Search Results (745)

This study illustrates the complex interaction between environmental parameters and carbonate distribution in marine sediments along the Tarfaya–Boujdour coastline (26–28° N) of Northwest Africa. Analysis of 21 surface sediment samples and their associated bottom water properties (salinity, temperature, dissolved oxygen, nutrients) reveals CaCO₃ content ranging from 16.8 wt.% to 60.5 wt.%, with concentrations above 45 wt.% occurring in multiple stations, especially in nearshore deposits. Mineralogy indicates a general decrease in quartz, with an arithmetic mean and standard deviation of 52.5 wt.% ± 19.8 towards the open sea, and an increase in carbonate minerals (calcite ≤ 24%, aragonite ≤ 10%) with depth. Sediments are predominantly composed of fine sand (78–99%), poorly classified, with gravel content reaching 6.7% in energetic coastal stations. An inverse relationship between organic carbon (0.63–3.23 wt.%) and carbonates is observed in upwelling zones, correlated with nitrate concentrations exceeding 19 μmol/L. Hydrological gradients show temperatures from 12.41 °C (offshore) to 21.62 °C (inshore), salinity from 35.64 to 36.81 psu and dissolved oxygen from 2.06 to 4.21 mL/L. The weak correlation between carbonates and depth (r = 0.10) reflects the balance between three processes: biogenic production stimulated by upwelling, dilution by Saharan terrigenous inputs, and hydrodynamic sorting redistributing bioclasts. These results underline the need for models integrating hydrology, mineralogy and hydrodynamics to predict carbonate dynamics in desert margins under upwelling. Full article

A reconfigurable microwave absorber based on double-layer metasurface is proposed for wide microwave band applications spanning 3 to 14 GHz. The absorber consists of two layers with two-dimensional array of four-semi-circular and square-ring metasurface patches loaded impedance devices, two spacers composed of honeycomb materials, and a bottom copper substrate. In order to break through the limitation of single-layer absorbers at finite resonant frequencies, a special double-layered metasurface structure is adopted. The layer I of metasurface is designed with two resonant peaks near the X band and transmission performance in the C band. Simultaneously, the layer II of metasurface is designed with a resonant peak near the C band and reflection performance in the X band. To achieve a reconfigurable effect, impedance adjustable device, such as PIN diodes, are connected between patterned metasurface cells of layer I. The simulation results revealed that the double-layer metasurface absorber can not only achieve broadband absorption effect, with the reflection value below −10 dB from 3.1 to 14.2 GHz, but also adjust the electromagnetic absorption rate, with the reflection value below −20 dB covers a bandwidth of 6.6–9 GHz. The good agreement between simulation and measurement validates the proposed absorber. Full article

In this study, we investigated the influence of water invasion velocity on gas–water permeability in bottom-water gas reservoirs. We conducted simultaneous core water invasion experiments under actual reservoir conditions, systematically examining varied permeability cores and multiple influx velocities. Two data processing methods were comparatively validated, analyzing gas–water relative permeability curves, fractional flow curves, and injection volume–recovery efficiency relationships. The results indicate that under HTHP (high-temperature, high-pressure) conditions, gas relative permeability declines faster, while water relative permeability increases more significantly. NMR imaging revealed that water preferentially invades smaller pores, accelerating gas–water flow before entering larger pores, leading to a rapid increase in water relative permeability. Long-core experiments unveiled a waterfront “stepwise advance” and localized water channeling due to heterogeneity, which were not observed in short-core tests. Water influx velocity critically influences fractional flow curves: high velocities cause rapid post-breakthrough water cut increase, easily inducing fast water breakthrough and coning, whereas low velocities promote a uniform frontal advance. HTHP (high-temperature, high-pressure) long-core flooding experiments more accurately reflect actual reservoir water influx dynamics, offering key insights for optimizing development strategies, delaying water influx, and enhancing recovery efficiency. Full article

This study presents an analytical model to reduce the impact of wave-induced forces on a vertical seawall by introducing a floating elastic plate (EP) located at a specific distance from two bottom-standing porous structures (BSPs). The hydrodynamic interaction with the EP is described using thin plate theory, while the fluid flow through the porous medium is described by the model developed by Sollit and Cross. The resulting boundary value problem is addressed through linear potential theory combined with the eigenfunction expansion method (EEM), and model validation is achieved through consistency checks with recognized results from the literature. A comprehensive parametric analysis is performed to evaluate the influence of key system parameters such as the porosity and frictional coefficient of the BSPs, their height and width, the flexural rigidity of the EP, and the spacing between the EP and BSPs on vital hydrodynamic coefficients, including the wave force on the seawall, free surface elevation, wave reflection coefficient, and energy dissipation coefficient. The results indicate that higher frictional coefficients and higher BSP heights significantly enhance wave energy dissipation and reduce reflection, in accordance with the principle of energy conservation. Oscillatory trends observed with respect to wavenumbers in the reflection and dissipation coefficients highlight resonant interactions between the structures. Moreover, compared with a single BSP, the double BSP arrangement is more effective in minimizing the wave force on the seawall and free surface elevation in the region between the EP and the wall, even when the total volume of porous material remains unchanged. The inter-structural gap is found to play a crucial role in optimizing resonance conditions and supporting the formation of a tranquility zone. Overall, the proposed configuration demonstrates significant potential for coastal protection, offering a practical and effective solution for reducing wave loads on marine infrastructure. Full article

In late August and mid-November 2024, and late February and mid-May 2025, four surveys were conducted in the Kalasuke Reservoir section of the Irtysh River, resulting in the collection of 296 samples of P. fluviatilis. Sampling tools included drift gillnets with a mesh size of 5 cm and an outer mesh size of 10 cm, bottom cages with a mesh size of 1 cm, and fishing rods (4.5 m and 5.4 m). The age structure and growth characteristics of P. fluviatilis in the reservoir were analyzed. Results showed that the body length of the sampled fish ranged from 100.53 to 305.30 mm, with the dominant length group being 100.53–150.00 mm, accounting for 90.09% of the total. Body mass ranged from 24.20 to 490.20 g, with the dominant mass group below 66.5 g, accounting for 89.86%. The age composition of the population consisted of age classes 1–5, with ages 1–2 years old being dominant, accounting for 96.2% of the total samples. Among these, 1-year-old individuals were the most abundant, accounting for 78.3%, while older fish were relatively scarce. The relationship between body length (L_t) and body mass (W_t) was modeled as W_t = 4.298 × 10⁻⁵ L_t^2.85 (R² = 0.998, n = 296). The von Bertalanffy growth equations were L_t = 652.866 [1 − e^−0.108(^t+0.778)] and W_t = 4990.21 [1 − e^−0.108(^t+0.778)]^2.85, with a growth coefficient K = 0.108. The inflection point of growth was determined to be 1.9 years by fitting growth rate and acceleration equations. The b < 3 indicates allometric growth, where body length increases faster than body mass, suggesting that P. fluviatilis prioritizes elongating its body to enhance swimming ability and expand its range, while accumulating muscle and fat at a slower pace. Principal component analysis (PCA) revealed that the cumulative contribution rate of the first three principal components was 55.45%, reflecting the morphological characteristics of the species. The accuracy of discriminant analysis for sex determination based on external morphology was 67.20%, indicating limited reliability in gender identification using only morphological traits. Full article

Spectral reflectance of plants can be readily associated with physiological and biochemical parameters. Thus, relating spectral data to amino acid contents in different genetic materials provides an innovative and efficient approach for understanding and managing genetic diversity. Therefore, this study had two objectives: (I) to differentiate genetic materials according to amino acid contents and spectral reflectance; (II) to establish the relationship between amino acids and spectral bands derived from hyperspectral data. The research was conducted with 32 soybean genetic materials grown in the field during the 2023–2024 crop year. The experimental design involved randomized blocks with four replicates. Leaf spectral data were collected 60 days after plant emergence, when the plants were in full bloom. Three leaf samples were collected from the third fully developed trifoliate leaf, counted from top to bottom, from each plot. The samples were taken to the laboratory, where reflectance readings were obtained using a spectroradiometer, which can measure the 350–2500 nm spectrum. Wavelengths were grouped as means of representative intervals and then organized into 28 bands. Subsequently, the leaf samples from each plot were subjected to quantification analyses for 17 amino acids. Then, the soybean genotypes were subjected to a PCA–K-means analysis to separate the genotypes according to their amino acid content and spectral behavior. A correlation network was constructed to investigate the relationships between the spectral variables and between the amino acids within each group. The groups formed by the different genetic materials exhibited distinct profiles in both amino acid composition and spectral behavior. Leaf reflectance data proved to be efficient in identifying differences between soybean genotypes regarding the amino acid content in the leaves. Leaf reflectance was effective in distinguishing soybean genotypes according to leaf amino acid content. Specific and high-magnitude associations were found between spectral bands and amino acids. Our findings reveal that spectral reflectance can serve as a reliable, non-destructive indicator of amino acid composition in soybean leaves, supporting advanced phenotyping and selection in breeding programs. Full article

This study investigates urban life satisfaction and residents’ settlement intention as emergent outcomes of interconnected urban systems and examines the moderating role of urban regeneration budget execution as a systemic policy input. Drawing on the bottom-up spillover perspective and policy feedback theory, this study posits that satisfaction with core aspects of urban living—such as housing, transportation, and public safety—reflects the functioning of multiple interrelated urban subsystems, which accumulate into a global sense of well-being that influences settlement intention. Furthermore, when urban regeneration budgets are visibly and fully executed, they operate as institutional feedback mechanisms, leading residents to attribute their life satisfaction to effective system performance and reinforcing their desire to stay. Using survey data from Incheon Metropolitan City and Gyeonggi Province in South Korea, the study employs stereotype logistic regression to test the proposed model. The findings reveal that urban life satisfaction significantly predicts stronger settlement intention, and this effect is amplified in municipalities with higher levels of budget execution. These results contribute to theoretical understanding by linking subjective well-being with institutional performance and offer practical guidance for South Korean local governments seeking to strengthen community resilience through transparent and outcome-driven urban policy delivery. Full article

Beyond its renowned gemological value, diamond serves as a vital economic mineral and a unique messenger from Earth’s deep interior, preserving invaluable geological information. Since the Mengyin region is the source of China’s greatest diamond deposits, research on the diamonds there not only adds to our understanding of their origins but also offers an essential glimpse into the development of the North China Craton’s mantle lithosphere. In this article, 50 diamond samples from Mengyin were investigated using gemological microscopy, Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, DiamondView™, and X-ray micro-computed tomography (CT) scanning technologies. The types of Mengyin diamonds are mainly Type IaAB, Type IaB, and Type IIa, and the impurity elements are N and H. Inclusions in diamonds serve as direct indicators of mantle-derived components, providing crucial constraints on the pressure–temperature (P–T) conditions during their crystallization. Mengyin diamonds have both eclogite-type and peridotite-type inclusions. It formed at depths ranging from 147 to 176 km, which corresponds to source pressures of approximately 4.45–5.35 GPa, as determined by the Raman shifts of olivine inclusions. The discovery of coesite provides key mineralogical evidence for subduction of an ancient oceanic plate in the source region. The surface morphology of diamonds varies when they are reabsorbed by melts from the mantle, reflecting distinctive features that record subsequent geological events. Distinctive surface features observed on Mengyin diamonds include fusion pits, tile-like etch patterns, and growth steps. Specifically, regular flat-bottomed negative trigons are mainly formed during diamond resorption in kimberlite melts with a low CO₂ (X_CO2 < ~0.5) and high H₂O content. The samples exhibit varying fluorescence under DiamondView™, displaying blue, green, and a combination of blue and green colors. This diversity indicates that the diamonds have undergone a complex process of non-uniform growth. The nitrogen content of the melt composition also varies significantly throughout the different growth stages. The N3 center is responsible for the blue fluorescence, suggesting that it originated in a long-term, hot, high-nitrogen craton, and the varied ring band structure reveals localized, episodic environmental variations. Radiation and medium-temperature annealing produce H3 centers, which depict stagnation throughout the ascent of kimberlite magma and are responsible for the green fluorescence. Full article

This study compares the LEED, BREEAM, and WELL certification systems using the Triple Bottom Line (TBL) framework to assess their performance across environmental, social, and economic dimensions and their alignment with sustainable development goals. A structured secondary analysis was conducted on over 50 peer-reviewed articles, case studies, and official certification manuals. Inclusion criteria required documented design targets and post-occupancy outcomes for certified buildings (2014–2024). A two-phase analytical model was applied: first, evaluating each system’s structure and priorities; then benchmarking them using the TBL framework to assess how holistically each addresses sustainability. Results show that LEED leads to energy optimization, BREEAM to lifecycle integration, and WELL to occupant health and indoor environmental quality. However, all systems exhibit post-occupancy performance gaps: LEED and BREEAM underperform by 15–30% in energy use, while WELL-certified projects may exceed 30% due to stringent indoor comfort demands. These findings highlight the need to integrate real-time post-occupancy evaluation into certification protocols. To improve overall effectiveness, the study proposes enhancements such as adaptive performance tracking, occupant feedback loops, and dynamic benchmarking aligned with actual building use. By identifying both the comparative strengths and systemic limitations of the three frameworks, this research contributes to the refinement of green building assessment tools. Practical implications include (1) integrating post-occupancy evaluation into certification renewal cycles, (2) adopting hybrid certification strategies to improve sustainability coverage, and (3) designing benchmarking tools that reflect real-world operational data. Full article

A single-crystal magnesium oxide (MgO) dual-Fabry–Perot (FP)-cavity sensor based on MEMS technology and laser micromachining is proposed for simultaneous measurement of temperature and pressure. The pressure sensitive cavity is processed by wet chemical etching and direct bonding, which can improve machining efficiency, ensure the quality of the reflection surface and achieve thermal stress matching. Femtosecond laser and micromachining technologies are used to fabricate a rough surface and a through hole to reduce the reflect surface and fix the optical fiber. The bottom surface of the pressure cavity and the upper surface of the MgO wafer form a temperature cavity. A cross-correlation signal demodulation algorithm combined with a temperature decoupling method is proposed to achieve dual-cavity demodulation and eliminate the cross-sensitivity between temperature and pressure, improving the accuracy of pressure measurement. Experimental results show that the proposed sensor can stably operate at an ambient environment of 22–800 °C and 0–0.5 MPa with a pressure sensitivity of approximately 0.20 µm/MPa (room temperature), a repeatability error of 2.06% and a hysteresis error of 1.90%. After temperature compensation, thermal crosstalk is effectively eliminated and the pressure measurement accuracy is 2.01%F.S. Full article

This paper explores the concept of ephemeral cultural landscapes through the lens of public election advertising during the 2025 Australian Federal election in the regional city of Albury, New South Wales. Framing election signage as a transient cultural landscape, the study assesses the distribution of election signage (corflutes) disseminated by political candidates against demographic and socio-economic criteria of the electorate. The paper examines how corflutes and symbolic signage reflect personal agency, spatial contestation, and community engagement within urban and suburban environments. A detailed windscreen survey was conducted across Albury over three days immediately prior to and on election day, recording 193 instances of campaign signage and mapping their spatial distribution in relation to polling booth catchments, population density, generational cohorts, and socio-economic status. The data reveal stark differences between traditional party (Greens, Labor, Liberal) strategies and that of the independent candidate whose campaign was marked by grassroots support and creative symbolism, notably the use of orange corflutes shaped like emus. The independent’s campaign relied on personal property displays, signaling civic engagement and a bottom-up assertion of political identity. While signage for major parties largely disappeared within days of the election, many of the independent’s symbolic emus persisted, blurring the temporal boundaries of the ephemeral landscape and extending its visual presence well beyond the formal campaign period. The study argues that these ephemeral landscapes, though transitory, are powerful cultural expressions of political identity, visibility, and territoriality shaping public and private spaces both materially and symbolically. Ultimately, the election signage in Albury serves as a case study for understanding how ephemeral landscapes can materially and symbolically shape public space during moments of civic expression. Full article

This study presents a comprehensive analysis of the chemical composition of bottom ash samples generated during municipal waste incineration. A total of 52 samples were collected and subjected to statistical analysis for 17 elements and 2 element sums using techniques such as correlation analysis and one-way ANOVA. The results confirm a high degree of heterogeneity in the elemental content, reflecting the variability of waste streams and combustion processes. Strong correlations were identified between certain elements, including Cu-Zn, Co-Ni, and HREE-LREE, indicating common sources and similar geochemical properties. The analysis also revealed significant seasonal variability in the content of Ba and Sr, with lower average values observed during the spring season and greater variability noted during summer and winter. Although Al and HREE did not reach classical significance levels, their distributions suggest possible seasonal differentiation. These findings underscore the need for long-term monitoring and seasonal analysis of incineration bottom ash composition to optimize resource recovery processes and assess environmental risk. The integration of chemical data with operational data on waste composition and combustion parameters may contribute to a better understanding of the variability of individual elements, ultimately supporting the development of effective strategies for ash management and element recovery. Full article

This study focuses on Shanghai, a pioneer city in China’s community renewal practices. In recent years, community renewal driven by civic participation has become a prominent research topic, leading to the emergence of numerous exemplary cases in Shanghai. However, field investigations revealed that many projects have experienced varying degrees of physical deterioration and a decline in spatial vitality due to insufficient maintenance, reflecting unsustainable outcomes. In response, this study examines a bottom-up community renewal project led by the research team, aiming to explore how broad civic participation can promote sustainable community renewal. A multidisciplinary approach incorporating perspectives from ecology, the humanities, economics, and sociology was used to guide citizen participation, while participatory observation methods recorded emotional shifts and maintenance behavior throughout the process. The results showed that civic participatory actions under the guidance of sustainability principles effectively enhanced citizens’ sense of community identity and responsibility, thereby facilitating the sustainable upkeep and operation of community spaces. However, the study also found that bottom-up efforts alone are insufficient. Sustainable community renewal also requires top-down policy support and institutional safeguards. At the end, the paper concludes by summarizing the practical outcomes and proposing strategies and mechanisms for broader application, aiming to provide a reference for related practices and research. Full article

This study develops a novel transverse steel damper (TSD) to enhance the seismic performance of tall-pier girder bridges, featuring superior lateral strength and energy dissipation capacity. The TSD’s design and arrangement are presented, with its hysteretic behavior simulated in ABAQUS. Key parameters (yield strength: 3000 kN; initial gap: 100 mm; post-yield stiffness ratio: 15%) are optimized through seismic analysis under near-fault ground motions, incorporating pulse characteristic investigations. The optimized TSD effectively reduces bearing displacements and results in smaller pier top displacements and internal forces compared to the bridge with fixed bearings. Due to the higher-order mode effects, there is no direct correlation between top displacements and bottom internal forces. As pier height decreases, the S-shaped shear force and bending moment envelopes gradually become linear, reflecting the reduced influence of these modes. Medium- to long-period pulse-like motions amplify seismic responses due to resonance (pulse period ≈ fundamental period) or susceptibility to large low-frequency spectral values. Higher-order mode effects on bending moments and shear forces intensify under prominent high-frequency components. However, the main velocity pulse typically masks the influence of high-order modes by the overwhelming seismic responses due to large spectral values at medium to long periods. Full article

Simulation is an important technical tool in corn threshing operations, and the establishment of the corn kernel model is the core part of the simulation process. The existing modeling method is to treat the whole kernel as a rigid body, which cannot be crushed during the simulation process, and the calculation of the crushing rate needs to be considered through multiple criteria such as the contact force, the number of collisions, and so on. Aiming at the issue that kernel crushing during maize threshing cannot be accurately modeled in discrete element simulations, in this study, a sub-area crushing model was constructed; representative samples with 26%, 30% and 34% moisture content were selected from a double-season maturing region in China; based on the physical dimensions and biological structure of the maize kernel, three stress regions were defined; and mechanical property tests were conducted on each of the three stress regions using a texturometer as a way to determine the different crushing forces due to the heterogeneity of the maize structure. The correctness of the model was verified by stacking angle and mechanical property experiments. A discrete element model of corn kernels was established using the Bonding V2 method and sub-area modeling. Bonding parameters were calculated by combining stacking angle tests and mechanical property tests. The flattened corn kernel was used as a prototype, and the bonding parameters were determined through size and mechanical property tests. A 22-ball bonding model was developed using dimensional parameters, and the kernel density was recalculated. Results showed that the relative error between the stacking angle test and the measured mean value was 0.31%. The maximum deviation of axial compression simulation results from the measured mean value was 22.8 N, and the minimum deviation was 3.67 N. The errors between simulated and actual rupture forces at the three force areas were 5%, 10%, and 0.6%, respectively. The decreasing trend of the maximum rupture force for the three moisture levels in the simulation matched that of the actual rupture force. The discrete element model can accurately reflect the rupture force, energy relationship, and rupture process on both sides, top, and bottom of the grain, and it can solve the error problem caused by the contact between the threshing element and the grain line in the actual threshing process to achieve the design optimization of the threshing drum. The modeling method provided in this study can also be applied to breakable discrete element models for wheat and soybean, and it provides a reference for optimizing the design of subsequent threshing devices. Full article