Search

This study aims to characterize the pore structures and controlling factors of the Shan-1 Member reservoir in the southwestern Ordos Basin, a geological formation known for its significant gas production. Thin section analysis, scanning electron microscopy, high-pressure mercury intrusion (MICP), and reservoir physical property analysis were employed to investigate the pore structures within the reservoir. The Shan-1 Member reservoir is primarily characterized by lithic dissolution and intergranular pores, with generally small throat radii. Reservoirs with high quartz content (>70%) are associated with the development and preservation of primary pores, resulting in superior pore structures (Types I and II) with larger pore throats. Similarly, reservoirs with low lithic content (

Salivary hypofunction is a common complication in patients with head and neck cancers following radiotherapy (RT). RT‐induced inflammation in salivary gland cells leads to apoptosis and fibrosis. Artesunate (ART) is a bioactive compound with anti‐inflammatory and anti‐fibrosis properties. This study aimed to investigate the protective effects of ART on X‐ray‐induced injury of submandibular gland (SMG) epithelial cells in rats. Second‐generation SMG epithelial cells were randomly divided into five groups: natural control group (NC), irradiated group (IR), and irradiated groups treated with ART at concentrations of 5, 10, and 20 μM. Cells were harvested 48 h postirradiation for analysis. The results demonstrated that ART attenuated the damage to AQP5, a crucial indicator of salivary gland function, as evidenced by the decreased expression of AQP5 at both mRNA and protein levels. Additionally, ART decreased the expression of inflammatory cytokines: IL‐6 and TNF‐α. TUNEL staining revealed reduced apoptosis in the ART groups, particularly the IR + 10 μM group. RT‐PCR and Western blot analysis of apoptosis cytokines Bax/Bcl‐2 and Caspase‐3 confirmed these findings. Furthermore, ART inhibited the expression of NF‐κB at both mRNA and protein levels. In conclusion, these results suggest that ART may reduce inflammation and apoptosis in SMG epithelial cells following radiation by inhibiting the NF‐κB pathway. [ABSTRACT FROM AUTHOR]

Land subsidence, marked by a decline in surface elevation, poses a significant threat to urban infrastructure and safety. Accurate subsidence information and a reliable prediction model are crucial for prevention and control. In this study, we used persistent scatterer interferometric synthetic aperture radar (PSInSAR) technology to obtain long-term land subsidence data and analyzed subsidence characteristics in Decheng District. By integrating hydrogeological and groundwater data, we developed a three-dimensional groundwater flow and one-dimensional compaction model through numerical simulation. Furthermore, the subsidence data monitored by PS-InSAR were used to further constrain and validate the model. The evolution trend of land subsidence under different groundwater exploitation scenarios was predicted and analyzed. The results showed that from May 2017 to December 2021, the cumulative maximum subsidence in Decheng District reached -173 mm. The subsidence area is mainly concentrated in the northern area, and its subsidence center is near Qiaoyuan Town. According to the Land Subsidence Prevention and Control Plan of Dezhou City, Shandong Province (2018-2025), we set up different groundwater mining scenarios with the goal that the rate of land subsidence in the key prevention and control area is less than 35 mm/yr in 2025.The Fluidsolid coupled model prediction analysis results indicated that a 30% reduction in groundwater exploitation is reasonable. [ABSTRACT FROM AUTHOR]

Matrix effects are a major concern in liquid chromatography coupled to tandem mass spectrometry for the determination of pesticide residues. In this work, a novel and efficient lipophilicity-matched chromatographic separation strategy was developed to improve the separation efficiency on an alkyl bonded phase chromatographic column and reduce matrix effects. An ultra-high performance liquid chromatography-tandem mass spectrometry method based on this strategy was established to minimize matrix effects for the determination of triazole fungicides. The samples were cleaned-up with dispersive solid phase extraction and separated on a chromatographic column with similar lipophilicity to the fungicides. The results showed that the proposed method effectively minimized the matrix effects and improved the separation. The matrix effects of 21 fungicides ranged from −8.3% to 4.7%. Moreover, the average recoveries were between 91.4% and 108.1% using solvent calibration for quantification, and the limits of quantitation were between 0.5 and 3.5 μg/kg. These results demonstrate the effectiveness of the proposed strategy in improving the chromatographic efficiency. This work provides a practical strategy and reference for the liquid chromatography-tandem mass spectrometry determination of pesticide residues. [ABSTRACT FROM AUTHOR]

The reconstruction of the porous media model is crucial for researching the mesoscopic seepage characteristics of porous concrete. Based on a self-compiled MATLAB program, a porous concrete model was modeled by controlling four parameters (distribution probability, growth probability, probability density, and porosity) with clear physical meanings using a quartet structure generation set (QSGS) along with the lattice Boltzmann method (LBM) to investigate permeability. The rationality of the numerical model was verified through Poiseuille flow theory. The results showed that the QSGS model exhibited varied pore shapes and disordered distributions, resembling real porous concrete. Seepage velocity distribution showed higher values in larger pores, with flow rates reaching up to 0.012 lattice point velocity. The permeability–porosity relationship demonstrated high linearity (the Pearson correlation coefficient is 0.92), consistent with real porous concrete behavior. The integration of QSGS-LBM represents a novel approach, and the research results can provide new ideas and new means for subsequent research on the permeability of porous concrete or similar porous medium materials. [ABSTRACT FROM AUTHOR]

This paper conducts compressive strength tests on foam concrete prepared under four factors and three levels through the design of orthogonal experiments. It delves into the phase change rules of the load–displacement curves obtained under various mix proportions. Furthermore, based on the 1-day and 3-day compressive strength values, the study explores different mix proportion results using range analysis and variance analysis methods, thereby determining the optimal mix proportion that can satisfy the maximum 1-day and 3-day compressive strength values. The results indicate that the compression process of rapid-hardening foam concrete includes four stages: initial compaction stage, elastic stage, yielding stage, and plateau stage, with each stage having different causes. Additionally, the sensitivity sequence of factors affecting the 1-day and 3-day compressive strength of rapid-hardening foam concrete is respectively rapid sulfoaluminate cement (α) > water-reducing agent content (δ) > foam content (β) > water-cement ratio (γ) and rapid sulfoaluminate cement (α) > water-cement ratio (γ) > foam content (β) > water-reducing agent content (δ). With 100% sulfoaluminate cement content, the 1-day and 3-day compressive strength values can reach 1.7054 and 2.5471 MPa, respectively, which are 13 times and 7 times the minimum values of 1-day and 3-day compressive strength under other admixtures. The analysis shows that the content of rapid sulfoaluminate cement has the most significant effect on the 1-day and 3-day compressive strength of rapid-hardening foam concrete, with foam content having the least impact on 1-day compressive strength and water-reducing agent content having the least impact on 3-day compressive strength. By integrating range analysis and variance analysis, the optimal mix proportion that simultaneously satisfies the maximum 1-day and 3-day compressive strength is determined to be 100% content of rapid-hardening sulfoaluminate cement, 4% foam content, 0.55% cement ratio, and 0.12% admixture content. Overall, this study provides theoretical support for the research and development of new rapid-hardening foam concrete materials and has significant practical implications for the emergency repair and construction of infrastructure projects. [ABSTRACT FROM AUTHOR]

Land subsidence is an environmental geological phenomenon mainly caused by groundwater overexploitation. Long-term overexploitation of groundwater not only causes compaction of aquifer thickness and surface deformation but also leads to the loss of aquifer water storage capacity. The skeleton water storage coefficient (Sk) is an important parameter for evaluating the water storage capacity of aquifer groups. This article proposes a new research framework for obtaining the Sk of different aquifer groups: combining permanent scatter for SAR interferometry technology and a multiscale geographic weighted regression model to obtain subsidence information for different aquifer groups, inverting the Sk of different aquifer groups from the spatial scale, and discussing the deformation characteristics of soil layers under different water head change modes to evaluate the deformation and water storage characteristics of different aquifer groups. This framework is applied to the land subsidence region of the Beijing Plain. We calculated that the settlement proportions of different compression layer groups were 14.75%, 23.65%, 33.44%, and 28.16%. Due to the different lithological compositions and groundwater exploitation of different aquifers, the Sk values exhibit different spatial distribution characteristics. With the continuous development of subsidence, the water storage performance of the aquifer group is continuously declining. These findings contribute to managing the sustainable use of groundwater resources and controlling subsidence. It is demonstrated that the research framework proposed in this article can serve as an effective tool for obtaining settlement information and the Sk of different aquifer groups. [ABSTRACT FROM AUTHOR]