Potential Curves Research Articles

Experimental and Numerical Investigation of One-Dimensional Electroosmotic Consolidation Based on Segment Inheritance Strategy

The attenuation of effective potential is a significant factor leading to the low postdrainage efficiency in the electroosmotic consolidation and drainage methods. In this study, the influence of the attenuation of effective potential on the electroosmotic consolidation process and the problem of solving the governing equations were investigated. A 102.5-hr one-dimensional electroosmotic consolidation test was performed to monitor the changes in the properties of the soil interior and the soil–electrode interface, and the variation curve of the effective potential in the test model was measured. The time-dependent nature of the potential distribution due to the attenuation of effective potential contradicts the assumption of introducing intermediate variables. To address this key issue, the variation curve of the effective potential was linearly segmented, ensuring the validity of introducing intermediate variables within each local state segment. Based on the continuity between state segments, the initial conditions of the governing equations in different state segments were updated, thereby extending the differential iteration within local state segments to the entire electroosmotic time domain. A finite-difference program for this method was developed using the Python language. Calculations and analyses based on the measured potential data were performed, revealing that a decrease in potential leads to a reduction in the effectiveness of electroosmotic drainage and consolidation in terms of the instantaneous distribution of pore pressure and the overall average degree of consolidation. This method can reflect the influence of the attenuation of effective potential on the pore water pressure during the electroosmotic consolidation process. The research findings of this paper can provide theoretical and numerical support for the improvement and engineering application of the electroosmotic consolidation and drainage method.

Chemically Accurate Potential Curves for H2 Molecules Using Explicitly Correlated Qubit-ADAPT.

With the recent advances in the development of devices capable of performing quantum computations, a growing interest in finding near-term applications has emerged in many areas of science. In the era of nonfault tolerant quantum devices, algorithms that only require comparably short circuits accompanied by high repetition rates are considered to be a promising approach for assisting classical machines with finding a solution on computationally hard problems. The ADAPT approach previously introduced in Nat. Commun. 10, 3007 (2019) extends the class of variational quantum eigensolver algorithms with dynamically growing ansätze in order to find approximations to the ground and excited state energies of molecules. In this work, the ADAPT algorithm has been combined with a first-quantized formulation for the hydrogen molecule in the Born-Oppenheimer approximation, employing the explicitly correlated basis functions introduced in J. Chem. Phys. 43, 2429 (1965). By the virtue of their explicit electronic correlation properties, it is shown in classically performed simulations that chemical accuracy (<1.6 mHa) can be reached for ground and excited state potential curves using reasonably short circuits.

Electrokinetic study of pyrochlore in the presence of calcium and magnesium electrolytes in the context of water reuse

This paper aims to present an adequate methodology for pyrochlore from flotation process sample to be used in fundamentals surface properties studies based on zeta potential measurements under Ca and Mg electrolytes in chlorides and sulfate media. A niobium ore concentrate with small amount of fine particles (−38 µm < 2.5%), composed by 61.8% (Nb2O5), 16.5% (CaO), 7.19% (TiO2), and 6.30% (Na2O), being pyrochlore (92.8%) the Nb-bearing mineral was used. The association of acid leaching (HCl 0.1 mol/L, 70 °C, 120 min, 20 g/L and 300 rpm) and heat treatment (300 °C, 120 min and 5 g/crucible) reduced the sample's flotability by 94% which was suitable for fundamental studies. Ca and Mg ions modified the zeta potential curve of the pyrochlore without causing any changes in the pHPIE, which occurs at pH 3.1. Ca(OH)2 precipitation was not evidenced in the system containing calcium ions. Thermodynamic simulation predicted its precipitation above pH 12.3 which is outside of the range of pH studied (2.0 to 12.0). However, Mg(OH)2 precipitation associated to the formation of metal hydroxy complexes predicted by PHREEQC (version 3.7.3, llnl.dat database) contributed to the reversal in the zeta potential of the sample. The anion supporting the metallic cations also contributed to the zeta potential alteration mainly due to the ionic strength modification associated to sulfate and chloride anion charges. The alternation of chloride and sulfate sources for [Ca + Mg] system did not affect the zeta potential curves.

Promising Eco-friendly Inhibitor Potency: Elaeagnus Angustifolia Leaf Extract for Mild Steel

In this research, the potential of Elaeagnus angustifolia tree leaf extract as a green corrosion inhibitor for mild steel in hydrochloric acid solution was examined. The stock concentration of the aqueous extract was determined to be 0.38% (w/v). Other experimental solutions were created by diluting four different extract concentrations in aggressive solution. Experimental measurements, including linear polarization (LPR), electrochemical impedance spectroscopy (EIS), and semi-logarithmic current potential curves by Tafel extrapolation method, were employed to validate the corrosion inhibition effects of the plant leaf extract at varying concentrations. Notably, oleaster leaf extract demonstrated a corrosion protection of over 80% for mild steel, even at low concentrations, attributed to its abundance in secondary metabolites such as polyphenols and flavonoids. The atomic force microscopy (AFM) surface maps provide robust evidence for the electrochemical measurement data.

Toward a quasi-satisficing sustainable manufacturing

Sustainable development should meet the needs of the present without compromising future generation needs. While political and standards approaches insist on regulatory directives, this paper proposes a quasi-satisficing methodology considering the sustainability topic within a larger encompassing framework. Starting from three reflections originated by the classical thermodynamics, the effect of knowledge accumulation on the Production Possibility Frontier (PPF), and a model for the human wellbeing in manufacturing ecosystem, this paper proposes a new production model and a heuristic approach to drive the decision process towards sustainable manufacturing.

Nano-topography and functionalization with the synthetic peptoid GN2-Npm9 as a strategy for antibacterial and biocompatible titanium implants

In recent years, antimicrobial peptides (AMPs) have attracted great interest in scientific research, especially for biomedical applications such as drug delivery and orthopedic applications. Since they are readily degradable in the physiological environment, scientific research has recently been trying to make AMPs more stable. Peptoids are synthetic N-substituted glycine oligomers that mimic the structure of peptides. They have a structure that does not allow proteolytic degradation, which makes them more stable while maintaining microbial activity. This structure also brings many advantages to the molecule, such as greater diversity and specificity, making it more suitable for biological applications. For the first time, a synthesized peptoid (GN2-Npm9) was used to functionalize a nanometric chemically pre-treated (CT) titanium surface for bone-contact implant applications. A preliminary characterization of the functionalized surfaces was performed using the contact angle measurements and zeta potential titration curves. These preliminary analyses confirmed the presence of the peptoid and its adsorption on CT. The functionalized surface had a hydrophilic behaviour (contact angle = 30°) but the hydrophobic tryptophan-like residues were also exposed. An electrostatic interaction between the lysine residue of GN2-Npm9 and the surface allowed a chemisorption mechanism. The biological characterization of the CT_GN2-Nmp9 surfaces demonstrated the ability to prevent surface colonization and biofilm formation by the pathogens Escherichia coli and Staphylococcus epidermidis thus showing a broad-range activity. The cytocompatibility was confirmed by human mesenchymal stem cells. Finally, a bacteria-cells co-culture model was applied to demonstrate the selective bioactivity of the CT_GN2-Nmp9 surface that was able to preserve colonizing cells adhered to the device surface from bacterial infection.

Mechanism of long-range hydrophobic force based on cavitation of metastable liquid film

Hydrophobic force, a key driving force in colloid physicochemical system and biological macromolecular system, exhibits a distinct multi-scale effect. The prevailing scholarly consensus attributes long-range hydrophobic force to bubble bridging, facilitated by unstable liquid film cavitation, while short-range force is thought to arise from the reorganization of water molecules at the solid-liquid interface. However, a comprehensive theoretical study remains elusive. To further elucidate the mechanism of the long-range hydrophobic force based on unstable liquid film cavitation, we carry out systematic research on the long-range hydrophobic force between perfluorooctyl trichlorosilane hydrophobic particles and the surface, by utilizing atomic force microscopy (AFM) and molecular dynamics simulations. According to AFM force tests, the long-range hydrophobic force escalates incrementally with subsequent close contacts before reaching a plateau. On the tenth contact, the penetration curve exhibits a sudden jump to an adhesion distance of 502.01 nm. A distinct step in the retraction curve suggests the rupture of the cavitation bubble capillary bridge. Importantly, the classical capillary force mathematical model provides an effective fit for the penetration curve. Our calculations estimate the volume of the capillary bridge at 0.30 μm³, offering direct theoretical evidence of the unstable liquid film cavitation bubble capillary bridge. Further insights are gained from large-scale tensile molecular dynamics simulations by using GROningen MAchine for Chemical Simulations (GROMACS). The inherent correlation mechanism of the formation, evolution, and mechanical behavior of the cavitation bubble capillary bridge in the separation process of hydrophobic particles are further explored from a molecular perspective. The results demonstrate that the local pressure drop occurring at the moment of “jump-out” separation of the hydrophobic particles attracts nitrogen molecules to diffuse into the liquid film, thereby forming a cavitation bubble capillary bridge. Simultaneously, a jumping behavior is observed in the calculated spring potential curve at the moment of capillary bridge rupture. Finally, the influence of solution gas content on long-range hydrophobic force is investigated. There is a positive correlation between gas molecule content and both the growth rate of cavitation bubble capillary bridge volume and the length of capillary bridge stretch-rupture, further demonstrating the gas concentration dependence of long-range hydrophobic forces. In a word, revealing the long-range hydrophobic force mechanism based on the cavitation of unstable liquid film can enhance our understanding of the interaction between colloid physical chemistry and biological macromolecules. Meanwhile, hydrophobic force is the fundamental driving force of particle-bubble adhesion in mineral flotation system, and the revelation of its action mechanism has important guiding significance for regulating the actual mineral flotation process.

Raman spectroscopic study of centered OHO hydrogen bonding in the hydrogen maleate anion

The work presents Raman spectra of potassium salts of the protonated K[C4H3O4] and deuterated K[C4H2DO4] maleate anion in the temperature range 5 K – 300 K. It is shown that at low (5 K) temperature roughly half of the protonated and one third of the deuterated H-bonds in maleate anions is extremely strong, the potential curve of the proton (deuteron) is single-well, in which the particles are located at the bond center, and the symmetry of the anions is C2v. As the temperature increases, the deuterons begin to shift toward one of the oxygen atoms at T &gt; 30 K, and the proton at T &gt; 100 K. At room temperature, the symmetry of both compounds becomes C1h.

Identifying Separation Potency and Relationship of Grade and Density of Copper Ore for Gravity-Based Early Coarse Gangue Rejection using Statistical Method

The mineral processing industry faces a pressing challenge of declining productivity, particularly in metal minerals production, driven by soaring operational costs, with crushing and grinding operations accounting for a substantial portion of the energy consumption. To mitigate these challenges, early gangue rejection or preconcentration is proposed as an effective solution. This approach involves the removal of non-valuable materials and the concentration of valuable minerals at the initial processing stages, leading to increased efficiency, higher ore feed grades, cost savings, and reduced environmental impact. Various methods for gangue rejection exist, with gravity-based separation and ore sorting being the predominant options. Gravity-based separation stands out for its simplicity and versatility, making it the preferred choice in many scenarios. This study introduces a novel approach for evaluating gangue rejection potential, optimizing data distribution, and generating theoretical separation potential curves that account for both grade and density criteria. These curves provide insights into material rejection, metal losses, and optimal separation points, offering valuable guidance for mineral processing operations. Additionally, the study investigates the correlation between raw ore grade and density data, highlighting a strong relationship across different size fractions. This finding suggests that gravity-based separation can effectively rely on both grade and density parameters, resolving previous disparities observed in distribution models. By shedding light on advanced gangue rejection strategies, this research contributes to improved productivity and informed decision-making in the mineral processing industry.

The geometry of the Rindler black hole

Using Einstein's equations for gravity for a spherically symmetric field in a static state and the mass function method, a general form of the metric for Schwarzschild-type black holes is proposed. A qualitative analysis of Schwarzschild, Reissner–Nordström and Rindler geometries is performed. In the paper, it is found that Rindler black hole geometry is structurally inverse to Reissner–Nordström geometry, i.e. it has two T-regions and one R-region. In this regard Rindler geometry is like geometry of the Kottler black hole, which does not have flat asymptotics. Potential curves in the gravitational field of the Rindler black hole are constructed, which makes it possible to calculate the limits of finite motion for a test particle in this field. In addition, a qualitative comparison with the known Schwarzschild field metric is performed. Their similarity in behavior at small distances and absolutely different behavior at large scales are shown. Using the known accelerations of the Pioneer spacecraft, limits are numerically found for the T- and R-regions of their motion in the gravitational field of the Solar System.

Study on Quench Sensitivity during Isothermal Treatment of 7A65 Aluminum Alloy.

The quenching sensitivity of 7A65 aluminum alloy was investigated using interrupted quenching experiments. The time-temperature transformation (TTT) and time-temperature performance (TTP) curves of the alloy were determined. The results indicate that the nose temperature is about 320 °C and the quenching sensitivity temperature range is from 240 °C to 360 °C. During the isothermal treatment, the supersaturated solid solution resolves to the equilibrium phase of η (MgZn2), and the precipitation rate is the largest at about 320 °C. Through transmission electron microscope (TEM) observation and X-ray diffraction (XRD) tests, it was found that with the extension of the isothermal holding time, the originally dispersed η' phase gradually decreases until disappear, and the number of η phase increases and gradually grows up at the grain boundary or around the Al3Zr particles. The rod-like η phase at the grain boundary is distributed from discontinuous distribution to chain-like continuous distribution, and the precipitation free zone (PFZ) is gradually generated and widened as the holding time is extended. At the nose temperature, the driving force of nucleation is high, and the diffusion rate is fast, which promotes the precipitation and growth of η phases. The coarse η phase weakens the mechanical properties. According to the results, it is recommended to increase the cooling rate at the sensitivity temperature range to reduce the precipitation of the η phase and decrease the quenching cooling rate from solution temperature to 360 °C to reduce residual stresses in the components.

EXPLORING EFFICIENCY GROWTH OF ADVANCED TECHNOLOGY-GENERATING SECTORS IN THE EUROPEAN UNION: A STOCHASTIC FRONTIER ANALYSIS

This study investigates the efficiency growth of advanced technology-generating sectors within the European Union (EU). Using a stochastic frontier analysis of annual sector-level panel data from 2000 to 2019, we examine sectoral (NACE two-digit level) and territorial implications. Our findings indicate that technological change was more intense in advanced technology-generating sectors than in other economic sectors, primarily driven by fixed capital investments. However, the impact of in-house research and development varied. Economic sectors such as pharmaceuticals and motor vehicles struggled to improve their production efficiency due to high competition and market specificity. A comparative analysis of EU economies showed a lower level of production efficiency in catching-up economies. Nevertheless, these economies contributed to the shift of the production possibility frontier in certain sectors on the EU level. Therefore, this study contributes to the ongoing scientific discussion on technological innovations in diverse territories, suggesting that less-developed economies could generate technological advancements in specific areas. We also discuss the implications for innovation and industrial policy actions.

Enhanced corrosion resistance of epoxy resin coating via addition of CeO2 and benzotriazole

The use of fillers to enhance the corrosion protection of epoxy resins has been widely applied. In this work, CeO2 and Benzotriazole (BTA) were introduced into an epoxy resin to enhance the corrosion resistance of Q235 carbon steel. SEM results indicated that the CeO2 grains were rod-like and ellipsoidal in shape, and the distribution pattern of BTA was analyzed by EDS. The dynamic potential polarization curve proved the excellent corrosion resistance of the composite epoxy resin with CeO2 and BTA co-addition; and electrochemical impedance spectroscopy test (EIS) analysis indicated the significantly enhanced long-term corrosion protection performance of the composite coating. And the optimal protective performance was provided by the coating containing 0.3 wt.% CeO2 and 20 wt.% BTA, which attributed to the barrier performance of CeO2 particles and chemical barrier effect of BTA. The formation of corrosion products was analyzed using XRD. In addition, the corrosion resistance mechanism of the coating was also discussed in detail.

Influence of Moisture on the Electrochemical Performance of Prelithiated C/SiOx Composite Anodes for Li-Ion Batteries

Prelithiation of Si containing anodes has commonly been acknowledged as a potential solution to the challenge of the high irreversible lithium losses that still hinder the widespread adoption of this next-generation anode active material. However, upscaling and implementation in the process chain remain major hurdles for most proposed prelithiation processes. A significant part of this comes down to the high reactivity of prelithiation agents and prelithiated electrodes towards moisture. In industrial scale electrode production, dry rooms with dew point controlled atmospheres are already in use, but are a significant cost factor. Therefore, the compatibility of prelithiated electrodes with dry room conditions is a major factor for the implementation of prelithiation into existing production lines.In this work C/SiOx composite anodes are electrochemically prelithiated and subsequently subjected to industry relevant moisture levels. The influence of dew point and exposure time is examined. After exposure, the anodes are assembled into half-cells and their electrochemical performance during the first lithiation/delithiation cycle is analysed using a 3-electrode setup. The evaluation of the specific capacities and the potential curves provides information about the extent of the damage to the electrode. The results indicate a promising stability window for dew points of up to -40° C and realistic exposure times of up to one hour. Additional aging investigations in full cells against NMC622-based cathodes confirm these findings. Furthermore, electrochemical impedance spectroscopy, XPS and ToF-SIMS measurements are performed to elucidate the effect of moisture exposure on the solid electrolyte interface (SEI) composition. The results suggest the development of a double-layered SEI structure, where the first layer forms during prelithiation and is altered by moisture exposure, while the second layer forms on top of the first layer during formation. Figure 1

Electrode-Resolved Impedance and Potential Measurements to Investigate the Rate Capability of High Loading Micron-Silicon Anodes in All-Solid-State Batteries

In order to enable the market introduction of all-solid-state batteries (ASSBs), several anode concepts are under investigation to increase the energy density compared to graphite anodes, while maintaining long cycle-life. At the same time, the production costs must be the same or even reduced in comparison with classical lithium-ion batteries. Besides lithium metal as anode material, which still poses significant technical challenges, more and more interest is being directed toward materials that form lithium alloys. One of the most attractive candidates is silicon, which has a low delithiation potential of around 0.45 V vs. Li+/Li and an attractive theoretical gravimetric capacity of 3579 mAh/gSi, which in the fully lithiated state corresponds to a volumetric capacity of ≈2190 mAh/cm3, even higher than the one reachable by lithium metal.Silicon-containing anodes are already being introduced in classical lithium-ion batteries. For that system, the lithium-ion conduction across the anode electrode is mainly provided by the liquid electrolyte that fills the pores of the electrode, while the electrical conduction is enhanced by the addition of graphite and/or conductive carbon additives, because crystalline silicon is only a semiconductor. As is well known, the major issue with silicon anodes is the volume expansion of 300% upon lithiation of silicon, inducing severe cracking of µm-sized silicon particles as well as continuous solid electrolyte interphase (SEI) growth, both of which lead to a fast capacity fading.The intrinsic solid nature of all-solid-state batteries opens the possibility of a new electrode concept that has the potential to mitigate the above-mentioned drawbacks of silicon. Indeed, the silicon particles themselves could be used for the lithium-ion conduction across the electrode, so that anode electrodes can be prepared that are free of electrolyte, thereby largely restricting SEI formation to the anode/separator interface .In this work, anodes with >90% weight of silicon are prepared by coating a water-based slurry that contains microscale silicon particles (ca. 2-4 µm diameter) as active material, the rest being made up of LiPAA and NaCMC as binders as well as C65 carbon as conductive additive. The combination of the water-based process and the microscale dimension of the silicon particles make this electrode concept easily scalable and cost-effective.To reach a competitive areal silicon anode capacity of 3 mAh/cm2, with the full utilization of the silicon, only a thin layer is needed (pristine thickness of 8 µm when the anode porosity is 50%). The thickness variation and the anode morphology are being investigated by examining cross-sectional scanning electron microscopy (SEM) images at different states-of-charge (SOC). After the first complete lithiation, the anode consists of a fully dense and compact Li3.75Si alloy block of 15 µm thickness. Upon its complete delithiation, a peculiar porous columnar morphology is formed that on account of the void space between the columns and within the columns retains a thickness of 11 µm. This peculiar morphology was recently reported in the literature (Tan et al., Science 373 (2021), 1494–1499); and seems to be reversible during subsequent lithiation and delithiation processes. For example, our half-cells utilizing an InLi counter electrode and operating at 70 MPa have more than 80% capacity retention after 350 cycles at a rate of C/5, with an average coulombic efficiency higher than 99.9%. The reason for this promising stability could be attributed to the minimal loss of lithium into the SEI, which is limited to the geometrical contact area between the silicon and the solid electrolyte separator.To better understand the electrochemical and mechanical characteristics of these silicon anodes, they are investigated in full-cells, utilizing an NCM composite cathode, while the anode potential is monitored by using a gold wire micro reference electrode (µ-RE) which was recently developed in our group (Sedlmeier et al., J. Electrochem. Soc. 170 (2023) 030536). This specific µ-RE, which has a defined and stable potential, allows to precisely deconvolute the potential curves of cathode and anode, and also to measure and separate the impedance contributions of the two electrodes. Therefore, the impedance of the silicon anode is measured at different SOC to understand how the contact resistances, the charge-transfer resistance, and the solid-state diffusion affect its overall impedance. In particular, the low impedance at high SOC enables to reach a good fast charging rate capability up to 1C without lithium metal plating and dendrite formation, as reported in Figure 1. However, in order to explore whether the fast charging goal of 4C (80% of the capacity in 15 minutes) can be reached, the influence of the carbon additive, operating temperature and applied pressure are being investigated. Figure 1

Growth dynamics of untreated meningiomas.

Knowledge about meningioma growth characteristics is needed for developing biologically rational follow-up routines. In this study of untreated meningiomas followed with repeated magnetic resonance imaging (MRI) scans, we studied growth dynamics and explored potential factors associated with tumor growth. In a single-center cohort study, we included 235 adult patients with radiologically suspected intracranial meningioma and at least 3 MRI scans during follow-up. Tumors were segmented using an automatic algorithm from contrast-enhanced T1 series, and, if needed, manually corrected. Potential meningioma growth curves were statistically compared: linear, exponential, linear radial, or Gompertzian. Factors associated with growth were explored. In 235 patients, 1394 MRI scans were carried out in the median 5-year observational period. Of the models tested, a Gompertzian growth curve best described growth dynamics of meningiomas on group level. 59% of the tumors grew, 27% remained stable, and 14% shrunk. Only 13 patients (5%) underwent surgery during the observational period and were excluded after surgery. Tumor size at the time of diagnosis, multifocality, and length of follow-up were associated with tumor growth, whereas age, sex, presence of peritumoral edema, and hyperintense T2-signal were not significant factors. Untreated meningiomas follow a Gompertzian growth curve, indicating that increasing and potentially doubling subsequent follow-up intervals between MRIs seems biologically reasonable, instead of fixed time intervals. Tumor size at diagnosis is the strongest predictor of future growth, indicating a potential for longer follow-up intervals for smaller tumors. Although most untreated meningiomas grow, few require surgery.

Trade-Offs in Ecosystem Services: Clarifying Concepts and Measuring Severity within the Production Possibility Frontier Framework

Production possibility frontier (PPF) in economics denotes the set of all efficient combinations of the amounts of two or more goods that can be produced from the given resources and within the given technology. In the ecosystem services context, it corresponds to all efficient combinations of the amounts of two or more ecosystem services that can be obtained from the given land area within the given management framework. PPF thus captures the conflict, or trade-off, between the production of different goods or services. However, there is a lack of an agreed understanding of what precisely in a PPF expresses the degree of that conflict. This lack of clarity may greatly confound the discussions on trade-offs. This paper tries to answer the two following questions: (1) what exactly is trade-off in the PPF context? (2) how to effectively measure and compare trade-offs across PPFs? In response to the second question, a quantitative generic measure of trade-off severity is proposed.

Bound and autoionizing potential energy curves in the CH molecule

This article presents a method of computing bound state potential curves and autoionizing curves using fixed-nuclei R-matrix data extracted from the Quantemol-N software suite. It is a method based on two related multichannel quantum-defect theory approaches. One is applying bound-state boundary conditions to closed-channel asymptotic solution matrices, and the other is searching for resonance positions via eigenphase shift analysis. We apply the method to the CH molecule to produce dense potential-curve datasets presented as graphs and supplied as tables in the publication supplement.

The effect of acetic acid on the crevice corrosion of P110 steel in simulated oilfield produced water

P110 steel, widely utilized in oil and gas operations, is renowned for its robust mechanical properties, satisfactory corrosion resistance, and significant economic advantages. This study aims to investigate the influence of acetic acid on the crevice corrosion behavior of P110 steel in simulated oilfield produced water. A comprehensive range of techniques was employed for this analysis, including dynamic potential polarization curves, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy. The results highlight that the introduction of acetic acid significantly compromises the resistance of P110 steel to crevice corrosion. As the concentration of acetic acid increases, a corresponding escalation in corrosion products outside the crevice is observed, forming a protective layer on the surface of the P110 steel beyond the crevice. These insights provide a theoretical basis for enhancing the safety performance of oil well tubing, reducing operational hazards, and mitigating environmental impact.

Identifying critical landscape patterns for simultaneous provision of multiple ecosystem services – A case study in the central district of Wuhu City, China

Landscape patterns have a global impact on ecosystem services (ESs). Managing land to enhance the provision of multiple ESs is vital for ecological resilience and sustainable development. Identifying critical landscape patterns that simultaneously influence multiple ESs provision based on understanding ES trade-offs is needed. Our study aims to develop an approach to find the relationship between multiple ESs provision and landscape patterns, identify the critical landscape patterns that simultaneously promote multiple ESs provision, and give suggestions on land management based on an understanding of the relationships of ESs. Taking the central district of Wuhu City as an example, production possibility frontier (PPF) and Pareto ranks are used to identify relationships between ESs and extract the landscape pattern characteristics of samples that effectively enhance multiple ESs. Our analysis of trade-offs between ESs highlights the complexity of ES relationships and emphasizes the necessity for multi-dimensional investigative approaches. Landscape metrics of Mean Perimeter Area Ratio (PARA_MN), Coefficient of Variation of Perimeter (PERI_CV), Area-weighted Mean Fractal Dimension (FRAC_AM), and Relative Mutual Information (RELMUTINF) emerged as critical determinants of multiple ESs supply. Our findings suggest enhancing patch shape complexity when conducting land use planning to avoid homogenization and keeping differences between the diversity of land use categories and the diversity of adjacencies small. Also, we recommend caution in using high contagion as the only criterion for land use planning, as its effects may vary on different ES targets.