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In the current scenario of increasing energy scarcity and stricter environmental protection requirements, the utilization of coal gangue and biomass energy is gaining attention worldwide. Biomass and coal gangue are complementary in nature, and their co-combustion can improve the burnout efficiency of coal gangue and reduce pollutant emissions. In this study, coal gangue and wheat straw are selected as research subjects, the optimal process conditions for their co-combustion under the coupling of multiple parameters in oxy-fuel atmosphere through orthogonal experiments are investigated. The results indicate that the most significant factor influencing combustion characteristics is the heating rate. When the biomass content is 45 %, O2concentration is 50 %, heating rate is 30℃/min and particle size is 180–250μm, the flammability and comprehensive combustion indexes of the samples are maximized, which indicates the optimum combustion characteristics. The primary factor affecting pollutant release is biomass content. When the biomass content is 45 %, O2concentration is 75 %, combustion temperature is 700℃, and particle size is 180–250μm, the pollutant release concentration is minimized.

This study investigates the enhancement of peel-off resistance in polysulfone (PSU) membranes through the incorporation of bisphenol-A. The modified membranes were fabricated and characterized to evaluate their performance compared to conventional PSU membranes. Enhancing the interlayer adhesion within the composite membrane stands as a pivotal factor for ensuring its stable operation. Through meticulous characterization of the PSU structure and surface properties, our findings underscore the significant enhancement in interlayer adhesion facilitated by the introduction of bisphenol-A. In addition, we demonstrate the synergistic effects of PVP and SPSF additives in enhancing the hydrophilic nature of PSU membranes and the development of a novel active layer for membranes by incorporating 1.5 wt% polyvinyl alcohol with P(SS-MA) crosslinker on a PSU supporting layer. The synergistic effects of PVA and P(SS-MA) crosslinker contribute to improved salt rejection while maintaining structural integrity. Operating at a temperature of 70 ℃ and with a 3.5 wt% NaCl aqueous solution, the 16:1 membrane coated with a PVA/P(SS-MA) coating layer exhibited a remarkable flux of 53.6 ± 9.8 kg m−2h−1. Moreover, treating a highly concentrated solution of 10 wt% at the same temperature yielded a high flux of 38.73 ± 7.4 kg m−2h−1. Our findings underscore the potential of bisphenol-A modified PSU membranes as promising candidates for applications where strong adhesion and durability are paramount.

Quadrant detector (QD) is a widely adopted position sensor. By adopting ghost imaging, the four-channel outputs of the detector can be multiplexed to position and image the target simultaneously. However, the lens defocus and detector blind area distort the detected laser intensities, which would increase positioning error and reduce reconstruction image quality. In this research, the detection model is set up and analyzed based on the light spot distribution and detector characteristics. A neural network (NN)-based fitting method is proposed to directly predict spot position and correct total light intensities with detector outputs. The network is constructed and trained with simulation data. The prediction accuracy and generalization performance are verified by numerical simulations. The effectiveness of the proposed method is demonstrated in the experimental system. The positioning error of the proposed method decreases by 98.0% compared to the classic algorithm, and the signal-to-noise ratio of the reconstructed image increases by 31.94 dB. The proposed scheme has the potential to improve positioning accuracy and imaging quality of QD-based detection systems, such as radar and guidance applications.

Microplastics (MPs) can be sheltered by bed grains, resulting in a higher threshold of mobilization compared with those moving on a smooth bed. Only one formula considering the sheltering effects has been proposed for the critical shear stress (τc) of MP mobilization by including the densities and sizes of MPs and bed grains, but it is inaccurate for MPs of certain materials such as PS and shows limitations in understanding the sheltering effects. Additionally, no method exists for the critical depth-averaged velocity (Uc). In this study, experiments were conducted measuring both τcand Ucof MPs (made of PA, PVC, and PET) deposited on rough beds of different roughnesses, with a focus on the sheltering effects. A power law relationship between τcand the density and size of MPs was found, and a new formula for estimating τcwas proposed for MPs, which reduced the errors by approximately 40% compared with that of the previous formula (27.8%). To explicitly quantify the sheltering effects in MP mobilizations, hiddenness (ΔZ), exposure (ΔH), and longitudinal exposure (ΔX) were introduced, all of which were observed to follow a normal distribution. A semiempirical method for Ucwas then proposed incorporating the new measures, which reduced the errors by around 70% compared to the methods developed for estimating the Ucvalues of sediments.

• Potentials of LPSO phase and SFs are measured at micron and nanoscale in the same alloy. • Quasi in-situ AFM provides evidence for the effect of galvanic corrosion on film formation. • The overall potential fluctuation has an important effect on the corrosion resistance of Mg alloys. • It provides support for improving the corrosion resistance of high-strength Mg alloys. It is a long-term challenge to further improve the corrosion resistance while ensuring the strength of magnesium (Mg) alloys. Revealing the effect of potential fluctuation on the micro-galvanic corrosion and the subsequent film formation is important for understanding the corrosion mechanism of Mg alloys with multiple strengthening phases/structures. Here, we prepared the high-strength Mg-14.4Er-1.44Zn-0.3Zr (wt.%) alloys containing hybrid structures, i.e., elongated long-period stacking ordered (LPSO) blocks + intragranular stacking faults (SFs)/LPSO lamellae. The Mg alloy with elongated LPSO blocks and intragranular LPSO lamellae (EZ-500 alloy) obtains good corrosion resistance (2.2 mm y–1), while the Mg alloy containing elongated LPSO blocks and intragranular SFs (EZ-400 alloy) shows a significantly higher corrosion rate (6.9 mm y–1). The results of scanning Kelvin probe force microscopy (SKPFM) show the elongated LPSO blocks act as cathode phase (87 mV in EZ-400 alloy), and the SFs serve as the weak anode (30 mV in EZ-400 alloy), resulting in high potential fluctuation in EZ-400 alloy. On the contrary, both elongated blocks and intragranular lamellae are cathodic LPSO phase (67–69 mV) in EZ-500 alloy, leading to a lower potential fluctuation. Quasi in-situ atomic force microscope (AFM) observation indicates that high potential fluctuation would cause strong micro-galvanic corrosion, and subsequently leads to the failure in rapid formation of corrosion film, finally forming a loose and porous film, while relatively low potential fluctuation could result in more uniform corrosion mode and facilitate the rapid formation of protective film. Therefore, we propose that it is an effective way to develop high-strength corrosion-resistant Mg alloys by controlling the potential fluctuation to form a "uniform potential" strengthening microstructure. [ABSTRACT FROM AUTHOR]

In this study, the Mg–4Y–1Gd–1Nd–xCa–1Zn–0.3Zr (x= 0 and 0.4 wt%) cast alloys with low rare earth concentration were prepared in different routes of heat treatments, and their microstructures and mechanical properties were investigated. The Mg–4Y–1Gd–1Nd–1Zn–0.4Ca–0.3Zr cast alloy with ultimate tensile strength (UTS) of 264 ± 7.8 MPa, tensile yield strength (TYS) of 153 ± 1.2 MPa and elongation to failure (EL) of 17.2 ± 1.2% was successfully developed by appropriate heat treatment. The improved mechanical performance was attributed to the combined strengthening effects of fine grains, Mg24RE5, β′, β1, γ′and LPSO phases. In the heat treatment process, cooling method of T4 treatment affected the microstructure, which consequently determined the mechanical properties air cooling, rather than water cooling, gave rise to the formation of γ′phase in the alloy without Ca addition. However, Ca addition facilitated the formation of γ′phase, and the γ′phase precipitated in the alloy after T4 treatment either by water cooling or by air cooling, but the air cooling increased the number density of γ′phase in comparison to the water cooling. Although the γ′phase strengthened the studied alloys, the formation of γ′phase inhibited the precipitatition of β′and β1phases in the following T6 treatment, and consequently reduced the strengthening effect of β′and β1phases. The results showed that the mechanical performance of the studied alloys was largely determined by the precipitation of γ′phase, which was regulated by the Ca addition and the cooling method of T4 treatment.

In this study, we investigated the effects of single-stage ageing (SSA), two-stage ageing (TSA), 2% pre-strain + single-stage ageing (P2%SSA) and 2% pre-strain + two-stage ageing (P2%TSA) on the mechanical properties of as-extruded Mg–8Gd–3Y–0.5Ag–0.5Zr alloy (E alloy). Compared with the SSA treatment, the TSA treatment increased the number density of β′phase. The P2%SSA and P2%TSA treatments generated the γ′phase and chain-like precipitates in addition to the β′phase. The contributions of these ageing treatments to the alloy strengthening can be ranked as P2%TSA > P2%SSA > TSA > SSA, because the increments in the tensile yield strength were estimated to be 199 MPa > 148 MPa > 144 MPa > 110 MPa. Different from the traditional strengthening of β′phase in the E + SSA and E + TSA alloys, the composite precipitates comprising the β′phase, γ′phase and chain-like precipitates in the E + P2%SSA and E + P2%TSA alloys provided better combined strengthening effect. The β′phase was still dominated in the strengthening effect of the composite precipitates. Owing to the higher number density of β′phase in the composite precipitates, the E + P2%TSA alloy exhibited the better mechanical performance as compared with the E + P2%SSA alloy. Finally, the E + P2%TSA alloy had the ultimate tensile strength of 452 MPa, the tensile yield strength of 401 MPa and elongation to failure of 3.3%.

[Display omitted] • The TYS of the studied alloy is 295 MPa at 25℃ and 143 MPa at 200℃. • Theβ 1R phase is introduced in the studied alloy for the first time. • Theβ 1R phase forms by dislocation-assisted dynamic precipitation in hot extrusion. • Theβ 1R phase provides the alloy with a strong Orowan strengthening effect. In this work, a high-performance Mg-8.4Gd-4.4Li-3.5Y-1.4Zn (wt%) alloy was successfully prepared by low-temperature hot extrusion. The studied alloy has a TYS of 295 ± 1 MPa and an EL of 2.5 %±0.2 % at room temperature, 159 ± 8 MPa and 15.9 %±1.4 % at 150 °C, and 143 ± 4 MPa and 19.8 %±1.8 % at 200 °C. The high performance at temperatures up to 200 °C is attributed to the dispersion strengthening of three Mg 3 RE phase variants, the solid solution strengthening of alloying elements and the bimodal structure consisting of fine DRXed grains with random texture and coarse un-DRXed grains with basal texture. A novel island shaped β 1 R phase (FCC, a = 0.78 nm) with a size of 30 nm–100 nm is observed in the studied alloy. The β 1 R phase precipitates on the { 1 1 ¯ 00 } α prismatic planes. The strain-induced, dislocation-assisted dynamic precipitation during low-temperature hot extrusion is responsible for the formation of the β 1 R phase. The growth of the β 1 R phase is owing to the aid of the formation and transformation of zig-zag structures. The basal slip of < a > dislocations is the dominate deformation mechanism of the studied alloy in the early stage of tensile deformation at room temperature, while non-basal slip of < a > and < c + a > dislocations at 200 °C. Due to the strong interaction between β 1 R precipitates and dislocations, the densely distributed β 1 R precipitates significantly improve the mechanical properties via the Orowan strengthening both at room temperature and elevated temperatures. [ABSTRACT FROM AUTHOR]

This article applies flow drill screws (FDS) technology to the connection of dissimilar materials, carbon fiber-reinforced plastic (CFRP) and 6061-T6 aluminum alloy (AA6061-T6), and proposes a method to study the influence of FDS process parameters on the strength of the connection in stages. Based on this method, the optimal process parameters for the connection of this type of plate are explored. Firstly, the mathematical analysis of the process in each stage is conducted, and then the different process parameters in different stages are grouped and tested for the strength of the joint. The optimal process parameters obtained from the previous stage are input into the next stage for further testing, resulting in the highest shear connection strength of 5.98 kN for the FDS connection of CFRP and AA6061-T6 plates. The experimental results show that the influence of different process parameters on the strength of the joint varies in different stages. To improve the connection strength, high speed and low feed force should be selected in the second stage, low speed and low feed force should be selected in the third stage, and the tightening torque should be reasonably selected in the fourth stage.

An ancient hexaploidization event in the most but not all Asteraceae plants, may have been responsible for shaping the genomes of many horticultural, ornamental, and medicinal plants that promoting the prosperity of the largest angiosperm family on the earth. However, the duplication process of this hexaploidy, as well as the genomic and phenotypic diversity of extant Asteraceae plants caused by paleogenome reorganization, are still poorly understood. We analyzed 11 genomes from 10 genera in Asteraceae, and redated the Asteraceae common hexaploidization (ACH) event ~70.7–78.6 million years ago (Mya) and the Asteroideae specific tetraploidization (AST) event ~41.6–46.2 Mya. Moreover, we identified the genomic homologies generated from the ACH, AST and speciation events, and constructed a multiple genome alignment framework for Asteraceae. Subsequently, we revealed biased fractionations between the paleopolyploidization produced subgenomes, suggesting the ACH and AST both are allopolyplodization events. Interestingly, the paleochromosome reshuffling traces provided clear evidence for the two-step duplications of ACH event in Asteraceae. Furthermore, we reconstructed ancestral Asteraceae karyotype (AAK) that has 9 paleochromosomes, and revealed a highly flexible reshuffling of Asteraceae paleogenome. Of specific significance, we explored the genetic diversity of Heat Shock Transcription Factors (Hsfs) associated with recursive whole-genome polyploidizations, gene duplications, and paleogenome reshuffling, and revealed that the expansion of Hsfsgene families enable heat shock plasticity during the genome evolution of Asteraceae. Our study provides insights on polyploidy and paleogenome remodeling for the successful establishment of Asteraceae, and is helpful for further communication and exploration of the diversification of plant families and phenotypes.

The incipient motion threshold of microplastics (MPs), defined as the condition that is just sufficient to initiate MP movement, is key to assessing the transport and fate of MPs in water bodies, yet only a few studies have focused on its prediction. This study experimentally investigated the effects of bed roughness (smooth and rough beds) and MP properties (shapes, sizes, and densities) on the incipient velocity (Ui) and critical shear stress (τc) of exposed MPs in an open-channel flow. For a total of 19 types of MPs, Uiand τcwere found to range from 0.06 to 0.21 m/s and 0.01 to 0.075 N/m2, respectively. The commonly used thresholds for sediment transport, for example, critical shield parameter Θcand movability number Λc, were established for MPs based on τc. Based on the experimental data of the literature and this study, it was found that predictions of Θcand Λcfor sediments do not apply to MPs. A new explicit formula for Λcwas proposed for predicting the incipient motion of MPs by introducing the dimensionless particle diameter (d*) and a new dimensionless parameter related to the particle size, density, and shape. The new formula has an absolute error of 12.3%, which is smaller than the existing formula for MPs (55.6%).

A highly sensitive trapezium-shaped groove photonic crystal fiber (TSG-PCF) sensor based on surface plasmon resonance (SPR) is proposed and investigated numerically in low refractive index (RI) detection range of 1.181.30 by the finite element method (FEM). The trapezoidal groove is introduced, this sensor is simple in structure and manufactured easily. Indium tin oxide (ITO) is set as the sensing layer for the reaction between the core and the plasma. The influences of the structural parameters such as the holes parameters, the geometric parameters of the trapezium-shaped groove, the ITO layer thickness and other performance parameters on the design and sensing features of the proposed sensor are discussed comprehensively. The results show that for the proposed TSG-PCF, the maximum wavelength and amplitude sensitivities can arrive at 9100 nm/RIU and 99 RIU−1, the corresponding resolutions are 1.10 × 10−5RIU and 1.01 × 10−4RIU respectively in the analyte RI from 1.18 to 1.30. Moreover, the average sensitivity of 3429 nm/RIU can be realized for the appropriate parameters. The highly sensitive sensor makes the wide potential development for low RI detection in biological and chemical sensing.

A spider web-shaped terahertz photonic crystal fiber (PCF) is proposed. The transmission characteristics of the proposed PCF in the terahertz band areinvestigated based on the finite element method (FEM) by adjusting and optimizing the fiber structure parameters. The influences of the frequency, the core diameter, and the porosity on the transmission characteristics are deeply analyzed. Extremely low transmission losses can be achieved within the single mode transmission range of 0.6–1.2 THz, including the effective material loss (0.058 cm−1), the confinement loss (3.22 × 10-6dB/cm), and the bending loss (9.73 × 10-11cm−1).Additionally, the flat dispersion is as low as 0.075 ± 0.016 ps/THz/cm. At the same time, the fabrication technology of the proposed PCF is studied more thoroughly and systematically. This research can be suitable for long distance and high performance transmission of terahertz waves duo to its ultra low loss and flat dispersion.