Surface Layer Research Articles

One‐Step Hydrothermal Process to Fabricate Hydrophobic Mg–Al Layered Double Hydroxide Coating on MAO–Coated AZ31 Magnesium Alloy and Its Durability

In order to improve the corrosion resistance of micro‐arc oxidation (MAO) ceramic layer of AZ31 magnesium alloy, a hydrophobic Mg–Al layered double hydroxide (LDH) coating was prepared on its surface by a one‐step hydrothermal method. The microstructure of the coating was characterized by scanning electron microscope, energy disperse spectroscopy, X‐ray diffractometer, and Fourier transform infrared spectrometer. The wettability and corrosion resistance of the coating were studied by contact angle (CA) measuring instrument and electrochemical workstation. Meanwhile, the durability of the coating was evaluated by sandpaper abrasion, tape peeling and immersion test. The results showed that the hydrophobic Mg–Al LDH coating can be successfully prepared on the surface of MAO ceramic layer by one‐step hydrothermal treatment with alkaline aluminum nitrate solution containing sodium laurate. The hydrophobic Mg–Al LDH coating sealed the inherent defects of MAO ceramic coating, resulting in significantly improved corrosion resistance. With the extension of sandpaper abrasion distance, tape peeling times, and immersion time, the CA of the coating shows a downward trend, and the coating gradually changed from hydrophobic to hydrophilic. However, after the durability test, the coating still has good corrosion resistance, and its corrosion current density was still lower than that of MAO ceramic layer.

On the reasons for the long-term variability of the dissolved oxygen concentration in the upper layer of the Black Sea

According to archival data for the period from 1923 to 2022 long-term (interdecadal and interannual) variability of dissolved oxygen concentration and temperature in the surface layer of the Black Sea in the spring hydrological season (from May to June) is analyzed. It was revealed that from 1923 to 1932 on the northwestern shelf and in the open part of the Black Sea, the lowest oxygen concentrations were observed over the entire period of instrumental observations (approximately 100 years). Negative anomalies in dissolved oxygen exceeded (in absolute value) the corresponding anomalies noted during the period of eutrophication of the Black Sea waters in the last decades of the 20th century. The main reason for the extreme anomalies discovered in the 1920s is the increase in the temperature of the surface layer of the Black Sea waters during this period.

Are rootzone soil moisture dynamics and thresholds associated with surface layer?

Abstract The identification of evapotranspiration regimes, primarily the water-limited and energy-limited regimes, separated by the critical soil moisture (CSM) threshold, is fundamental to analyzing land–atmosphere interactions. To better understand the soil moisture (SM) dynamics happening synchronously in the soil column, we aim to estimate the rootzone (0–28 cm and 0–100 cm) CSM thresholds and associated regimes at a global scale, which was not previously attempted. We propose the use of the covariability of soil diurnal temperature amplitude (derived from the GLDAS) and SM (ERA5) to estimate the CSM, which overcomes the data uncertainty and multivariate dependencies of traditional methods. We find that transitional climatic regions, encompassing the western USA, Brazilian savanna, Sahelian grassland, South African savanna, peninsular India, and Mediterranean region, are global hotspots of frequent rootzone regime shifting with significant seasonality—the wet regime prevails in the fall season, while the dry regime takes over at other times of the year. The CSM values of 0–28 cm and 0–100 cm layers are mostly in the 0.2–0.35 and 0.25–0.4 m3m−3 range, respectively. We find that landscape aridity and bioclimatic characteristics primarily determine the spatial distribution of CSM and associated regimes. Furthermore, we investigate the hydrological link between the surface and rootzone layers. We note that the rootzone and surface CSM and regimes are strongly correlated, although the 0–28 cm layer indicates a relatively stronger connection compared to the 0–100 cm layer. The shallower (deeper) rootzone layer shows regimes similar to those on the surface for more than 80% (65%–80%) of the time. We observe that the strength of association between surface and rootzone regimes increases from arid (herbaceous vegetated regions) to humid (woody) regions and during wet to dry seasons. Overall, a strong association in regime dynamics between surface and subsurface layers suggests the potential applicability of remotely sensed surface SM as a surrogate to study rootzone regime responsiveness to soil–plant–atmosphere interactions.

Composition of methane cycle microbial communities in the upper layers of bottom sediments of the Kara sea

A study of the distribution of methane cycle microbial communities in the upper layers of bottom sediments above large hydrocarbon reservoirs in the South Kara petroleum region of the West Siberian Province revealed the presence in these layers of both aerobic methanotrophic bacteria and anaerobic methanogenic archaea, as well as numerous heterotrophic microorganisms of various phylogenetic groups. Research was carried out in the Baydaratskaya Bay and in the east of the Pukhuchan Depression (southern part of the Kara Sea). Aerobic methanotrophic bacteria belonged to the families Methyloligellaceae, Methylophagaceae and Methylomonaceae were detected in the surface oxidized layers (0–2 cm, Eh from 60 to 175 mV) of bottom sediments. Moreover, representatives of Methyloligellaceae were found in quite significant amount (1.52–2.61 % of all 16S rRNA gene sequence reads) at all studied stations of the Kara Sea. In the subsurface reduced layers (18–20 cm, Eh from −63 to –246 mV), methanogenic archaea were dominated by representatives of the order Methanomassiliicoccales (up to 3.3 % of all 16S rRNA gene sequence reads). Methanogenic archaea of the orders Methanofastidiosales, Methanobacteriales and Methanomicrobiales were also discovered. In addition, aerobic/facultative anaerobic methanotrophic bacteria of the families Methylococcaceae and Methylomonadaceae were found on these reduced layers of the bottom sediments, but the relative abundance (in percentage of sequence reads of their total number) of anaerobic methanotrophic archaea was extremely low there. Apparently, the oxidation of methane in bottom sediments of the Kara Sea, where its concentration at most of the studied stations dramatically increased with sediment depth, occurs predominantly under aerobic conditions in the surface layers, where the relative abundance and phylogenetic diversity of methanotrophs is higher.

Research on the performance and strengthening mechanism of composite‐enhanced recycled aggregate concrete

AbstractThe application of recycled aggregate concrete (RAC) greatly promotes the sustainable development of engineering construction, and improving its performance can further expand its practical application range. In order to obtain higher performance RAC, this article selects two composite pre‐treatment methods: cement silica mortar wrapping organosilicon immersion, water glass soaking, and organic silicon soaking to enhance the performance of recycled aggregate (RA). Subsequently, the composite reinforced RAC was poured, and their mechanical and durability properties were tested. The strengthening mechanism of the composite pre‐treatment method was analyzed. The results show that compared with the single‐treatment method, the composite strengthening method has an effect of increasing the apparent density of RA by 0.2%∼4%, and the effects of reducing the crushing value and water absorption are increased by 0.5%∼7.2% and 0.4%∼4.7%, respectively; both composite strengthening methods can improve the mechanical and durability properties of RAC. Analysis of the samples using SEM, TG, and XRD showed that both composite strengthening methods filled the microcracks and pores on the surface of the old mortar layer of RA and promoted the hydration of cement in the transition zone between the RAC interfaces, thereby increasing the interface strength and improving the mechanical and durability properties of RAC.

Preparing Al2O3/TiO2 nano-multilayers on the surface of FeAl/Al2O3 coating as tritium permeation barrier

Abstract Preparing tritium permeation barrier (TPB) coating on the surface of structural materials can effectively alleviate tritium permeation in fusion reactor system. However, due to the existence of inevitable certain number of defects in TPB, there is still a gap between the commonly prepared TPB coatings and the requirements proposed by fusion reactors. In this work, composite coatings with Al2O3/TiO2 nano-multilayers (NMLs) covering on the surface of FeAl/Al2O3 coating were prepared as TPB. The FeAl/Al2O3 TPB coating on the surface of 316L stainless steel was prepared by electrochemical deposition of Al, aluminization and in-situ oxidation. Due to the aggregation of Cr, there are micro sized defects in the Al2O3 layer. The presence of defects seriously reduces its hydrogen isotopes permeation resistance. The atomic layer deposition was then adopted to prepare Al2O3/TiO2 NMLs with period thickness of 15, 7.5 and 3 nm on the surface of Al2O3 layer, which not only cover the defects, but also utilize interfaces to suppress hydrogen isotopes permeation. The composite coating sample with the period thickness of 3 nm showed great enhancement of two orders of magnitude in deuterium permeation resistance property compared to the original FeAl/Al2O3 TPB coating at 500 °C, and the permeation reduction factor reaches a high value of 5 × 105, which far above the requirements of future fusion reactors.

Computer-Integrated Surface Image Processing of Hydrogen-Saturated Steel Wear Products

This paper briefly describes the conceptual direction of the application of computer vision (CV) methods that involve controlling the morphology of hydrogenated wear particles (WPs). During long-term operation, in the surface and subsurface layers of the materials of parts in the tribo-joint, changes in the micromechanisms of fracture occur, which change the morphology of WPs. It has been shown that the developed computer program (CP) can be used to monitor the fractography of the surface of wear particles, and, accordingly, it is possible to control changes in the surface morphology. Therefore, it is possible to predict the operational stability and durability of the tribo-joint. A conceptual scheme for determining the performance of a tribotechnical assembly depending on the determined parameters of WPs is presented. The modes marked on it, including normal operation, transient, run-in, and catastrophic failure, can be evaluated by robotics approaches.

Contrasting two major Arctic coastal polynyas: the role of sea ice in driving diel vertical migrations of zooplankton in the Laptev and Beaufort seas

Abstract. The diel vertical migration (DVM) of zooplankton is one of the largest species migrations to occur globally and is a key driver of regional ecosystems and the marine carbon pump. Previously thought to be hampered by the extreme light regime prevailing in the Arctic Ocean, observations have revealed that DVM does occur in ice-covered Arctic waters and suggest the decline in Arctic sea ice may thereby impact DVM and its role in the Arctic ecosystem. However, coastal polynyas present a unique environment where open water or thin, nearly translucent, ice prevail when offshore winds advect the ice pack away from the coast, allowing light into the surface waters and potentially disrupting DVM. Here, four yearlong time series of acoustic backscatter collected by moored acoustic Doppler current profilers at two opposite sides of the circumpolar polynya system at the Laptev Sea shelf (2007–2008) and the Beaufort Sea shelf (2005–2006) were used to examine the annual cycle of acoustic scattering and therefore the annual cycle of DVM in these areas. The acoustic time series were used along with atmospheric and oceanic reanalysis and satellite data to interpret the results. Our observations show that DVM started to occur once the ice-free surface or under-ice layer irradiance exceeds a certain threshold (from ∼0.3 to 3.3 lx), which is about 2 to 10 times lower in the Beaufort Sea compared to the Laptev Sea. In the Laptev Sea, based on our data and methodology, DVM could not be detected during polar night. In contrast, civil twilight in the Beaufort Sea is sufficient to trigger DVM through polar night. This difference in DVM between the Laptev and Beaufort seas is not entirely assigned to the 3° difference in latitude between the mooring positions as it is also due to the different light threshold required to trigger DVM, different zooplankton communities' composition, and potentially different depths and predation pressures. We find examples in both the Laptev and Beaufort seas where the formation of polynyas and large leads caused DVM to abruptly cease or be disrupted, which we attribute to predator avoidance by the zooplankton in response to higher polar cod (Boreogadus saida) abundance near the open water. Finally, light attenuation by sea ice in the Beaufort Sea caused DVM to extend onto the polar day until the summer solstice. Overall, our results highlight the role of sea ice in disrupting synchronized DVM, the spatial variability in the relationship between sea ice and DVM, and the potential ecological impact of significant trends toward a more extensive circumpolar Arctic coastal polynya as part of changing ice conditions in the Arctic Ocean.

Methane and sulfide sulfur in water and bottom sediments of streams of the steppe zone of the European part of Russia

The results of long-term studies of the conjugate distribution of concentrations of methane (CH 4 ) and sulfide sulfur (S sulfide ) in bottom sediments of streams of the steppe zone of the European part of Russia are analyzed. In addition to CH 4 and S sulfide , Eh and pH values, humidity and density were determined in various sediment horizons; CH 4 , dry residue and pH values were determined in water. Concentrations of CH 4 in the water of watercourses vary from 0.1 to 2007.0 µl/l (median 24.3 µl/l), with the largest number of values (72 %) in the range 10.1–100.0 µl/l. The concentrations of CH 4 and Ssulfide in the bottom sediments of watercourses are quite high and vary, respectively, from 0.01 to 51.0 µg/g of wet sediment (median 1.35 µg/g) and from 0.001 to 4.50 mg/g of wet sediment (median 0.813 mg/g). Usually, there is an increase in CH 4 and S sulfide from the surface layer to the subsurface horizons, after which their concentrations decrease. The difference between the distribution of sulfides and the distribution of CH 4 is the more frequent occurrence of maximum concentrations of sulfides in less deep sediment horizons. Seasonal changes in the distribution of CH 4 and S sulfide along the vertical of sediments were recorded not only in terms of their concentrations, but also in the location of maximum and minimum values. There is a weak direct relationship between the concentrations of CH 4 and S sulfide , which indicates synchronous processes of formation of these gases in separate layers of sediments of the studied watercourses. The direct relationship established between the concentrations of CH 4 in water and the 0–2 cm layer of bottom sediments indicates sediments as an important source of CH 4 entering water and its emission into the atmosphere.

Deciphering Surface-Localized Structure of Nanodiamonds.

Nanomaterials, heralded as the "new materials of the 21st century" for their remarkable physical and chemical properties and broad application potential, have attracted substantial attention in recent years. Among these materials, which challenge traditional physical boundaries, nanodiamonds (NDs) are widely applied across diverse industries due to their exceptional surface multifunctionality and chemical stability. Nevertheless, atomic-level manipulation of NDs presents considerable challenges, which require detailed structural analysis to thoroughly elucidate their properties. This study utilizes density functional theory (DFT), lattice dynamics, and molecular dynamics (MD) simulations to analyze the structural and property characteristics of NDs. Fine structural analysis reveals that, despite variations in particle size, surface layer thickness remains relatively constant at approximately 3 Å. DFT methods enable computation of the surface layer to capture subtle electronic characteristics, while the internal core is analyzed via MD. Further investigation into amorphous structure control indicates that ND surface amorphous structures with a packing coefficient above 0.38 are thermodynamically stable. This study offers a novel approach to nanomaterial control in practical applications by elucidating the core-shell interactions and surface structures of NDs.

Variations in the slope of the earthquakes recurrence curve in the tonga subduction zone in 2005–2022

The Tonga‒Kermadec subduction zone is located between the Pacific and Australian plates and is the site of the highest rates of Pacific plate subduction and dominant extension. In 2006 and 2009 in this region, two strong earthquakes occurred with magnitudes Mw = 8.0 and 8.1. There are about 170 islands in the Tonga region. They are volcanic centers that have erupted regularly over the past few decades. The paper presents the results of determining temporal variations in the slope of the earthquakes recurrence curve (b-value) in the Tonga subduction zone for 2005–2022 and variations in b depending on depth. Temporal variations in the b-value reflect the general tendency for the most powerful earthquakes to occur against the background of a decrease in b-value only in the surface layer at depths of 0–100 km. By comparing the variation of b-value with depth with a tectonic model of the Tonga subduction zone, it suggested that lower b-value might reflect greater stress at the top of the subducted slab due to its bending. Elevated b-value can apparently be associated with stretching mechanisms. For the Tonga subduction zone, as for other subduction zones, the increased b-value identified at a depth of 90‒100 km, which may be due to the presence at this depth of a magmatic front, which is associated with active volcanism.

A Highly Active Molybdenum Carbide Catalyst with Dynamic Carbon Flux for Reverse Water‐Gas Shift Reaction

AbstractMolybdenum carbide has been reported as an efficient and stable catalyst for reverse water‐gas shift (RWGS) reaction. The conventional understanding of the mechanism suggests domination of the surface phenomena, with only surface or subsurface layers partaking in the catalytic cycle. In this study, we presented a highly active MoC catalyst from carburization process, which showed a mass‐specific reaction rate over 260 μm with dynamic carbon flux in the bulk phase of the catalyst. Through Isotopic Temperature‐Programmed Reaction (ITPR) analysis and Environmental Transmission Electron Microscopy (ETEM), we discerned dynamic carbon flow circulating between the α‐MoC bulk phase and the gas phase reactants under the RWGS reaction atmosphere. This circulation, essential to maintaining the structural stability of the metastable α‐MoC and its ultra‐high reactivity, is accompanied by thorough carbon component exchange among the bulk, the surface and the gas‐phase reactants during the reaction process.

A Highly Active Molybdenum Carbide Catalyst with Dynamic Carbon Flux for Reverse Water-Gas Shift Reaction.

Molybdenum carbide has been reported as an efficient and stable catalyst for reverse water-gas shift (RWGS) reaction. The conventional understanding of the mechanism suggests domination of the surface phenomena, with only surface or subsurface layers partaking in the catalytic cycle. In this study, we presented a highly active MoC catalyst from carburization process, which showed a mass-specific reaction rate over 260 μm with dynamic carbon flux in the bulk phase of the catalyst. Through Isotopic Temperature-Programmed Reaction (ITPR) analysis and Environmental Transmission Electron Microscopy (ETEM), we discerned dynamic carbon flow circulating between the α-MoC bulk phase and the gas phase reactants under the RWGS reaction atmosphere. This circulation, essential to maintaining the structural stability of the metastable α-MoC and its ultra-high reactivity, is accompanied by thorough carbon component exchange among the bulk, the surface and the gas-phase reactants during the reaction process.

Stimuli‐Responsive Smart Glass with Switchable Unidirectional Light Source for Enhanced Privacy/Indoor Illumination

AbstractLight manipulation is in high demand in science and industry. Smart glasses enable dynamic light control for indoor illumination, privacy protection, automobiles, and displays. However, existing technologies often limit single‐functionality (simultaneous bidirectional transparency or opacity) and strongly inherent user preferences. Here, a novel class of stimuli‐responsive smart glass featuring a switchable unidirectional light source using 2,2‐dimethoxy‐2‐phenylacetophenone (DMPAP)‐doped twisted hybrid polymer network liquid crystals (TH‐PNLCs) with a linear polarizer is developed. These DMPAP‐doped TH‐PNLCs exhibit a blue‐shift in spectra under cross‐polarizer, enhanced twist angle, and increased light amplitude compared with undoped devices. When subjected to external electric stimuli and edge light, the device emits light bi‐directionally with different polarizations. As a proof of concept, placing a transmissive polarizer in front of the homogeneous alignment layer (Surface A) enables light absorption and scattering toward vertical alignment (Surface B), ensuring privacy by blocking visibility from Surface A while keeping Surface B visible. Replacing the transmissive linear polarizer with a reflective one enhances light scattering, boosting intensity from Surface B, making the device ideal for energy‐efficient indoor lighting. Featuring fast switching times and robust endurance, this stimuli‐responsive smart glass offers a pioneering solution for green buildings and automobiles with enhanced privacy and indoor illumination.

Coconut residues increase light fraction of organic matter and water retention in semi-arid sandy soil under irrigated cultivation

ABSTRACT Coconut palm cultivation is associated with the generation of a large amount of residues, mainly from coconut shells, and their utilization in agriculture can represent an opportunity in the context of circular economy and climate change. This study aimed to determine the effect of coconut shell deposition on carbon (C) stocks, organic matter quality, and soil water retention in coconut palm cultivation in the Brazilian semi-arid region. The study was conducted in a commercial coconut palm cultivation area in Petrolina, Pernambuco State, Brazil, forming a chronosequence with 0, 2, 4, 5 and 6 years of coconut shells or coconut leaves application on soil surface. Carbon contents and stocks up to 0.40 m deep, the physical quality of soil organic matter, and soil water retention were evaluated. Coconut leaves and coconut shells increased organic C content in the surface layers of the soil, but the addition of residues did not influence soil C stocks. The light fraction of organic matter (>53 µm) was more sensitive to the management studied, while the heavy fraction of organic matter (<53 µm) was not significantly changed by the evaluated treatments. Coconut shells deposition on the surface increased the available water content to 8.5 % in the soil up to 0.40 m deep, but the effects were more significant on the surface. The highest C contents in the fraction >53 µm and the highest soil water retention were observed three years after the deposition of coconut shells on the surface, which suggests the need for reapplying the residues after this period to maintain the benefits.

Improving the Wear and Corrosion Resistance of Titanium Alloy Parts via the Deposition of DLC Coatings

This article compares the properties of the diamond-like carbon (DLC) coating with those of ZrN and (Zr,Hf)N coatings deposited on the Ti-6Al-4V titanium alloy substrate. To improve substrate adhesion during the deposition of the DLC coating, preliminary etching with chromium ions was conducted, ensuring the formation of a chromium-saturated diffusion surface layer in the substrate. A Si-DLC layer followed by a pure DLC layer was then deposited. The hardness of the coatings, their surface morphology, fracture strength in the scratch test, and tribological properties and wear resistance in the pin-on-disk test in contact with Al2O3 and steel indenters were investigated. The structure of the DLC coating was studied using transmission electron microscopy, and its corrosion resistance in an environment simulating blood plasma was also investigated. In the pin-on-disk test in contact with Al2O3 and AISI 52100 indenters, the DLC-coated sample demonstrates a much lower friction coefficient and significantly better wear resistance compared to the nitride-coated and uncoated samples. Both nitride coatings—(Zr,Hf)N and ZrN—and the DLC coating slow down the corrosive dissolution of the base compared to the uncoated sample. The corrosion currents of the (Zr,Hf)N-coated samples are 37.01 nA/cm2, 20% higher than those of the ZrN-coated samples. The application of (Zr,Hf)N, ZrN, and DLC coatings on the Ti-6Al-4V alloy significantly inhibits dissolution currents (by 30–40%) and increases polarization resistance 1.5–2.0-fold compared to the uncoated alloy in 0.9% NaCl at 40 °C. Thus, the DLC coating of the described structure simultaneously provides effective wear and corrosion resistance in an environment simulating blood plasma. This coating can be considered in the manufacture of medical products (in particular, implants) from titanium alloys, including those functioning in the human body and subject to mechanical wear (e.g., knee joint endoprostheses).

Fluoride Dose-Response and Anticaries Effect of Herbal Antibacterial Agents and (Nano-)Hydroxyapatite on Dentin Caries: An In Vitro Study.

The aim of the study was to investigate the caries-preventive effect of fluoride-free toothpastes, containing either herbal agents or (nano-)hydroxyapatite. Bovine dentin specimens each having a sound [ST], and a demineralized area [DT]) were prepared and randomly allocated to eleven groups (n=187). Treatments during pH-cycling (28 days;6x120min demineralization/day) were brushing 2x/day with: 0ppm F- [NaF0], 500ppm F- [NaF500], 1,100ppm F- [NaF1100], grape seed extract [GSE], (nano-)hydroxyapatite [nHA, HA], melaleuca oil [MO1, MO2, MO-CU] and propolis + myrrh [PM1, PM2] containing dentifrices. Dentifrice slurries were prepared with deionized water (1:3w/w). Differences in integrated mineral loss (∆∆Z) and lesion depth (∆LD) were evaluated before and after pH-cycling using transversal microradiography (TMR). The correlation between ΔΔZ/ΔLD and F- concentration (NaF0, NaF500, NaF1100) was strong for the DT (rΔΔZ,DT=0.681; p<0.001) and very strong for ST (rΔΔZ,ST=0.861; p<0.001); indicating a fluoride dose-response for both baseline substrate conditions. For ΔΔZDT and ΔLDDT only NaF1100 and GSE revealed significant differences compared with NaF0 (p<0.001, ANOVA). For ΔΔZST and ΔLDST significant differences could be found for NaF1100 and NaF500 compared to all fluoride-free groups (p≤0.002;ANOVA), without significant difference between fluoride-free groups (p=1.000;ANOVA). For DT and ST a hypermineralized surface layer and no surface loss could only be observed when fluoride was present. A dose-response for fluoride concentrations was observed in this mild demineralization pH-cycling model. Fluoride-free dentifrices containing grape seed extract or melaleuca oil showed certain preventive effect against further progression of root caries lesions. However, surface loss was observed for all fluoride-free dentifrices.

Exploring the promoting effect of lanthanum passivation on the photovoltaic performance of CZTSSe solar cells.

The significant open-circuit voltage (VOC) deficit poses a major obstacle to enhancing the efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. Interface passivation emerges as a potent strategy to regulate carrier transport and boost performance. Here, we innovatively introduced rare-earth lanthanum (La) to passivate the absorber interface by directly treating the absorption layer surface with an aqueous La3+ ion solution. This approach effectively minimizes interface defect concentrations and mitigates Fermi-level pinning effects. Notably, the VOC markedly increases from 406 to 456 mV after La treatment. Consequently, the power conversion efficiency soars from 6.78% (VOC = 406 mV, JSC = 29.95 mA/cm2, FF = 55.28%) for the reference cell to 7.89% (VOC = 451 mV, JSC = 30.12 mA/cm2, FF = 59.56%) for the optimized La-processed cell. This groundbreaking work opens up a novel avenue for advancing CZTSSe solar cell performance, offering promising implications for the future of CZTSSe thin-film photovoltaic technology.

Contrasting Southern Ocean Sea Level Responses to Surface Flux Changes in Eddy-Rich and Eddy-Parameterized Climate Model Configurations

Abstract The impact of ocean model resolution on sea level projections in the Southern Ocean is investigated using eddy-rich (ER) and eddy-parameterized configurations of the Max Planck Institute Earth System Model under the Shared Socioeconomic Pathway (SSP) 5-8.5 scenario. We employ the Flux-Anomaly Forced Model Intercomparison Project (FAFMIP) experiment—heat, stress, and freshwater perturbations—at both resolutions to pinpoint the sources of these differences. South of 55°S, we found that the changes in thermosteric and halosteric sea levels vary substantially between resolutions due to different responses to freshwater perturbations. In the eddy-parameterized model, the resulting increase in stratification suppresses the mixing of salt and heat from the Circumpolar Deep Water with surface layers. These cause differences in the response of surface fluxes and meridional transports yielding an increase in thermosteric sea levels and a decrease in halosteric sea levels. In the eddy-rich configuration, the main driver of eddy-induced warming and salinification between 40° and 44°S is wind stress perturbations. The efficiency of direct eddy effects in ER is restricted to small areas such as the Agulhas Retroflection, the Brazil–Malvinas confluence zone, the Tasman Sea, and, to some extent, the Antarctic Circumpolar Current (ACC). Contrary to expectations, ACC transport increases in the eddy-rich model while decreasing in the eddy-parameterized model under the SSP5-8.5 scenario. FAFMIP results reveal that this decrease is a result of the overcompensation of wind-induced changes by freshwater flux forcing. These results underscore the critical importance of high-resolution models for capturing the processes in sea level projections in the Southern Ocean and beyond. Significance Statement We studied how ocean model resolution affects sea level projections in the Southern Ocean using Max Planck Institute Earth System Model simulations. Higher-resolution models provide a more accurate representation of ocean circulation and its response to changing forcings. We examined how surface heat, momentum, and water fluxes, both separately and combined, shape ocean dynamics. In a strong global warming scenario, significant differences in steric sea level change were observed south of 55°S between the model that simulates eddies and the one that has their effects parameterized. The response to surface freshwater forcing is the primary cause of these differences. Our findings emphasize the critical role of ocean model resolution in accurately understanding and predicting future sea level changes, which is essential for effectively addressing our needs for adaptation.

Assessment of the Effect of Multiple Processing of PHBV-Ground Buckwheat Hull Biocomposite on Its Functional and Mechanical Properties.

The influence of the addition of ground buckwheat hulls on the properties of biocomposite on the basis of 3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) is presented here. The changes in the material after repeated reprocessing-up to five recycling cycles-are written in the paper. Analysis of the shrinkage, water adsorption, selected mechanical properties, tensile impact strength, hardness and the microstructure of the surface layer was performed. The results show that the application of the buckwheat hulls into the biopolymer decreases the material shrinkage. It improves the material dimensional stability, as well as increases the water adsorption in the wake of the hydrophobic properties of the filler. The addition of the natural filler also leads to an increase in composite stiffness. The decrease in the tensile impact strength and the elongation at break is also noted. The reprocessing of the biocomposite initially led to a decrease in its mechanical properties, but the results stabilized after further processing cycles. This indicates the improvement of the microstructure homogeneity. The microscopic analysis shows that buckwheat hull particles were better embedded in the matrix after recycling. The increase in hardness was also noted. The PHBV-ground buckwheat hull biocomposite is characterized by stable mechanical properties and by recycling resistance, which makes it a promising material in terms of the sustainable development.