-cleaning and antibacterial adhesion, and especially high stability even after being immersed in water for 20 days. The strong interaction of pSBMA and water was confirmed via differential scanning calorimeter (DSC) and Raman spectrum analysis, to explicit the anti-fogging mechanism. Therefore, it is promising that the scalable multifunctional glass fabricated via UV-induced grafting polymerization could be potentially applied in the fields of automobile, bathroom, medical, etc.

Seasonality of hydrogeochemical evolutions and isotopic variabilities (δ18O, δ2H and d-excess) in the surface water as well as groundwater from tropical central-south Mexico

Due to adverse impact of the global warming on hydrological resources, we intended to document the hydrogeochemical evolutions of surface and groundwater at tropical central-south Mexico in terms of seasonality of rock-water interaction, precipitation/evaporation variation and moisture source by evaluating the major ion chemistry in Piper and Gibbs plots, Durov diagram and through estimation of the chloro-alkaline indices as well as assessing the stable isotope compositions (δ18O and δ2H) in samples from different seasons of a year. Surface water of the Lake Coatetelco shifted from mostly Ca–Mg–HCO3 facies in wet summer-autumn to Na–HCO3–Cl facies in the dry spring due to elevated Na, Cl and HCO3. Greater evaporation in spring led to a maximum δ18O enrichment of ca.7‰ compared to the other seasons, and much depleted deuterium excess (−40.92‰ to −39.20‰). Interaction of the lake water with subsurface carbonate lithologies, and comparable isotopic compositions reflected the enhanced interaction between the surface water body and aquifers in the wet autumn. Effect of seasonality, however, was unclear on the groundwater facies, and its heterogenous composition (Ca–Mg–HCO3, Na–HCO3–Cl and Na–HCO3) reflected the interactions with different lithologies. Fractionations in isotope compositions of the groundwater were caused from recharge at different elevations, seasonality of moisture sources and moisture recycling. The water-mineral saturation index was an efficient proxy of seasonality as the lake water and groundwater (avg SIcalcite > 0.5) of the dry autumn were saturated with calcite. This vital information about carbonate precipitation, pCO2 and chemical facies would be useful for the better interpretation of paleoclimate archives in this region.

Water Uptake Characteristics of Stipa bungeana Trin: Affected by Subsidence in the Coal Mining Areas of Northwest China

Revealing the water use pattern of plants influenced by coal-mining-caused land subsidence is crucial to understand plant–water interactions and guide ecological restoration. However, available information on herbaceous plants, the dominant species in most arid and semi-arid regions with abundant coal resources, remains inadequate. We investigated the water use patterns of Stipa bungeana Trin. by measuring soil water content, root distribution, and stable isotopes of hydrogen (δ2H) and oxygen (δ18O) of soil water and plant stem water both before and after a rainfall event. The results revealed that prior to rainfall, both areas exhibited a low soil water content with no discernible difference in soil drought. However, the soil waters δ2H and δ18O were found to be more enriched at varying depths within the subsidence area, indicating a heightened level of soil evaporation. Both soil water content and soil water isotopic composition responded sensitively to rainfall, with rainfall primarily replenishing the shallow layer (0–20 cm), thereby reflecting an infiltration mode dominated by piston flow. More water seeped into deeper soil layers in the subsidence area compared to the non-subsidence area, with more preferential flow. Before rainfall, the sources of plant water uptake were consistent both at shallow and deep soil layers, implying that the proportion of water uptake gradually decreased with increasing depth. After rainfall, the sources of plant water uptake differed slightly between the two soil layers. The plants in non-subsidence and subsidence areas dominantly extracted soil water at depths greater than 10 cm and 20 cm, respectively. The root system in the subsidence area was more developed than that in the non-subsidence area. Plant water uptake was primarily influenced by the spatial distribution of roots, as well as the post-rainfall water distribution, regardless of whether they were in the subsidence area or not. Although land subsidence affected soil water transport, the water uptake pattern of Stipa bungeana Trin. was similar before and after rainfall, indicating the adaptive growth of plants through their roots in the subsidence area. The high adaptability of herbs such as Stipa bungeana Trin. makes them a viable option for vegetation restoration in subsidence areas. This study has significant implications for evaluating plant–water relationships in subsidence areas due to coal mining, thereby providing a fundamental basis and valuable reference for ecological restoration and management strategies within such affected regions.

Comparative Analysis of Water Isotopic Compositions: Evaluating Isotope Analyzer for Soil and Extraction Method for Stem Water

Stable isotopes of water (δ2H and δ18O) are reliable tracers for the investigation of plant–soil–water interactions in forest ecosystems. However, variations in isotopic compositions may arise due to differences in analytical instruments and water extraction methods. In this study, we conducted three different experiments to identify isotopic differences caused by analytical and methodological variations. First, we analyzed soil water by using the two most commonly applied methods: isotope ratio mass spectrometry (IRMS) and cavity ring-down spectroscopy (CRDS). Second, we compared the isotopes in xylem water extracted from the stems of nine tree species using cryogenic vacuum distillation (CVD) with different heating times. Third, we compared the compositions in xylem water extracted with three different methods: mechanical squeezing using a pressure chamber (PC), an induction module (IM), and CVD. The differences in isotopic composition between IRMS and CRDS were significant but minimal. Soil properties were not significant factors contributing to differences between the two instruments. For the xylem water extraction with CVD, each of the nine tree species required heating for more than three hours. Significant differences were observed in δ2H among the three extraction methods for xylem water. Xylem water extracted by CVD showed more depleted values compared to those obtained by PC and IM. Our results highlight the importance of considering analytical and methodological variations in stable isotope analysis.

Towards H2 production from water and ethanol interactions on hydrated TiO2(101): Insights from ReaxFF molecular dynamics

ReaxFF molecular dynamics is employed to investigate interactions between water, ethanol, their mixture, and hydrated TiO2(101) surfaces. Water maintains hydration, while exchanging both hydrogen and oxygen atoms with the surface. Ethanol dissociates, leading to the formation of ethoxy radicals (CH3CH2O) permanently attached to the surface, water molecules, and acetic acid (CH3CO2) species. Ethoxy reduces the number of hydroxyl groups and hinders hydrogen migration across the surface. The mixture of water, ethanol, and TiO2(101) results in a reduction of ethoxy coverage, inhibits CH3CO2 formation, and increases hydroxyl coverage, indicating the dominant role of water. Potential of mean force analysis shows that hydroxyl formation follows exothermic paths, with activation energy lower than 0.45 eV. A narrower pathway for ethanol access to its adsorbed site is a key factor in the dominance of water. The formation of H2 molecules exhibits a prohibitive energy barrier (>4 eV), suggesting that catalytic pathways, rather than purely surface reactions, could be favored.

Influence of citric acid concentrations on the porosity and performance of cellulose acetate-based porous membranes: A comprehensive study

This study investigates the influence of citric acid concentration on the fabrication of porous cellulose acetate (CA) membranes using the Non-Solvent Induced Phase Separation (NIPS) method. A notable aspect is the precise control over membrane properties, particularly pore size and porosity, achieved solely through the adjustment of citric acid concentration, serving as the additive. Higher concentrations of citric acid increase pore size by rendering polymer chains more pliable, whereas lower concentrations lead to smaller, denser pores due to improved dispersion in the CA matrix and altered water interactions during phase separation. A decrease in porosity and Gurley values with reducing citric acid concentrations (from 5 × 10−2 to 1 × 10−3 M ratios) indicates less plasticization of CA chains. However, at very low concentrations (1 × 10−4 and 1 × 10−5), porosity increases, despite the presence of smaller pores, and Gurley values approach those of pure CA in terms of gas permeability. Fourier Transform Infrared (FT-IR) spectroscopy confirms the presence of citric acid and its interaction with carbonyl groups, consistent with the pore size observations from Scanning Electron Microscopy (SEM). Spectral data deconvolution reveals weakened carbonyl bonds due to the reduced presence of citric acid, correlating with the smaller pores observed in SEM. Thermal Gravimetric Analysis (TGA) demonstrates that composite membranes are more thermally stable than pure CA, attributed to the citric acid-induced crosslinking within the polymer chains. Stability increases with decreasing citric acid concentration, with some anomalies at the lowest levels. In conclusion, this study highlights the capability of adjusting citric acid concentration to tailor membrane properties, offering valuable insights for the creation of porous materials across diverse industrial applications.

Ecological stoichiometry and adaptations to drought and nitrogen in Hevea brasiliensis and Dalbergia odorifera in different planting patterns

Two tropical forest trees (Dalbergia odorifera T. Chen and Hevea brasiliensis Muell. Arg), cultivated both in pure or mixed planting systems under drought and nitrogen-applied conditions, were selected at seedling stages as experimental materials to investigate their eco-physiological responses, interactions with neighboring trees, and the stoichiometry of carbon (C), nitrogen (N), and phosphorus (P). The results highlighted significant differences in biomass allocation between D. odorifera, which allocates more to root growth, and H. brasiliensis, favoring stem growth. It demonstrates that mixed planting enhances tree growth under well-watered conditions, while nitrogen application promotes growth across different moisture levels, with species-specific responses. Water and nitrogen interaction notably affects H. brasiliensis growth but less so for D. odorifera, revealing complex effects on their biochemical responses to oxidative stress. The mixed planting benefits both species, influencing nutrient dynamics and stoichiometry in D. odorifera. The study also shows that nitrogen application under well-watered conditions alters nutrient ratios, particularly affecting nutrient availability and competition between species in mixed planting setups. In conclusion, this research emphasizes the complex interplay between planting patterns, water, and nitrogen, which significantly impacts tree growth, nutrient dynamics, and stress responses, suggesting that specific management strategies could optimize forestry practices.

From Soy Waste to Bioplastics: Industrial Proof of Concept.

The global plastic waste problem is pushing for the development of sustainable alternatives, encouraged by stringent regulations combined with increased environmental consciousness. In response, this study presents an industrial-scale proof of concept to produce self-standing, transparent, and flexible bioplastic films, offering a possible solution to plastic pollution and resource valorization. We achieve this by combining amyloid fibrils self-assembled from food waste with methylcellulose and glycerol. Specifically, soy whey and okara, two pivotal protein-rich byproducts of tofu manufacturing, emerge as sustainable and versatile precursors for amyloid fibril formation and bioplastic development. An exhaustive industrial-scale feasibility study involving the transformation of 500 L of soy whey into ∼1 km (27 kg) of bioplastic films underscores the potential of this technology. To extend the practicality of our approach, we further processed a running kilometer of film at the industrial scale into transparent windows for paper-based packaging. The mechanical properties and the water interactions of the novel film are tested and compared with those of commercially used plastic films. By pioneering the large-scale production of biodegradable bioplastics sourced from food byproducts, this work not only simultaneously addresses the dual challenges of plastic pollution and food waste but also practically demonstrates the feasibility of biopolymeric building block valorization for the development of sustainable materials in real-world scenarios.

Exploring the air impacts on the state development of pipe flow using the smooth particle hydrodynamic method

Abstract It is widely recognized that the water flow in pipes can be affected by trapped air pockets. However, the underlying air–water interactions of free flow with non-jacking downstream of the pipe are rarely investigated. There are no studies at this time that clearly elucidate the differences in pipe flow between the vacuum and the presence of air in the free flow case. To this end, the smoothed particle hydrodynamics (SPH) method is applied to study the air–water hydraulic dynamics in the pipe under free flow. We perform SPH simulations in several different scenarios and find that (i) the SPH method is competent to simulate both single- and two-phase flows in the pipe due to its outstanding advantages in capturing complex interfaces; (ii) only when the upstream water level is higher than the top of the pipe inlet, and the water level in the pipe rises to the top of the pipe due to air resistance, can a full pipe flow be formed; and (iii) the presence of air can cause the water to form a full pipe flow, causing a siphon-like effect that promotes pipe drainage. These results provide insights into the underlying complex air–water hydraulic properties in pipe flows.

Sum-frequency triad interactions among surface waves propagating through an ice sheet

We study nonlinear resonant wave–wave interactions which occur when ocean waves propagate into a thin floating ice sheet. Using multiple-scale perturbation analysis, we obtain theoretical predictions of the wave amplitude evolution as a function of distance travelled past the ice edge for a semi-infinite ice sheet. The theoretical predictions are supported by a high-order spectral (HOS) method capable of simulating nonlinear interactions in both open water and the ice sheet. Using the HOS method, the amplitude evolution predictions are extended to multiple (coupled) triad interactions and a single ice sheet of finite length. We relate the amplitude evolution to mechanisms with strong frequency dependence – ice bending strain, related to ice breakup, as well as wave reflection and transmission. We show that, due to sum-frequency interactions, the maximum strain in the ice sheet can be more than twice that predicted by linearised theory. For an ice sheet of finite length, we show that nonlinear wave reflection and transmission coefficients depend on a parameter in terms of wave steepness and ice length, and can have values significantly different than those from linear theory. In particular, we show that nonlinear sum-frequency interactions can appreciably decrease the total wave energy transmitted past the ice sheet. This work has implications for understanding the occurrence of ice breakup, wave attenuation due to scattering in the marginal ice zone and the resulting ice floe size distribution.

Structure Discovery in Atomic Force Microscopy Imaging of Ice.

The interaction of water with surfaces is crucially important in a wide range of natural and technological settings. In particular, at low temperatures, unveiling the atomistic structure of adsorbed water clusters would provide valuable data for understanding the ice nucleation process. Using high-resolution atomic force microscopy (AFM) and scanning tunneling microscopy, several studies have demonstrated the presence of water pentamers, hexamers, and heptamers (and of their combinations) on a variety of metallic surfaces, as well as the initial stages of 2D ice growth on an insulating surface. However, in all of these cases, the observed structures were completely flat, providing a relatively straightforward path to interpretation. Here, we present high-resolution AFM measurements of several water clusters on Au(111) and Cu(111), whose understanding presents significant challenges due to both their highly 3D configuration and their large size. For each of them, we use a combination of machine learning, atomistic modeling with neural network potentials, and statistical sampling to propose an underlying atomic structure, finally comparing its AFM simulated images to the experimental ones. These results provide insights into the early phases of ice formation, which is a ubiquitous phenomenon ranging from biology to astrophysics.

Investigation of encapsulated water wire within self-assembled hydrophilic nanochannels, in a modified γ4-amino acid crystals: Tracking thermally induced changes of intermolecular interactions within a crystalline hydrate

Nanostructures formed by the self-assembly of modified/unmodified amino acids have the potential to be useful in several biological/nonbiological applications. In that regard, the greater conformational space provided by γ-amino acids, owing to their additional backbone torsional degrees of freedom and enhanced proteolytic stability, compared to their α-counterparts, should be explored. Though, modified single amino acid-based nanomaterials such as nanobelts or hydrogels are developed by utilizing the monosubstituted γ-amino acids derived from the backbone homologation of phenylalanine (Phe). Examples of a single γ-amino acid-based porous nanostructure capable of accommodating solvent molecules are not really known. The crystal structures of a modified γ4(R)Phe residue, Boc-γ4(R)Phe-OH, at different temperatures, showed that hydrogen-bonded water molecules are forming a wire inside hydrophilic nanochannels. The dynamics of intermolecular interactions between the water wire and the inner wall of the channel with relation to the temperature change was investigated by analyzing the natural bonding orbital (NBO) calculation results performed with the single crystal structures obtained at different temperature points. The NBO results showed that from 325 K onward, the strength of water–water interactions in the water wire are getting weaker, whereas, for the water–inner wall interactions, it getting stronger, suggesting a favorable change in the orientation of water molecules with temperatures, for the latter.

Analysis of Secondary Particles Produced by 50-500 MeV Muon and Water Interaction using PHITS Monte Carlo Package

Secondary particles will always be generated in particle-to-matter interactions. The interaction of muons with matter produces various secondary particles. In this study, secondary particles produced by the interaction between muons with energies of 5, 50, 100, 200 and 500 MeV with water were analyzed using the PHITS Monte Carlo package. The muon source is placed on the surface of water that has a thickness of 1 km. The muography technique was applied by placed a detector at a depth of 1 km from the source. This detector records the secondary particles produced by the interaction. The results obtained show that this interaction produces secondary particles in the form of photons and neutrons in the detector. The number and energy of these photons and neutrons are strongly influenced by the initial energy of the muon. Muons with the lowest energy of 5 MeV produce more secondary particles than any other energy by a factor of 10. Low-energy muons travel slowly, allowing more interactions to occur and increasing the number of secondary particles in the detector. The energies of neutrons and photons in the detector are at most 3.76 MeV and 5.3 MeV, respectively.