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Based on undrained cyclic simple shear tests conducted on coastal tidal soft soil under various conditions of cyclic stress ratios and moisture contents, this study investigated the influence of these factors on the dynamic properties of the soil. The findings indicated that with increasing moisture content and stress cycle ratio, the stress–strain hysteresis loop gradually expanded, resulting in a higher strain difference and a transition from a dense to a sparse curve pattern. Moreover, the symmetry of the hysteresis loop was lost in the later stages of shearing. With an increase in the number of cycles, the cumulative shear strain gradually increased, and the increase in the cyclic ratio of water content to stress reduced the number of cyclic shear cycles required to achieve failure, thereby accelerating the soil's failure rate. A predictive formula was developed based on the experimental results to estimate the failure cycles as a function of the cyclic stress ratio and moisture content. Furthermore, the softening index decreased gradually with an increasing number of cycles, and a higher moisture content and cyclic stress ratio accelerated the soil's softening process. It was observed that under the conditions of optimal moisture content, the soil exhibited a slower softening rate during the initial stage of shearing. [ABSTRACT FROM AUTHOR]

In this study, the rolling process of the warm-rolled duplex-phase Mg–8.3Li–3.1Al–1.09Si alloy and the strengthening mechanism of as-rolled Mg–Li alloy were investigated. The highest ultimate tensile strength (UTS, 323.66 ± 19.89 MPa) could be obtained using a three-pass rolling process with a 30% thickness reduction for each pass at 553 K. The strength of the as-rolled LAS831 alloy is determined by a combination of second-phase strengthening, grain refinement strengthening, dislocation strengthening, and load-transfer reinforcement. Of these factors, dislocation strengthening, which is caused by strain hardening of the α-Mg phase, can produce a good strengthening effect but also cause a decrease in plasticity. The Mg2Si phase is broken up into particles or strips during the rolling process. After three passes, the AlLi particles were transformed into an AlLi phase, and the Mg2Si particles and nanosized AlLi particles strengthened the second phase to form a hard phase. The average size of the DRXed β-Li grains decreased with each successive rolling pass, and the average size of recrystallized grains in the three-pass-rolled LAS831 alloy became as low as 0.27 μm. The interface between the strip-like Mg2Si phase and the α-Mg phase is characterized by semicoherent bonding, which can promote the transfer of tensile and shear forces from the matrix to the strip-like Mg2Si phase, thereby improving the strength of the matrix and thus strengthening the LAS831 alloy. [ABSTRACT FROM AUTHOR]

Nowadays, the use of new compound chemical stabilizers to treat marine clay has gained significant attention. However, the complex non-linear relationship between the influencing factors and the unconfined compressive strength of chemically treated marine clay is not clear. In order to study the influence of various factors (dosage, type of stabilizer, curing age) on the unconfined compressive strength of solidified soil during chemical treatment, experiments were performed to determine the unconfined compressive strength of soft marine clay modified with various types of stabilizers. Further, an artificial neural network (ANN) model was used to establish a prediction model based on the unconfined compressive strength test data and to verify the performance. Sensitivity and optimization analyses were further conducted to explore the relative significance of parameters as well as the optimal dosage amount. Research has found that when the content of aluminate cement is 89.5% and the content of curing agent is 30%, the unconfined compressive strength significantly increases after 28 days of solidification, and the change in quicklime content has the greatest effect on the improvement in the unconfined compressive strength. The influence of modifiers on the unconfined compressive strength is in the order: potassium hydroxide > kingsilica > quick lime > bassanite. The values of each factor were obtained when the unconfined compressive strength was the maximum, which provided support for the optimization of the treatment scheme. The analysis of chemical treatment is no longer limited to the linear relationship according to the test results, which proves the feasibility of non-linear relationship analysis based on the artificial neural network. [ABSTRACT FROM AUTHOR]

Multifunctional nanoparticles are of significant importance for synergistic multimodal antitumor activity. Herein, zinc oxide (ZnO) was used as pH-sensitive nanoparticles for loading the chemotherapy agent doxorubicin (DOX) and the photosensitizer agent indocyanine green (ICG), and biocompatible low-molecular-weight heparin (LMHP) was used as the gatekeepers for synergistic photothermal therapy/photodynamic therapy/chemotherapy/immunotherapy. ZnO was decomposed into cytotoxic Zn2+ ions, leading to a tumor-specific release of ICG and DOX. ZnO simultaneously produced oxygen (O2) and reactive oxygen species (ROS) for photodynamic therapy (PDT). The released ICG under laser irradiation produced ROS for PDT and raised the tumor temperature for photothermal therapy (PTT). The released DOX directly caused tumor cell death for chemotherapy. Both DOX and ICG also induced immunogenic cell death (ICD) for immunotherapy. The in vivo and in vitro results presented a superior inhibition of tumor progression, metastasis and recurrence. Therefore, this study could provide an efficient approach for designing multifunctional nanoparticles for synergistic multimodal antitumor therapy. [ABSTRACT FROM AUTHOR]

High-temperature compression tests on Mg-11.5Li-2.5Zn-0.35Al-0.3Y (in wt.%) were carried out on a Gleeble-3500 thermal simulator. Flow stress and microstructural evolution were analyzed at different temperatures (T = 473 K, 523 K, 573 K, and 623 K) and strain rates ( ε ˙ = 1 s−1, 0.1 s−1, 0.01 s−1, and 0.001 s−1). On this basis, the constitutive model of the alloy was established using the Arrhenius-type constitutive model, and the thermal processing map of the alloy was drawn based on the DMM (dynamic material modeling) theory. The experimental results show that the flow stress of the Mg-11.5Li-2.5Zn-0.35Al-0.3Y alloy decreases with an increase in temperature and a decrease in strain rate. The grain size increases uniformly with the increase in temperature, while a sudden increase occurs with the decrease in strain rate. The predicted value of the model is compared with the experimental value to verify the correctness of the model, and the correlation coefficient, R = 0.9690, was calculated, which further proves the applicability of the model to the Mg-11.5Li-2.5Zn-0.35Al-0.3Y alloy. This alloy can be safely plastic-deformed 473 K~623 K and 0.001 s−1~1 s−1. [ABSTRACT FROM AUTHOR]

Understanding the stability of the seabed foundation holds paramount significance in guaranteeing the safety and structural soundness of the breakwater alongside additional offshore structures. This study aimed to investigate the stability of a sandy seabed foundation around a semi-circular breakwater under wave loading in nearshore areas. A coupled numerical model of waves, a semi-circular breakwater, and the seabed was developed based on the OpenFOAM platform. The VARANS equations were used to govern the wave behavior. Meanwhile, the Biot's partially dynamic model was employed to numerically simulate the seabed response considering both consolidation under self-weight and dynamic response under wave loading. The effects of various wave parameters, seabed properties, and the radius of the structure on the dynamic response of the seabed and the depth of liquefaction were investigated. The numerical results indicate that an increase in wave height, period, and permeability coefficient intensifies the dynamic response of the seabed soil. Furthermore, an increase in water depth weakened the soil's dynamic response. There was a negative correlation between the radius of the semi-circular breakwater and the dynamic response. The influence of Poisson's ratio on the dynamic response of the seabed was relatively small. Furthermore, a stronger dynamic pore pressure response was observed at the connection between the semi-circular breakwater and the rubble foundation. [ABSTRACT FROM AUTHOR]

To examine the effects of different peak accelerations on the stability of the accumulation slope and the effectiveness of anti-slide piles under seismic loads, this paper used the Fanlingqian landslide as the main research object and combined it with digital image correlation (DIC) technology in order to carry out a shaking table test. Then, the acceleration response, displacement field, strain field, the bending moment distribution of the 0.05–0.3 g ground motion accumulation slope, and the anti-slide pile reinforcement were studied. The results of the test show the following: the amplification coefficient of the measuring points A1–A6 of the accumulation slope reaches the maximum at a peak acceleration of 0.2 g, and its values are between 1.25 and 1.3, respectively. Finally, it shows a decreasing trend at a peak acceleration of 0.3 g, and its corresponding values are, respectively, between 1.1 and 1.2. In the anti-slip pile reinforcement test, due to the obstruction of the anti-slip pile, the damping of the soil around the pile increases. As the peak value of the seismic wave input increases, the amplification factor shows an overall decreasing trend. A1–A6 correspond to a peak acceleration of 0.3 g. The amplification factors are all close to 1. During different peak accelerations, the accumulation slope mainly experienced the earthquake-induced stage, tensile failure stage, creeping deformation stage, and overall instability stage. In the anti-slide pile reinforcement test, under the same conditions, the slope mainly experienced the earthquake-induced stage, tensile failure stage, lower sliding surface formation stage, and soil shedding stage in front of the pile. At the same time, the displacement and strain fields of each stage of the two groups of tests are compared, and it is found that the displacement and strain values of the accumulation slope test are greater than those of the anti-slide pile reinforcement test, and the horizontal displacement difference at the top of the slope is the most significant, reaching 2.3 times at the maximum. The bending moment of the anti-slide pile first increases and then decreases with the increase in acceleration, the reverse bending point of the pile appears at 5 times the pile diameter below the soil surface, and the maximum bending moment of the middle pile, corresponding to a peak acceleration of 0.05–0.3 g, is between 7.5 N·m and 47 N·m, respectively, while the maximum bending moment of the outer pile is between 6.5 N·m and 52 N·m, respectively. It is important to apply DIC image processing technology to the monitoring of landslide structure and the evaluation of slope stability in practical engineering. [ABSTRACT FROM AUTHOR]

The auxin/indole-3-acetic acid (Aux/IAA) gene family plays a critical role in auxin-mediated responses and fruit development. However, studies on its role in watermelon are limited. In this study, 29 ClIAA gene members were identified in the watermelon genome and classified into eleven groups. Of note, ClIAA16, which was found to be up-regulated during fruit ripening, was targeted using CRISPR/Cas9 gene editing. Knockout mutants of ClIAA16 exhibited a 3–4 day delay in ripening compared to the wild type, highlighting the regulatory importance of ClIAA16. Our findings shed light on the importance of ClIAA genes in watermelon fruit ripening and pave the way for further functional studies. [ABSTRACT FROM AUTHOR]

The red color of apple peel is an important phenotypic and economic trait mainly attributed to anthocyanin accumulation. Apples show a deeper red color at higher altitudes than at lower ones; however, the molecular regulatory network underlying color variation along altitudinal gradients has not been investigated. In this study, the effects of environmental conditions associated with low (124 m) and high (1901 m) altitudes on peel color were assessed through physiological, metabolomic, transcriptomic, and qRT-PCR analyses in Huashuo apple and its sister line, Huarui apple. The content of cyanidin-3-O-galactoside, cyanidin-3-O-arabinoside, and cyanidin-3-O-xyloside was abundant in the high-altitude environment and may contribute to the deeper red color. Transcript levels of structural genes in the anthocyanin synthesis pathway, especially MdCHI, MdCHS, MdANS, and MdDFR, in apple peel were significantly higher at high altitude than at low altitude. Based on the protein interaction prediction and correlation analyses, four transcription factors (MDP0000127691, MDP0000284922, MDP0000758053, and MDP0000074681) could interact with anthocyanin synthesis-related proteins, showing high correlation with anthocyanin accumulation. Therefore, the abovementioned four genes and four transcription factors were predicted to account for the color differences between high and low altitudes. These results provide genetic resources and a theoretical basis for color-oriented fruit improvement. [ABSTRACT FROM AUTHOR]

To address the problems of difficult online monitoring, low recognition efficiency and the subjectivity of work condition identification in mineral flotation processes, a foam flotation performance state recognition method is developed to improve the issues mentioned above. This method combines multi-dimensional CNN (convolutional neural networks) characteristics and improved LBP (local binary patterns) characteristics. We have divided the foam flotation conditions into six categories. First, the multi-directional and multi-scale selectivity and anisotropy of nonsubsampled shearlet transform (NSST) are used to decompose the flotation foam images at multiple frequency scales, and a multi-channel CNN network is designed to extract static features from the images at different frequencies. Then, the flotation video image sequences are rotated and dynamic features are extracted by the LBP-TOP (local binary patterns from three orthogonal planes), and the CNN-extracted static picture features are fused with the LBP dynamic video features. Finally, classification decisions are made by a PSO-RVFLNs (particle swarm optimization-random vector functional link networks) algorithm to accurately identify the foam flotation performance states. Experimental results show that the detection accuracy of the new method is significantly improved by 4.97% and 6.55%, respectively, compared to the single CNN algorithm and the traditional LBP algorithm, respectively. The accuracy of flotation performance state classification was as high as 95.17%, and the method reduced manual intervention, thus improving production efficiency. [ABSTRACT FROM AUTHOR]

Accurate and rapid identification of mineral foam flotation states can increase mineral utilization and reduce the consumption of reagents. The traditional flotation process concentrates on extracting foam features from a single-modality foam image, and the accuracy is undesirable once problems such as insufficient image clarity or poor foam boundaries are encountered. In this work, a classification method based on multi-modality image fusion and CNN-PCA-SVM is proposed for work condition recognition of visible and infrared gray foam images. Specifically, the visible and infrared gray images are fused in the non-subsampled shearlet transform (NSST) domain using the parameter adaptive pulse coupled neural network (PAPCNN) method and the image quality detection method for high and low frequencies, respectively. The convolution neural network (CNN) is used as a trainable feature extractor to process the fused foam images, the principal component analysis (PCA) reduces feature data, and the support vector machine (SVM) is used as a recognizer to classify the foam flotation condition. After experiments, this model can fuse the foam images and recognize the flotation condition classification with high accuracy. [ABSTRACT FROM AUTHOR]

Loosened rock circle is formed around the tunnel when the tunnel is constructed by the drilling and blasting method. The size of the loosened rock circle around the tunnel and the degree of internal rock fragmentation has an important influence on the support parameters, durability, and safety of the tunnel. Firstly, referencing an existing tunnel project, blasting tests using nonelectronic and electronic detonators were carried out to determine the influence of blasting construction on the scope of the rock loose circle and the degree of rock fragmentation. Then, a numerical simulation was used to study the contribution of the blasting impact and surrounding rock stress redistribution on the loosened rock circle around the tunnel. The results showed that the range of the loosened rock circle around the tunnel generated by the normal blasting of nonelectronic detonators was 1.5~2.3 m, and the wave velocity of the rock mass in the loosened rock circle around the tunnel decreased to 23~36%. The size of the loosened rock circle around the tunnel generated by the blasting impact was 0.66 m, accounting for 33% of the range of the loosened rock circle around the tunnel. The range of the loosened rock circle around the tunnel produced by electronic detonator blasting was 0~1.4 m. The wave velocity of the rock mass in the loosened rock circle around the tunnel decreased to 12~17%. The range of the loosened rock circle around the tunnel was approximately 60~76% of that of detonator blasting, and the broken degree of the surrounding rock in the loosened rock circle around the tunnel was small. The research results can provide a reference for the optimization design of preliminary support parameters of tunnels, such as anchors and steel arches in blasting construction. [ABSTRACT FROM AUTHOR]

Bioinspired surfaces with special wettabilities attract increasing attention due to their extensive applications in many fields. However, the characterizations of surface wettability by contact angle (CA) and sliding angle (SA) have clear drawbacks. Here, by using an array of triangular micropillars (ATM) prepared by soft lithography, the merits of measuring the friction force of a water droplet on ATM over measurements of CA and SA in characterizing the surface wettability are demonstrated. The CA and SA measurements show ignorable differences in the wettabilities of ATM in opposite directions (1.13%) and that with different periodic parameters under the elongation ranging from 0 to 70%. In contrast, the friction measurement reveals a difference of > 10% in opposite directions. Moreover, the friction force shows a strong dependence on the periodic parameters which is regulated by mechanical stretching. Increasing the elongation from 0 to 50% increases the static and kinetic friction force up to 23.0% and 22.9%, respectively. Moreover, the stick-slip pattern during kinetic friction can reveal the periodic features of the measured surface. The friction force measurement is a sensitive technique that could find applications in the characterization of surface wettabilities. [ABSTRACT FROM AUTHOR]

Red coloration in apples, an important quality trait, is primarily attributed to the accumulation of anthocyanins. Centuries of breeding have produced a wide variety of apples with different levels of anthocyanins in response to genetic and environmental stimuli. The Huashuo apple shows a much darker red color than its sister line, Huarui. Thirteen different anthocyanins were detected in Huashuo and Huarui apples, of which ten were significantly more abundant in Huashuo apples, confirming that the color difference is indeed attributed to high anthocyanins accumulation rather than the types of anthocyanins. In particular, the contents of cyanidin 3-O-galactoside levels were highest among anthocyanins in both cultivars, reaching >5000 μg·g−1 at the last color transition stage in Huashuo apples, while only >3000 μg·g−1 in Huarui apples. Moreover, the expression of most structural genes, especially DFR, CHI, and 4CL associated with anthocyanin synthesis, were higher in Huashuo apples than in Huarui apples. Combined transcriptomics, metabolomics, and qRT-PCR analysis revealed that six transcription factors from the MYB and bZIP transcription factor families likely play key roles in the dark coloring of Huashuo apples. These results provide deeper insights into apple coloring and suggest a series of candidate genes for breeding anthocyanin-rich cultivars. [ABSTRACT FROM AUTHOR]

In recent years, hydrogels have been widely used as drug carriers, especially in the area of protein delivery. The natural silk fibroin produced from cocoons of the Bombyx mori silkworm possesses excellent biocompatibility, significant bioactivity, and biodegradability. Therefore, silk fibroin-based hydrogels are arousing widespread interest in biomedical research. In this study, a process for extracting natural silk fibroin from raw silk textile yarns was established, and three aqueous solutions of silk fibroin with different molecular weight distributions were successfully prepared by controlling the degumming time. Silk fibroin was dispersed in the aqueous solution as "spherical" aggregate particles, and the smaller particles continuously accumulated into large particles. Finally, a silk fibroin hydrogel network was formed. A rheological analysis showed that as the concentration of the silk fibroin hydrogel increased its storage modulus increased significantly. The degradation behavior of silk fibroin hydrogel in different media verified its excellent stability, and the prepared silk fibroin hydrogel had good biocompatibility and an excellent drug-loading capacity. After the protein model drug BSA was loaded, the cumulative drug release within 12 h reached 80%. We hope that these investigations will promote the potential utilities of silk fibroin hydrogels in clinical medicine. [ABSTRACT FROM AUTHOR]

The removal of soil during scouring is crucial to the lateral resistance of piles in bridges of railways or highways. In this process, dilatancy of the interface soil induces variation in normal stress, which in turn influences the interface soil lateral resistance. Due to the lack of analysis in previous studies in terms of cohesionless soil state (i.e., relative density and stress level) in remaining soil after scouring, it is difficult to simulate the properties and behavior of interface soil. The objective of this study is to explain the change of the sand state at the compression interface after scouring, quantify the stress-strain characteristics of the pile during this period and eventually present the prediction p-y curves of the lateral service capacity. The state-dependent constitutive model for saturated sand is employed, combined with the 3D finite element simulation, and the state development of the remaining soil is exhibited. The enhancement of dilation and stress relief of the remaining shallow horizon eventually gives rise to the reduction of the lateral resistance. In addition, the remaining overburden soil surrounding the pile restricts the interface soil, enlarging the normal stress and strengthening the deep horizon. Then, the friction angle considered the influence of state-dependent changes is used to quantify the hyperbolic p-y curves. [ABSTRACT FROM AUTHOR]

The hot deformation and dynamic recrystallization behavior of the dual-phase Mg-9Li-3Al-2Sr-2Y alloy had been investigated using a compression test. The typical dual-phase structure was observed, and average of grain size of as-homogenized alloy is about 110 µm. It mainly contains β-Li, α-Mg, Al4Sr and Al2Y phases. The dynamic recrystallization (DRX) kinetic was established based on an Avrami type equation. The onset of the DRX process occurred before the peak of the stress--strain flow curves. It shows that the DRX volume fraction increases with increasing deformation temperature or decreasing strain rate. The microstructure evolution during the hot compression at various temperatures and strain rates had been investigated. The DRX grain size became larger with the increasing testing temperature or decreasing strain rate because the higher temperature or lower strain rate can improve the migration of DRX grain boundaries. The fully recrystallized microstructure can be achieved in a small strain due to the dispersed island-shape α-Mg phases, continuous the Al4Sr phases and spheroidal Al2Y particles, which can accelerate the nucleation. The continuous Al4Sr phases along the grain boundaries are very helpful for enhancing the corrosion resistance of the duplex structured Mg-Li alloy, which can prevent the pitting corrosion and filiform corrosion. [ABSTRACT FROM AUTHOR]

This paper analyses the fluid–seabed–structure interactions (FSSI) around the open-ended pile by applying the in-house solver established on the open-source Computational Fluid Dynamics (CFD) platform. The Reynolds-averaged Navier–Stokes (RANS) equations are solved to simulate the hydrodynamic interactions between waves and open-ended piles. Biot's poro-elastic theory (quasi-static model) is used to reproduce the wave-induced seabed responses. The parameter analysis indicates that the wave period, degree of saturation of seabed and pile diameter have a great influence on the development of the transient seabed liquefaction depth around the pile. In addition, the distribution of the pore water pressure vs soil depth in the inner zone of the pile presents a "V" shape rotated 90 degrees counterclockwise. [ABSTRACT FROM AUTHOR]

The offshore wind energy (OWE) pile foundation is mainly a large diameter open-ended single pile in shallow water, which has to bear long-term horizontal cyclic loads such as wind and waves during OWE project lifetime. Under the complex cyclic loads, the stress and displacement fields of the pile-soil system change continuously, which affects the dynamic characteristics of the pile foundation. Within the service life of the pile foundation, the pile-soil system has irreversible cumulative deformation, which further causes damage to the whole structure. Therefore, it is important to examine the overall dynamic characteristics of wind power foundation under high cycle. In this paper, in the dry sand foundation, taking the Burbo Bank 3.6 MW offshore turbine-foundation structure as the prototype, the horizontal cyclic loading model tests of the wind power pile foundation with the scale of 1:50 were carried out. Considering the factors such as loading frequency and cyclic load ratio, the horizontal dynamic characteristics of the whole OWE pile foundation are studied. The comparison results between the maximum bending moment of pile and the fitting formula are discussed. In conclusion, moment of OWE pile shaft is corresponding to the loading frequency (f = 9 HZ) and loading cycles by fitting formulas. The fatigue damage of the OWE pile does not occurs with low frequencies in high cycles. [ABSTRACT FROM AUTHOR]

Soda residue (SR), a waste by-product of sodium carbonate production, occupies land resources and pollutes the environment seriously. To promote the resource reusing of waste SR, this paper studies the feasibility of utilizing SR for the preparation of soda residue soil (SRS) through laboratory and field tests. The SR and fly ash (FA) were mixed with six different proportions (SR:FA is 1:0, 10:1, 8:1, 6:1, 3:1, 1:1) to prepare SRS, and the optimum water content, maximum dry density, shear strength, and unconfined compression strength of the SRS were measured. The representative SRS (SR:FA is 10:1) was selected to investigate the compression performance and collapsibility. The preparation and filling method of SRS in the field was proposed, and the effects of gravel, sand, and lime on the mechanical properties of SRS were studied through field tests. The results show that the addition of FA contributed to the strength development of SR, and the addition of lime, sand and rubble have a significant effect on the subgrade bearing capacity of SRS. The subgrade bearing capacity and deformation modulus of SRS in field tests is more than 210 kPa and 34.48 MPa, respectively. The results provide experimental basis and reference for the preparation of SRS, the scientific application of SRS in geotechnical engineering to promote sustainable development. [ABSTRACT FROM AUTHOR]

When the open-ended pile penetrates the soil layer, the resistance generated by the soil plug cannot be ignored. A pile with a full-size pressure sensor installed at pile tip can detect resistance more accurately than a microsensor when the pile penetrates into the soil. In this paper, the pile installed full-size pressure sensor was used for penetration test and the relationship between formation parameters and pile tip force is obtained. Using the solution of the Kelvin problem in infinite space and the plane stress distribution function, the analytical solution of the bearing capacity of the soil plug is derived under the condition that the displacements of the bottom of the pile and the soil plug are consistent. The results show that the ultimate stress of the soil plug is closely related to the pile diameter and pipe thickness. The bearing capacity of the soil plug is closely related to the properties of the soil layer. The analytical solution of the bearing capacity of the soil plug has a linear relationship with the formation parameters SPT and CPT. The analytical solution of the ultimate bearing capacity of the soil plug has been verified by field test data and has a good match with the geometric dimensions of the pile tip and the formation parameters. [ABSTRACT FROM AUTHOR]

In order to have a better understanding of the real contact area of granular materials, the white light interference method is applied to explore the real surface morphology of clay soils under high stress. Analysis of the surface profile indicates that there exists a support point height z0 with the highest distribution frequency. A concept of a real contact region (from z0 to z0 + d90; d90 represents the particle size corresponding to 90% of the volume fraction) is proposed by combining a surface profile with the particle size distribution of clay soil. It was found that under the compressive stress of 106 MPa–529 MPa, the actual contact area ratio of clay soil varies between 0.375 and 0.431. This demonstrates an increasing trend with the rise of stress. On the contrary, the apparent porosity decreases with an increasing stress, varying between 0.554 and 0.525. In addition, as the compressive stress increases, the cumulative frequency of apparent profile height (from z0 − d90 to z0 + d90) has a concentrated tendency with a limited value of 0.9. [ABSTRACT FROM AUTHOR]

Biochar has been recently investigated as an eco-friendly material in bio-engineered slopes/landfill covers. A majority of recent studies have focused on analyzing water retention behavior while very few have examined dynamic behavior (i.e., cyclic loading due to earthquake, wind, or wave) of biochar amended soil. As far as the authors are aware, there is no study on the dynamic behavior of biochar amended soils. Considering the above mentioned study as a major objective, field excavated soil was collected and mixed with in-house produced biochar from peach endocarps, at three amendment rates (5%, 10%, and 15%). The un-amended bare soil and biochar amended soil were imposed to a cyclic load in a self-designed apparatus and the corresponding stress-strain parameters were measured. Dynamic parameters such as shear modulus and damping ratio were computed and the results were compared between bare and biochar amended soil. Furthermore, the residual cyclic strength of each soil types were correlated with an estimated void ratio to understand the interrelation between dynamic loading responses and biochar amended soils. The major outcomes of this study show that the addition of biochar decreases the void ratio, thereby increasing the shear modulus and residual cyclic strength. However, the modulus and strength values attenuates after 15 cycles due to an increase in pore water pressure. In contrary, at higher amendment rates, Biochar Amended Soils (BAS) forms clay-carbon complex and decreases both shear modulus and residual cyclic strength. [ABSTRACT FROM AUTHOR]

The coast–ship bistatic high-frequency surface wave radar (HFSWR) not only has the anti-interference advantages of the coast-based bistatic HFSWR, but also has the advantages of maneuverability and an extended detection area of the shipborne HFSWR. In this paper, theoretical formulas were derived for the coast–ship bistatic radar, including the first-order sea clutter scattering cross-section and the Doppler frequency shift of moving targets. Then, simulation results of the first-order sea clutter spectrum under different operating conditions were given, and the range of broadening of the first-order sea clutter spectrum and its influence on target detection were investigated. The simulation results show the broadening ranges of the right sea clutter spectrum and left sea clutter spectrum were symmetric when the shipborne platform was anchored, whereas they were asymmetric when the shipborne platform was underway. This asymmetry is primarily a function of platform velocity and radar frequency. Based on experimental data of the coast–ship bistatic HFSWR conducted in 2019, the broadening range of the sea clutter and the target frequency shift were analyzed and compared with simulation results based on the same parameter configuration. The agreement of the measured results with the simulation results verifies the theoretical formulas. [ABSTRACT FROM AUTHOR]

We introduce a class consisting of what we call quasi-periodic limit functions and then establish the relation between quasi-periodic limit functions and asymptotically quasi-periodic functions. At last, these quasi-periodic limit functions are applied to study the existence of asymptotically quasi-periodic solutions of abstract Cauchy problems. [ABSTRACT FROM AUTHOR]

Preservation of green infrastructure (GI) needs continuous monitoring of soil moisture. Moisture content in soil is generally interpreted on the basis electrical conductivity (EC), soil temperature and relative humidity (RH). However, validity of previous approaches to interpret moisture content in urban landscape was rarely investigated. There is a need to relate the moisture content with other parameters (EC, temperature and RH) to economize the sensor installation. This study aims to quantify the dynamics of the above-mentioned parameters in an urban green space, and to further develop correlations between moisture content and other parameters (EC, temperature and RH). An integrated field monitoring and statistical modelling approach were adopted to achieve the objective. Four distinct sites comprising treed (younger and mature tree), grassed and bare soil were selected for investigation. Field monitoring was conducted for two months to measure four parameters. This was followed by statistical modelling by artificial neural networks (ANN). Correlations were developed for estimating soil moisture as a function of other parameters for the selected sites. Irrespective of the type of site, EC was found to be the most significant parameter affecting soil moisture, followed by RH and soil temperature. This correlation with EC is found to be stronger in vegetated soil as compared to that without vegetation. The correlations of soil temperature with water content do not have a conclusive trend. A considerable increase in temperature was not found due to the subsequent drying of soil after rainfall. A normal distribution function was found from the uncertainty analysis of soil moisture in the case of treed soil, whereas soil moisture was observed to follow a skewed distribution in the bare and grassed soils. [ABSTRACT FROM AUTHOR]

Open-ended pipe piles have been increasingly used as the foundations for offshore structures. Considering the soil plugging effect, a novel analytical model is proposed in this paper to study the load transfer mechanism of open-ended pipe piles. A trilinear model for the external shaft friction was introduced, while a rigid plastic model was adopted to describe the load transfer at the pile-plug interface. Furthermore, an equilibrium equation of the soil plug was proposed, based on the hypothesis of a trilinear distribution of lateral earth pressure. The pile end resistance was analyzed by dividing it into two parts, i.e., the soil plug and pile annulus, the behaviors of which were described by the double broken line model. A calculation example was carried out to analyze the load transfer properties of the open-ended pipe piles. As a validation, similar load transfer processes of the open-ended pile were also captured in a newly built discrete element method model, mimicking the 100g centrifuge testing conditions. [ABSTRACT FROM AUTHOR]

Foundations for offshore wind turbines (OWTs) are mainly open-ended piles that are subjected to cyclic loadings caused by winds, waves and currents. This study aims to investigate the dynamic responses of open-ended pipe pile under lateral cyclic loadings, as well as the characteristics of the soil plug and surrounding soil. Both large-scale indoor model test and discrete element simulation were adopted in this study. The test results show that the resistance of each part of the pipe pile increases linearly with depth during the process of pile driving. The pile side resistance degradation effect was also observed along with the friction fatigue. The soil plug formation rate decreases gradually with an increase in the pile depth. The influence range in the surrounding soil is about 5~6 times of the pile diameter. The cumulative displacement of the pile head increases with the number of cycles. Lateral tangential stiffness and lateral ultimate bearing capacity decreases with an increase in number of cycles. The severe disturbance range of soil around the pile is 2~3 times of the pile diameter. The center of rotation of the pile body is about 0.8 times of the pile body depth. The side frictional resistance and lateral pressure of the pile body is found to fluctuate along the pile body. Additionally, the lateral pressure and side friction resistance decreases gradually with decreasing tendency of the former more than the latter. [ABSTRACT FROM AUTHOR]

The structure, valence state, and dielectric properties of (Ba1−xSmx)(Ti0.99Mn0.01)O3 (BSTM) (x = 0.02‒0.07) ceramics prepared via a high temperature (1400 °C/12 h) solid state reaction were investigated. A homogeneous and dense microstructure was observed in all samples. With increasing Sm content, the crystal structure changed from tetragonal (x ≤ 0.06) to cubic (x = 0.07) and unit cell volume (V0) decreased continuously, which was mainly due to the substitution of Ba2+ ions by smaller Sm3+ ions in the perovskite lattice. Electron paramagnetic resonance investigation revealed that Mn ions were reduced from high valence to low valence under the role of Sm3+ donor, and only Mn2+ ions were observed at x = 0.07. The Curie temperature (Tc) moved to lower values, from 105.5 down to 20.4 °C, and the x = 0.07 sample satisfied Y5V specification with high permittivity (ε′RT > 13,000) and low loss (tan δ < 0.03). [ABSTRACT FROM AUTHOR]

The (Ba0.96Nd0.04)Ti0.99O3 (BN4T) and (Ba0.96Nd0.04)(Ti0.94Ce0.05)O3 (BN4TC5) ceramics were prepared via the mixed oxide route exhibited tetragonal and pseudo-cubic structures, respectively. After they were preserved over a long period of time, a broader electron spin resonance (ESR) signal at g = 2.338 and a narrow ESR signal at g = 2.151 were detected at room temperature (RT) for BN4T and BN4TC5, respectively. They most likely originated from the Nd3+ Kramers ions in BN4T and Nd3+-Ce4+ defect complexes in BN4TC5 ceramics, respectively. The origins of these two ESR signals and the aging-resistant dielectric behavior are further discussed. [ABSTRACT FROM AUTHOR]

The (Ba 0.96 Nd 0.04 )Ti 0.99 O₃ (BN4T) and (Ba 0.96 Nd 0.04 )(Ti 0.94 Ce 0.05 )O₃ (BN4TC5) ceramics were prepared via the mixed oxide route exhibited tetragonal and pseudo-cubic structures, respectively. After they were preserved over a long period of time, a broader electron spin resonance (ESR) signal at g = 2.338 and a narrow ESR signal at g = 2.151 were detected at room temperature (RT) for BN4T and BN4TC5, respectively. They most likely originated from the Nd 3+ Kramers ions in BN4T and Nd 3+ -Ce 4+ defect complexes in BN4TC5 ceramics, respectively. The origins of these two ESR signals and the aging-resistant dielectric behavior are further discussed.