Abstract ：

The impact of carbon/nitrogen (C/N) ratio on sequencing batch biofilm reactor (SBBR) initiated with different seed sludges for treating actual mariculture effluent was explored. Increasing the C/N ratio significantly enhanced the nitrogen removal efficiency, achieving average removal efficiency of 95% for ammonia nitrogen and 73% for total nitrogen at ratio of 30, while the impact of seed sludge was minimal. High C/N ratio promoted the secretion of tightly bound extracellular polymeric substances (TB-EPS), which showed significant correlation with nitrogen removal. Interactions between bacteria and archaea were enhanced and conditionally rare or abundant taxa were the keystone taxa. High C/N ratio inhibited the relative abundance of ammonia-oxidizing archaea (Candidatus_Nitrosopumilus) and bacteria (Nitrosomonas), but promoted the heterotrophic nitrification-aerobic denitrification bacteria (Halomonas). The expression of nitrogen removal functional genes significantly correlated with functional genera. This study emphasized the crucial role of high C/N ratios in biological nitrogen removal from actual mariculture effluent. © 2024 Elsevier Ltd

Keyword ：

Mariculture effluent Bacteria/archaea Carbon/nitrogen ratio Functional genera Nitrogen removal

Cite：

Copy from the list or Export to your reference management。

Abstract ：

The rapid advancement of spectrally selective materials has enabled the development of smart windows that can regulate different bands of solar radiation. However, existing methods for calculating spectral properties vary, leading to inconsistent results when evaluating their light-electricity-heat-color performance. Therefore, this paper presents five methods for calculating window spectral properties, intending to compare and identify the most effective approach for assessing building thermal performance, energy efficiency, and daylighting. The methods focus primarily on the solar spectrum input and the glazing spectrum response. The solar spectrum inputs include the Beijing local solar spectrum, ASTM G173-03, and ISO 9845 (methods S1 to S3), and the glazing spectrum response methods differ based on whether they account for spectral selectivity and the choice of spectral weighting functions (methods S3 to S5). The findings reveal that variations in solar spectrum input have a minimal effect on window performance, while differences in glazing spectral response calculations significantly impact results. It is particularly evident in thermochromic windows, where discrepancies in energy efficiency, specifically in lighting load, can reach up to 67.21 %, and variations in dynamic daylighting performance, specifically in Useful Daylight Illuminance (UDI) below 500 lx, can be as high as 28.27 %. To provide more accurate assessment results of glazing windows, this study recommends using the spectral calculation method S1, which incorporates the local solar spectrum and applies the standard luminous efficiency function to the glazing spectrum response. This paper highlights that further refinement of spectral calculation methods will enhance their utility for performance evaluation and guide the reverse design of innovative window features. © 2024 Elsevier Ltd

Keyword ：

Solar spectrum Performance evaluation Optical property Glazing spectrum response Glazing window

Cite：

Copy from the list or Export to your reference management。

Abstract ：

Motivated by advances in spintronic devices, extensive explorations are underway to uncover materials that host topologically protected spin textures, exemplified by skyrmions. One critical challenge involved in the potential application of skyrmions in van der Waals (vdW) materials is the attainment and manipulation of skyrmions at room temperature. In this study, we report the creation of an intrinsic skyrmion state in the van der Waals ferromagnet Fe3GaTe2. By employing variable temperature magnetic force microscopy, the skyrmion lattice can be locally manipulated on Fe3GaTe2 flakes. The ordering of skyrmion state is further analyzed. Our results suggest Fe3GaTe2 emerges as a highly promising contender for the realization of skyrmion-based layered spintronic memory devices. © 2024 The Authors

Keyword ：

Fe3GaTe2 van der Waals magnet Skyrmion lattice

Cite：

Copy from the list or Export to your reference management。

Abstract ：

Introduction: The issue of population aging is increasingly prominent, presenting unprecedented challenges and pressures on urban medical resources. The equity and convenience of medical services for older adults have emerged as critical concerns for urban planners. While previous research on medical accessibility for older adults has yielded fruitful results, it has lacked a thorough analysis of the quantitative relationship between revealed and potential accessibility across urban spaces, as well as the influencing factors leading to the spatial heterogeneity of these two types of accessibility. Methods: This study calculates the ratio of revealed to potential accessibility based on multi-source data, thereby identifying the allocation of medical resources in different sub-districts in Beijing. Furthermore, an extreme gradient boosting model is used to investigate the non-linear associations between the potential influencing factors and the ratio of revealed to potential accessibility. Results: The results revealed a significant spatial disparity between potential accessibility and revealed accessibility and identified the threshold effects of influencing factors contributing to the accessibility ratio of revealed to potential accessibility. The density of bus stops, vehicle ownership, and density of roads are the top three among the influencing factors in terms of their relative importance in influencing the accessibility ratio. Conclusions: The threshold effect should be considered when implementing planning adjustments, as simply increasing or decreasing the values of specific built environment variables may not result in a corresponding improvement in medical accessibility for older adults. With limited resources, enhancing the planning and construction of transportation infrastructure is more efficient in reducing the discrepancy between revealed accessibility and potential accessibility compared to other methods. © 2024 Elsevier Ltd

Keyword ：

Transportation planning Population aging Medical accessibility Non-linear analysis Machine learning

Cite：

Copy from the list or Export to your reference management。

Abstract ：

The seismic performance of underground structures is strongly influenced by the characteristics of both the surrounding soil and the earthquake. In contrast to traditional deterministic analysis methods, this study uses a stochastic analysis approach to investigate the effect of uncertainties in nonlinear soil characteristics, shear wave velocity, density, and earthquake randomness on the response of underground stations. The equivalent linearization method is employed to approximate the nonlinear behavior of the soil. The soil was modeled using a linear elastic constitutive model combined with Rayleigh damping in the finite element model. Inter-story displacements are used to determine structural damage. Probabilistic analysis methods are used to obtain their statistical characteristics, and the probability of failure is calculated. The results show that, according to single parameter analysis, random ground motion results in the greatest probability of exceeding the threshold (PET), while ground shear wave velocity significantly affects the coefficient of variation (COV), and the effect of density is the smallest. The study also found that when soil nonlinearity, shear wave velocity, and random ground motion are considered simultaneously, the range, mean, standard deviation, and COV of interstory displacement all increase significantly, but the PET slightly decreases. In summary, the analysis results indicate that random ground motion has the greatest impact on interstory displacement, followed by shear wave velocity, with nonlinear soil characteristics having a smaller effect, and density the least. Therefore, the impact of various uncertainties should be fully considered in the analysis of underground structures, especially random ground motion and shear wave velocity. © 2024 Elsevier Ltd

Keyword ：

Underground structures Probabilistic analysis Random ground motion Density Shear wave velocity Nonlinear soil characteristics

Cite：

Copy from the list or Export to your reference management。

Abstract ：

A self-centering prestressed beam-column connection (SCPBCC) with weakened flange cover plate (FCP) is proposed to achieve self-centering features and post-earthquake recoverability at reasonable cost. The self-centering and energy dissipation capacity of SCPBCC are controlled respectively by the prestressed cable and FCP, and the bearing capacity of SCPBCC is controlled by adjusting the bearing ratio of the cable and FCP. Five SCPBCC specimens were subjected to large and small-amplitude, cyclic-loading tests. The test results demonstrated that the new SCPBCC can meet requirements of stiffness and strength, achieve excellent self-centering features, survive multiple aftershocks and allows for replacement. The connection can supply ample energy dissipation through cyclic yielding of the FCPs. Reasonable variable section and limited prestress can protect beams and the column from plastic deformation. The proposed design methodology ensures good bearing and self-resetting capacity for SCPBCCs. © 2024 Elsevier Ltd

Keyword ：

Low-cycle fatigue loading test Energy dissipation Seismic behavior Beam-to-column connections Self-centering systems Prestressed cable

Cite：

Copy from the list or Export to your reference management。

Abstract ：

In this article, the 3D Voigt-regularized Magnetohydrodynamic equations are considered, for which it is unknown if the uniqueness of weak solution exists. First, we prove that the uniform global attractor exists by constructing an evolutionary system. Then singular limits of this system are established. Namely, when a certain regularization parameter disappears, the convergence of global attractors is shown between the 3D autonomous Voigt-regularized Magnetohydrodynamic equations and Magnetohydrodynamic equations. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.

Keyword ：

Magnetohydrodynamic equations 37L30 76A10 76D99 35B40 Tracking property Evolutionary system 35Q35 Singular limits Global attractor

Cite：

Copy from the list or Export to your reference management。

Abstract ：

The poor adhesion of asphalt-granite limits the application of granite. This research aims to enhance the adhesion of asphalt and granite by establishing chemical connections between the hydroxyl groups on granite surface and the incompletely reacted isocyanate groups in polyurethane (PU) modified asphalt. For this purpose, end-capped PU modified asphalt (PUMA) was prepared, the adhesion mechanism between PUMA and granite was analyzed by Raman spectroscopy, the adhesion properties between PUMA and granite at different curing periods were evaluated by boiling and pull-out tests, and the wettability of PUMA on granite and its moisture sensitivity were evaluated using surface free energy (SFE) method. The findings suggested that the incompletely reacted isocyanate groups in PUMA can establish a chemical connection with the hydroxyl groups on the surface of granite. The adhesion between asphalt and granite can be greatly improved by the addition of PU, and this improvement is amplified as the curing time is extended. When the curing time is extended to 3 days, the fracture mode between asphalt and granite changed from adhesive failure to cohesive failure, and after 15 days of curing, the coating ratio of PUMA on granite following the water boiling test can be raised by 28.11% in comparison to the base asphalt. The water damage resistance of PUMA-granite system can be increased by adding PU and the adhesion work and combination ratio of the freshly prepared PUMA were increased by 55.91% and 79.45%, respectively, as compared to base asphalt. This study has great significance for enhancing the adhesion between asphalt and granite and encouraging granite application. © 2024 American Society of Civil Engineers.

Keyword ：

Granite End-capped polyurethane Interfacial adhesion Polyurethane modified asphalt (PUMA)

Cite：

Copy from the list or Export to your reference management。

Abstract ：

Urban green spaces (UGS) can mitigate urban waterlogging disasters and improve subjective well-being. The study presents an integrated framework combining subjective and objective perceptions to assess the socio-economic value of UGS, using InfoWorks ICM model and the Life Satisfaction Approach. Central Beijing was selected as a case study. From the objective perception perspective, UGS significantly mitigated waterlogging risks, particularly in low and high rainfall return periods, with green space hotspots overlapping with areas of severe waterlogging risk. From the subjective perception perspective, women, younger groups, and non-car owners perceived a stronger relationship between UGS and waterlogging based on CGSS 2021. The waterlogging mitigation value of UGS was largely undervalued, with 67.33 % of the total value coming from indirect effects. During the 5-year rainfall return period, the reasonable threshold of UGS area was 33.36 km², and each household was willing to pay 1.3468 RMB/m2 ($0.1921). © 2024 Elsevier B.V.

Keyword ：

Urban waterlogging;Urban green spaces;Willingness to pay;Subjective well-being;Perceived value;InfoWorks ICM model

Cite：

Copy from the list or Export to your reference management。

Abstract ：

Cluster analysis is an essential method in machine learning, primarily used in situations with crisp data. However, data obtained in practice can be imprecise, forcing classic clustering methods to fail. Spurred by this constraint, this paper introduces an uncertain c-means clustering method, which employs uncertain variables to characterize imprecise observations based on the uncertainty theory. Specifically, we define a distance from an uncertain variable to a crisp vector and introduce an uncertain partition method. Additionally, according to the distance and partition method, an uncertain clustering is proposed. Finally, numerical experiments demonstrate the effectiveness of the proposed method. © 2024

Keyword ：

Imprecise observations Uncertain clustering method Uncertain variable

Cite：

Copy from the list or Export to your reference management。