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Abstract An improved electroosmotic method is proposed in this paper to enhance the non-uniform effect and efficiency of electroosmotic process. Such method is electroosmotic flow with injection of calcium chloride through the anode, followed by injection through the central tube (a tube at the midpoint between the anode and the cathode) with a suitable time interval between injections. Experimental results indicate that using this method can significantly improve the non-uniform reduction in water content throughout the soil, mitigate the formation of cracks in the anode section, and therefore considerably inhibit the increase in the electric resistance. After treatment, the drained water could be raised to 3.59 times more than that of pure electroosmotic flow, and 1.3 times that of simultaneous injection through both the anode and the central tube with considerably slight increase in power consumption. Moreover, the area of cementation was also expanded, approximately twice larger than that of pure electroosmotic flow and one and a half that of simultaneous injection. It is also worth noting that the proposed method performs better with the same power consumption. The results demonstrate that electroosmotic flow with a suitable time interval between injections could improve the efficiency of electroosmotic process and expand the treatment region in soils, hence can be a promising and economic technique for soil improvement in practical engineering.

This research develops an elastoplastic damage constitutive model incorporating the strain softening response of common engineering soil materials in southeastern Xizang to evaluate and optimize reinforcement solutions for highway-traversing landslide accumulations. Grounded in deterioration mechanics theory, the model characterizes the progressive strength loss and failure evolution of the soils. Verified and calibrated, it is numerically implemented in FLAC3D to simulate the stability conditions of a landslide affecting planned highway infrastructure in southeastern Xizang. Safety factors of 1.25, 1.07, and 1.02 under normal operation, rainfall, and seismic excitation loads, respectively, reveal the inadequacy of intrinsic stability. Consequently, dynamic compaction and chemical grouting techniques are assessed via simulation. An optimal strategy, entailing 6-m-deep densification at the highway location with 10% silica fume enhancement of 66.3% of the landslide area and 50.8% of the soil-bedrock interface, results in safety factors of 1.70, 1.49, and 1.23 for the three scenarios. The improved area is minimized to streamline construction practicality and economics while preserving geotechnical integrity. The integrated modeling outcomes demonstrate the model's capability in capturing localized incremental damage and the efficacy of numerical simulation for stability diagnosis and targeted remediation of intricate landslides. Advancements in constitutive relations development are vital for further innovation in geohazard evaluation and infrastructure safety assurance.

The bulk photovoltaic effect (BPVE) in layered materials has garnered widespread attention due to its large shift current responses and promising potential for efficient photoelectric energy conversion. Here, we systematically investigate the shift current responses of BPVE in layered β-ZrI2 and bilayer ZrI2, demonstrating that large shift current of out-of-plane of 110 μA/V2 and 55 μA/V2 are achieved in β-ZrI2 and bilayer ZrI2 respectively, under ambient conditions. Intriguingly, the shift current of β-ZrI2 and bilayer ZrI2 demonstrates further improvement under the regulation of external stimuli. Especially, the σzxx component of shift current tensor in β-ZrI2 increases from 29 μA/V2 to 51 μA/V2 upon compression up to 3 GPa, while the largest shift current of bilayer ZrI2 reaching 170 μA/V2 under tensile strain. The notable enhancement of shift current responses in β-ZrI2 and bilayer ZrI2 is closely associated with charge delocalization occurred around Zr atoms and strain-enhanced joint density of states (JDOS), respectively. These findings provide the visionary insights for exploring and developing high-performance BPVE materials.

Abstract Increasing the charging cut‐off voltage (e.g., 4.6 V) to extract more Li ions are pushing the LiCoO2 (LCO) cathode to achieve a higher energy density. However, an inhomogeneous cycled bulk‐to‐surface Li distribution, which is closely associated with the enhanced extracted Li ions, is usually ignored, and severely restricts the design of long lifespan high voltage LCO. Here, a strategy by constructing an artificial solid–solid Li diffusion environment on LCO's surface is proposed to achieve a homogeneous bulk‐to‐surface Li distribution upon cycling. The diffusion optimized LCO not only shows a highly reversible capacity of 212 mA h g−1 but also an ultrahigh capacity retention of 80% over 600 cycles at 4.6 V. Combined in situ X‐ray diffraction measurements and stress‐evolution simulation analysis, it is revealed that the superior 4.6 V long‐cycled stability is ascribed to a reduced structure stress leaded by the homogeneous bulk‐to‐surface Li diffusion. This work broadens approaches for the design of highly stable layered oxide cathodes with low ion‐storage structure stress.

Abstract This paper presents a cement-content controlled method for quality assessment and quality control of the deep soil mixing (DSM) columns in slope reinforcement. The ethylene diamine tetraacetic acid (EDTA) titration method was modified and used for the cement content measurement of core samples, and the effects of curing conditions and curing period on the titration results were investigated. 35 DSM columns with different construction parameters were installed in the test section, and cement content and unconfined compression tests of field core samples were conducted. The relationship between the unconfined compressive strength (UCS) and cement content of DSM columns was formulated, and the quality of DSM columns with different construction parameters was assessed. The test results suggested that the failure strength of the field cores was approximately 15–55% lower than that of laboratory samples with the same cement content. In single columns, the coefficient of variation (CV) of cement content had a negative correlation with the average failure strength and a positive correlation with the coefficient of variation of failure strength. Bidirectional mixing method, lower penetration and withdrawal velocity, more mixing blades and larger number of mixings could improve the uniformity of the DSM columns.

In order to meet people’s demand for strawberry during winter and early spring, strawberry is usually cultivated in solar greenhouses with forcing cultivation in northern China. However, low light intensities and short-days are the major obstacles that restrict strawberry growth. Therefore, it is crucial to solve the problem of insufficient light in strawberry production. In this study, we established LED facilities to supplement the red/blue light (R/B = 4:1) before sunrise and after sunset in the solar greenhouse. We found that the plant height of the strawberry under supplemental R/B light was 13%−17% higher than that of the control, and the crown diameter of the plants was increased by 1.07−1.38 fold compared with the control for two consecutive years. The net photosynthetic rate of strawberry plants was 19% higher than that of the control. In addition, the strawberry primary fruits’ fresh weight during the stage of full ripeness and the total fruit weight/plant was 18%−24% and 27%−33% higher than that of control for two years, respectively. Fruit soluble solid content and firmness were increased by 1.05−1.21 fold and 1.06−1.18 fold compared with those of control during the two years, respectively. Moreover, we found some differentially expressed genes between red/blue light supplementation and control by RNA-seq, including light-responsive genes (PRR95/LHY/CDF3/CO16/bHLH63/BBX21/PAR1/SIGE) and sucrose metabolism-related genes (SWEET9/BAM1). This study provided a foundation for revealing the mechanism of red/blue light supplementation on photosynthesis and fruit quality of strawberries and could help to improve the cultivation techniques for 'Yanli' strawberry.

Thorium monocarbide (ThC) is interesting as an alternative fertile material to be used in nuclear breeder systems and thorium molten salt reactors because of its high thermal conductivity, good irradiation performance, and wide homogeneous composition range. Here, the influence of carbon vacancy site and concentration on lattice distortions in non-stoichiometric ThC1−x (x = 0, 0.03125, 0.0625, 0.125, 0.1875, 0.25, or 0.3125) is systematically investigated using first-principle calculations by the projector augmented wave (PAW) method. The energy, mechanical parameters, and thermodynamic properties of the ThC1-x system are calculated. The results show that vacancy disordering has little influence on the total energy of the system at a constant carbon vacancy concentration using the random substitution method. As the concentration of carbon vacancies increases, significant lattice distortion occurs, leading to poor structural stability in ThC1−x systems. The changes in lattice constant and volume indicate that ThC0.75 and ThC0.96875 represent the boundaries between two-phase and single-phase regions, which is consistent with our experiments. Furthermore, the structural phase of ThC1−x (x = 0.25–0.3125) transforms from a cubic to a tetragonal structure due to its ‘over-deficient’ composition. In addition, the elastic moduli, Poisson’s ratio, Zener anisotropic factor, and Debye temperature of ThC1-x approximately exhibit a linear downward trend as x increases. The thermal expansion coefficient of ThC1−x (x = 0–0.3125) exhibits an obvious ‘size effect’ and follows the same trend at high temperatures, except for x = 0.03125. Heat capacity and Helmholtz free energy were also calculated using the Debye model; the results showed the C vacancy defect has the greatest influence on non-stoichiometric ThC1−x. Our results can serve as a theoretical basis for studying the radiation damage behavior of ThC and other thorium-based nuclear fuels in reactors.

At present, in the design of geotechnical structures, the allowable bearing capacity is mostly designed according to the safety factor specified in the design specification. However, there are two problems that have not yet been clearly explained in theory: (1) why is the safety factor listed in the standard is suitable for the design of geotechnical structures and (2) can the safety factor selected according to the specification guarantee the long-term stability of soil mass. In view of the above problems, according to the statistical law in the rheological properties of soil, the relationship between the shear stress level of the soil and the stability of the soil is studied, and the stable shear stress level of the soil is obtained. The research results show that the stable shear stress level of soil is the corresponding shear stress level under static earth pressure. This conclusion not only verifies the correctness of the theoretical finding that “the earth pressure on the structure develops toward the static earth pressure, and whether the ultimate safety of the geotechnical structure is related to its design bearing capacity is greater than the static earth pressure” in the design code of the retaining structure but also clarifies the source of the safety factor. By calculating the design bearing capacity of the geotechnical structure according to the static earth pressure, the geotechnical structure that maintains long-term stability can be designed, which provides a reliable method for the design of the permanent geotechnical structure.

ObjectiveWe performed a meta-analysis to investigate the relationship between blood tumor necrosis factor-alpha (TNF-α) levels and the risk of cerebral palsy (CP) in children.MethodsPubMed, Web of Science, Cochrane Library and Ovid databases were searched from the date of database inception to 26 April 2022. Data were extracted and pooled from observational studies related to TNF-α and the risk of CP in children. Quality was assessed using the Newcastle-Ottawa Scale. We used the inverse variance method with a random-effects model to estimate the odds ratios with 95% confidence intervals (CIs), and stratified analyses and sensitivity analysis were utilized to analyse heterogeneity.ResultsNine studies with 1,117 cases and 3,563 controls were included in our meta-analysis. The quality of the literature was good, and no publication bias was noted. According to the random-effects model, blood TNF-α levels were associated with the risk of CP (OR 1.82; 95% CI, 1.25–2.66) in a heterogeneous set of studies (I2 = 81.2%, p = 0.000).ConclusionOur findings indicate that elevated TNF-α levels in the blood are associated with an increased risk of CP. The association of TNF-α with CP requires further investigation.

Due to their magnetic and physical properties, rare earth magnetic borides have been applied to a variety of critical technologies. In particular, rare earth tetraborides are more abundant as frustrated antiferromagnets. Here, the atomic structures, magnetic structures, and electronic structures of NdB4 have been studied by first-principle calculations. The ground state magnetic structure of NdB4 is determined. Moreover, the small energy difference between different magnetic structures means that there may be more than one magnetic structure that coexist. One can glean from the electronic structure of the magnetic ground state that the d orbital of Nd is strongly hybridized with the p orbital of B, and the f electron of Nd is highly localized. The computational results reveal the complexity of the magnetic structure and provide a theoretical basis for studying the magnetic ground state of NdB4.

To obtain the applicable filter layer range of the silt sand around the dewatering well of a ship lock renovation project in Nanjing, several existing classic filter layer criteria are analyzed, and the concept of a progressively stable filter system is put forward accordingly. The self-designed horizontal percolation filter is used to carry out the silt filter test, and the filter effect of these graded filter materials on the test silt filter is studied, and the mechanism of the progressively stable filter system is described. Tests show that when the ratio of the filter material to the characteristic particle size of the silt soil falls within the range of 4.3–7.7, the system maintains a stable percolation state. Through the particle tests of the base soil and the filter material after filtering, it is found that an effective filter system is that the filter layer induces soil’s self-filtration, and they work together. No matter what filter material criterion is used to design the filter, as long as the gradual and stable filtration mechanism is formed in the filtration process, stable filtration can be ensured. The research on the progressively stable filter system will help to determine the gradation range of the filter material more reasonably in the engineering design, reduce the failure probability of the filter layer, and provide a certain reference for the design of the filter layer in similar projects in the future.

Introduction The aim of our study is to investigate the effect of hyperbilirubinaemia on synaptic plasticity in the dentate gyrus (DG) region of the rat hippocampus. Material and methods Seven-day-old healthy Sprague Dawley (SD) rats were randomly divided into a control group and an experiment group (n = 20 in each group). The input/output (I/O) functions, paired-pulse reactions (PPR), excitatory postsynaptic potential (EPSP), and population spike (PS) amplitude were measured in the DG area of both groups of rats in response to stimulation applied to the lateral perforant path. Results Compared with that in the control rats, the current-voltage curves of both EPSP slope and PS amplitude in the experimental rats were significantly depressed. The average peak facilitation was 187 ±16% in the control and 164 ±18% in the experiment group (F = 21.054, p < 0.01). The facilitation period duration of PS was 155 ms in the experimental rats, which was less than that of the controls (235 ms). In the control group, the long-term potentiation (LTP) amplitudes were 140 ±3.5% and 242 ±6%, when estimated from the EPSP slope and PS amplitude, respectively, which were significantly depressed to 124 ±3.4% (EPSP slope, F = 70.489, p < 0.01) and 138 ±8.6% (PS amplitude, F = 253.46, p < 0.01), respectively, in the experiment group. Conclusions These findings suggest that hyperbilirubinaemia could induce impairment of synaptic plasticity in the rat DG area in vivo, including I/O function, paired-pulse ratio (PPR), and LTP, which may be closely related to cognitive impairment.

To improve the stability of sand slopes in Southeast Tibet, the wet–dry cycle test, immersion test, and permeability test were carried out using polyvinyl alcohol (PVA) as the improving material. The improvement effect was evaluated by considering the unconfined compressive strength. The results have revealed that the unconfined compressive strength of the improved soil significantly increased with the PVA content, while the degradation of the improved soil by wet–dry cycling and water immersion weakened. However, the permeability of the improved soil slightly decreased compared with that of unmodified soil. Through scanning electron microscopy (SEM), it was found that PVA only forms an elastic network structure in the sand to wind and connect the soil particles, but pores remain in the sand. This indicates that the addition of PVA does not affect the permeability to a great extent but greatly increases the strength. The findings of this study provide a useful reference for the practical application of PVA.

Laboratory freezing experiments were conducted to evaluate the effect of polyacrylamide (PAM) and lignocellulose on the mechanical properties and microstructural characteristics of Tibetan clay. Direct shear and unconfined compressive tests and field emission scanning electron microscopy analyses were performed on clay samples with different contents of stabilizers. The test results show that the addition of PAM can improve the unconfined compressive strength and cohesion of Tibetan clay, but an excessive amount of PAM reduces the internal friction angle. After several freeze-thaw cycles, the unconfined compressive strength and cohesion of samples stabilized by PAM decrease significantly, while the internal friction angle increases. Samples stabilized by PAM and lignocellulose have higher internal friction angles, cohesion, and unconfined compressive strength and can retain about 80% of the original strength after 10 freeze-thaw cycles. PAM fills the pores between soil particles and provides adhesion. The addition of lignocellulose can form a network, restrict the expansion of pores caused by freeze-thaw cycles, and improve the integrity of PAM colloids. It is postulated that the addition of a composite stabilizer with a PAM content of 0.4% and a lignocellulose content of 2% may be a technically feasible method to increase the strength of Tibetan clay.

This paper proposes the use of calcium carbonate (CaCO3) precipitation induced by the addition of calcium chloride (CaCl2) and sodium carbonate (Na2CO3) solutions as a procedure to stabilize and improve expansive soil. A set of laboratory tests, including the free swell test, unloaded swelling ratio test, unconfined compression test, direct shear test, scanning electron microscopy (SEM) test, cyclic wetting–drying test and laboratory-scale precipitation model test, were performed under various curing periods to evaluate the performance of the CaCO3 stabilization. It is concluded from the free swell tests and unloaded swelling ratio tests that the addition of CaCl2 and Na2CO3 can profoundly decrease soil expansion potential. The reduction in expansion parameters is primarily attributed to the strong short-term reactions between clay and stabilizers. In addition, the formed cementation precipitation can decrease the water adsorption capacity of the clay surface and then consequently reduce the expansion potential. The results of unconfined compression tests and direct shear strength tests indicated that the addition of CaCl2 and Na2CO3 has a major effect on geotechnical behavior of expansive soils. Based on the SEM analyses, new cementing crystalline phases formatted by sequentially mixing CaCl2 and Na2CO3 solutions into expansive soil were found to appear in the pore space, which results in a much denser microstructure. A laboratory-scale model test was conducted, and results demonstrate the effectiveness of the CaCO3 precipitation technique in stabilizing the expansive soil procedure. The test results indicated that the concentration of CaCl2 higher than 22.0% and Na2CO3 higher than 21.2% are needed to satisfactorily stabilize expansive soil. It is proposed to implement the precipitation technique in the field by the sequential permeation of CaCl2 and Na2CO3 solutions into soils in situ.

LiNi1−x−yMnxCoyO2 materials are a typical class of layered cathode materials with excellent electrochemical performance in lithium-ion batteries. Molecular dynamics simulations are performed for LiNi1−x−yMnxCoyO2 materials with different transition metal ratios. The Li/Ni exchange ratio, ratio of anti-site Ni2+ to total Ni2+, and diffusion coefficient of Li ions in these materials are calculated. The results show that the Li-ion diffusion coefficient strongly depends on the ratio of anti-site Ni2+ to total Ni2+ because their variation tendencies are similar. In addition, the local coordination structure of the Li/Ni anti-site is analyzed.

Tunnel construction is susceptible to accidents such as loosening, deformation, collapse, and water inrush, especially under complex geological conditions like dense fault areas. These accidents can cause instability and damage to the tunnel. As a result, it is essential to conduct research on tunnel construction and grouting reinforcement technology in fault fracture zones to address these issues and ensure the safety of tunnel excavation projects. This study utilized the Xianglushan cross-fault tunnel to conduct a comprehensive analysis on the construction, support, and reinforcement of a tunnel crossing a fault fracture zone using the three-dimensional finite element numerical method. The study yielded the following research conclusions: The excavation conditions of the cross-fault tunnel array were analyzed to determine the optimal construction method for excavation while controlling deformation and stress in the surrounding rock. The middle partition method (CD method) was found to be the most suitable. Additionally, the effects of advanced reinforcement grouting on the cross-fault fracture zone tunnel were studied, and the optimal combination of grouting reinforcement range (140°) and grouting thickness (1m) was determined. The stress and deformation data obtained from on-site monitoring of the surrounding rock was slightly lower than the numerical simulation results. However, the change trend of both sets of data was found to be consistent. These research findings provide technical analysis and data support for the construction and design of cross-fault tunnels. [ABSTRACT FROM AUTHOR]

Introduction: The aim of our study is to investigate the effect of hyperbilirubinaemia on synaptic plasticity in the dentate gyrus (DG) region of the rat hippocampus.Material and Methods: Seven-day-old healthy Sprague Dawley (SD) rats were randomly divided into a control group and an experiment group (n = 20 in each group). The input/output (I/O) functions, paired-pulse reactions (PPR), excitatory postsynaptic potential (EPSP), and population spike (PS) amplitude were measured in the DG area of both groups of rats in response to stimulation applied to the lateral perforant path.Results: Compared with that in the control rats, the current-voltage curves of both EPSP slope and PS amplitude in the experimental rats were significantly depressed. The average peak facilitation was 187 ±16% in the control and 164 ±18% in the experiment group (F = 21.054, p < 0.01). The facilitation period duration of PS was 155 ms in the experimental rats, which was less than that of the controls (235 ms). In the control group, the long-term potentiation (LTP) amplitudes were 140 ±3.5% and 242 ±6%, when estimated from the EPSP slope and PS amplitude, respectively, which were significantly depressed to 124 ±3.4% (EPSP slope, F = 70.489, p < 0.01) and 138 ±8.6% (PS amplitude, F = 253.46, p < 0.01), respectively, in the experiment group.Conclusions: These findings suggest that hyperbilirubinaemia could induce impairment of synaptic plasticity in the rat DG area in vivo, including I/O function, paired-pulse ratio (PPR), and LTP, which may be closely related to cognitive impairment. [ABSTRACT FROM AUTHOR]

The environmental-friendly modified starch as filtrate reducers in water-based drilling fluids respectively were successfully synthesized and characterized in detail. The starch-based filtrate reducers (SFR) were firstly synthesized through etherification-crosslinking composite modification. The evaluation results indicate that SFR exhibits good thermal stability due to the introduction of strong hydration sulfonate groups and the formation of complex network structure in the molecular structure of modified starch. Furthermore, rheological and filtration measurements were performed to investigate its feasibility or compatibility of SFR as filtrate reducers for water-based drilling fluids. The results demonstrate that SFR has excellent filtration reduction properties, high temperature and salt resistance. The starch-based filtrate reducers (SFR) also presents favorable environmentally friendly performance with EC50 value of 96500mg/. The starch-based filtrate reducers (SFR) could be environmentally friendly and priority alternatives to conventional filtrate reducers in water-based drilling fluids. [ABSTRACT FROM AUTHOR]