Study on the corrosion behavior and mechanical response of weakly cemented sandstone in alkaline solutions.

This study examines the corrosion characteristics of weakly cemented sandstone under alkaline conditions, evaluating the effects of varying pH levels on its macroscopic degradation, micro-porosity, and mechanical properties, notably uniaxial compressive strength. Findings reveal that heightened alkalinity exacerbates rock damage, although a temporary alleviation in mass loss occurs between pH 9 and 11 due to pore clogging by complexes formed from cations like Ca2+ and Mg2+.Increased alkalinity induces marked changes in pore features, with an observed rise in pore numbers, transformation of pore shapes from elongated to more spherical, and adjustments in porosity, pore size, and roundness.

Study on key grouting blocking parameters of gas drainage boreholes in soft coal seams.

The construction of gas extraction boreholes in soft coal seams is prone to collapse and deformation, and grouting reinforcement is one of the main methods to solve the problem of efficient sealing. However, the reasonable selection of key grouting parameters still needs further research. In response to the problem of selecting grouting sealing parameters for gas drainage drilling in soft coal seams, based on the "concentric ring" reinforcement sealing technology obtained in previous research, the key parameters and sealing technology of the "concentric ring" reinforcement were studied through theoretical calculation and numerical simulation experiments.

Helicobacter hepaticus promotes liver fibrosis through oxidative stress induced by hydrogenase in BALB/c mice.

Background: It has been documented that Helicobacter hepaticus produces a nickel-containing hydrogen-oxidizing hydrogenase enzyme, which is necessary for hydrogen-supported amino acid uptake. Although H. hepaticus infection has been shown to promote liver inflammation and fibrosis in BALB/c mice, the impact of hydrogenase on the progression of liver fibrosis induced by H.

Study on Multifield Migration and Evolution Law of the Oxidation Heating Process of Coal Spontaneous Combustion in Dynamic Goaf.

To study the dynamic evolution law of the oxidation heating process of coal spontaneous combustion in the goaf during the advancing process of the working face, a dynamic model of oxidation heating of coal spontaneous combustion in the goaf was established on the basis of deformed geometry. Through numerical simulation research, the evolution and migration laws of seepage field, oxygen concentration field, temperature field, and high-temperature area of coal spontaneous combustion in the goaf during the advancement of the working face was obtained. The results indicate that the distribution of the bulking coefficient, porosity, and permeability of the falling coal and rock mass in the goaf is nonuniform.

Research and Application of "Concentric Ring" Reinforcement and Sealing Technology for Gas Drainage Boreholes in Soft-Coal Seams.

The problems of lack of stability and difficult sealing of gas drainage boreholes in soft-coal seams directly affect the efficient extraction of gas in these soft-coal seams. After the holes are drilled, the collapsed holes lead to the failure to seal in time, which brings hidden dangers to mine production and causes time and economic waste. In this paper, the viscoelastic mechanics model is used to solve the force of the coal body in the fractured area of the orifice, combined with the theory of the external conditions affecting the collapse of the orifice of the soft-coal seam.

Research on permeable pores in collapse column fillings with different gradation structures.

Particle loss is an important cause of water inrush catastrophes in collapsed columns. In order to study the relationship between the lost particles of different graded rock samples and the pore structure of the subsidence column filling, experiments were designed and the changes of the seepage parameters of graded rock samples during the particle migration process under different permeable water pressures P and axial loads F were determined. The results show that: (1) There will be obvious collapse, silting and particle loss behaviors in the sample during different loading processes, and the rock samples with gradation values of n = 0.

Experimental and Theoretical Study of the Time-Effect-Based Instability Characteristics of the Gas Drainage Borehole Sealing Section in a Soft Coal Seam.

The instability and sealing difficulty confronted by gas drainage boreholes in a soft coal seam weakens the drainage efficiency. To address this problem, the instability characteristics of the sealing section of boreholes are investigated. On the basis of the findings of the mechanical properties of the borehole around the sealing section and in view of the physical and mechanical properties of the soft coal seam, a theoretical analysis was performed.

Randall-sundrum brane model with 7D anti-de sitter space.

In the same sense that 5D anti-de Sitter space (AdS(5)) warped geometries arise naturally from type IIB string theory with stacks of D3 branes, AdS(7) warped geometries arise naturally from M theory with stacks of M5 branes. We compactify two spatial dimensions of AdS(7) to get AdS(5) x Sigma(2), where the metric for Sigma(2) inherits the same warp factor as appears in the AdS(5). We analyze the 5D spectrum in detail for the case of a bulk scalar or a graviton in AdS(5) x T(2), in a setup which mimics the first Randall-Sundrum model.