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The emission of greenhouse gases, especially carbon dioxide (CO2), is a major contributor to global climate change and the ecological environment. Geological storage of CO2in deep saline aquifers is currently a widely recognized method due to its stable storage and strong feasibility. The density of brine plays a crucial role in influencing the diffusion and migration of CO2in brine aquifers. It further affects the long-term stable storage of CO2in brine. In the existing brine reservoir models, the importance of density calculation is often overlooked. Therefore, the purpose of this study is to develop a long-term storage model with accurate density and evaluate the performance of the CO2storage potential. First, the electrolyte perturbed-channel statistical associating fluid theory (ePC-SAFT) equation of state was applied in phase equilibrium of the H2O–NaCl and CO2–H2O–NaCl systems. The results were validated against experimental data, demonstrating that ePC-SAFT can effectively describe the phase behavior of these two systems. The density of brine was then modified and incorporated into the numerical simulation model. Simulation results indicated that the stable CO2storage potential is underestimated by 7.6%. After that, various factors affecting the CO2storage efficiency were ranked based on different monitoring periods, including the reservoir temperature, residual gas saturation, horizontal permeability heterogeneity, ratio of vertical to horizontal permeability, and pH. The results indicate that different factors have varying degrees of influence on storage efficiency at different monitoring periods and mechanisms. At the end of 1000 years, the impact of residual gas saturation on the efficiency of stable trapping is particularly pronounced. This study provides a theoretical basis for assessing the potential for CO2storage in saline aquifers and selecting the optimal storage reservoirs.

Complex interaction between fluid and solid in tight formations leads to capillary confinement and interface slip. Mass transfer between oil and CO2in CO2flooding is essential to understand the flow complexity. Therefore, the objective of this work is to propose a comprehensive model to analyze the mass transfer during CO2injection in the confined fluids. The modified Peng-Robinson equation of state considering the fluid-wall interaction and adsorption was established to calculate the properties of hydrocarbons and CO2. Relative permeability for the near-miscible state was then estimated using the new relative permeability model with corner flow effect. Predicted results agree well with the experimental observations. Afterwards, it was integrated with a one-dimension mathematical model to analyze the physical mechanisms of CO2flooding in tight reservoirs. Results indicate that nanoconfinement increases the relative permeability at near-miscible condition, and confined fluid is more likely to be miscible than the bulk fluid. Additionally, nanoconfinement can reduce the velocity of CO2front and increase the breakthrough time of CO2, which is favorable to improve the efficiency of CO2flooding. This model provides a deep understanding of mass transfer between CO2and hydrocarbons, and it can be integrated with compositional simulators to solve the field-scale cases including the microscale mechanism of tight reservoirs.

To observe the effect and mechanism of Xiangsha Liujunzi decoction (XSLJZD) drug serum on gastric antrum smooth muscle cells (SMCs) in rats with functional dyspepsia (FD).

Hydraulic fracturing is a mainstream technology for unconventional oil and gas reservoirs development all over the world. How to use this technology to achieve high-level oil and gas resource extraction and how to form complex fracture networks as hydrocarbon transportation channels in tight reservoirs, which depends to a large extent on the interaction between hydraulic and pre-existing cracks. For hydraulic fracturing of fractured reservoirs, the impact of natural fractures, perforation direction, stress disturbances, faults and other influencing factors will produce a mixed Ⅰ&Ⅱ mode hydraulic fracture. To forecast whether hydraulic fractures cross pre-existing fractures, according to elastic mechanics and fracture mechanics, a stress state of cracks under the combination of tensile (Ⅰ) and shear (Ⅱ) is presented. A simple mixed-mode Ⅰ&Ⅱ hydraulic fracture's crossing judgment criterion is established, and the propagation of hydraulic fractures after encountering natural fractures is analyzed. The results show that for a given approaching angle there exists a certain range of stress ratio when crossing occurs. Under high approaching angle and large stress ratio, it is likely that hydraulic cracks will go directly through pre-existing cracks. The reinitiated angle is always controlled within the range of approximately 30° among the main direction of penetration.

Relative permeability is a critical factor clarifying the multiphase flow behavior in nano-porous media. However, most studies have focus on the circle flow, neglecting the corner flow effect. Therefore, in this work, a comprehensive relative permeability model considering the corner flow effect is proposed. We integrated the corner flow with the immiscible flow model and the confined liquid-gas phase equilibrium with the near-miscible flow model. Then it was validated against the experimental measured data, indicating the proposed model can well describe the two-phase flow in the confined space. Subsequently, sensitivity analysis of corner number, fractal dimension, minimum radius, and viscosity ratio were conducted. Results show that the corner flow effect is noticeable when corner number is less than 8. Under the optimal pore radius of 2 × 10−5 m, the gas relative permeability increases from 0.4909 to 0.9274 with corner number raising from 4 to 10. Under critical oil phase saturation of 0.175, increase of fraction dimension, minimum radius, and viscosity ratio leads to the significant decrease of oil relative permeability and increase of gas relative permeability. In addition, nano-confinement effect and CO2injection will reduce the interfacial tension and increase the near-miscible relative permeability. When CO2injection increase to 100% under oil saturation of 0.4084, the increment of oil relative permeability is nearly 67.2%. Interfacial intension-based interpolation method indicates that the confined fluid is more likely to be miscible than the bulk fluid. This relative permeability model provides deeper understandings of two-phase flow in the nano-porous media, which is benefit for the better development of unconventional reservoirs.

In myocardial ischemia, hypoxia leads to destruction of the cytoskeleton, and especially the imbalance of microtubule polymerization-depolymerization, which seriously affects the structure and function of cardiomyocytes. We previously showed that a Yiqi HuoxueDecoction (YQHX) improves mitochondrial function and decreases anti-oxidative effects in hypoxia-induced H9c2 cell injury. Therefore, in this study we investigated whether YQHX protects against hypoxia-induced damage by decreasing damage to the cardiac cytoskeleton.

Yiqi HuoxueDecoction (YQHX) has been widely used for clinical treatment of ischemic heart disease. While oxidative stress plays a key role in the pathogenesis of ischemic heart disease, the function and molecular mechanism underlying antioxidative protective effects of YQHX on H9c2 cardiomyocytes against ischemia/hypoxia (I/H) have yet to be well clarified.

To test two theories from traditional Chinese medicine: “exterior–interior relationship between the lung and large intestine” and “treating from the intestine principle for lung disorders”. The influence of intestine-based treatment using Xuan Bai Cheng Qi Tang (XBCQT) on the concentration of three trace elements – copper (Cu), zinc (Zn), and manganese (Mn) – was observed in the tissues of the lung, small intestine, large intestine, and stomach of rats suffering from chronic obstructive pulmonary disease (COPD).

Coalbed methane (CBM) primarily exists in the adsorbed state within coalbeds. Understanding adsorption/desorption of coal to CH4is highly important for estimating CBM reserves, predicting productivity, and enhancing CBM extraction. In this work, the properties of coal, with Ro,m= 0.50–2.54%, adsorbing/desorbing CH4, were quantitatively evaluated. Moreover, the variation characteristics were analyzed utilizing the theories of isosteric heat of adsorption, adsorption potential, and surface free energy. The results show that the D–A and Weibull functions have better fitting accuracy, indicating that there is multilayer adsorption or micropore filling; while considering the physical significance of the formula parameters, the Langmuir and desorption equations are more practical, and as the Ro,mincreases, the VLof samples to CH4presents a “U-shape” change. The isosteric heat of adsorption is proportional to the adsorption amount, but the change rates vary due to the different coverage of CH4, showing that the low- and medium-metamorphic-degree coals change faster. The adsorption potential exhibits a negative correlation with the adsorption volume, and the adsorption potential of high-metamorphic coal is higher, owing to the higher proportion of micropores. As the adsorption progresses, the cumulative decrease in surface free energy of samples rises, but the rate of change gradually decreases. The adsorption heat and potential of the desorption are higher than those of the adsorption process, and the variation of surface free energy is lower; also, the differences become greater with more CH4desorption, revealing the mechanism of the adsorption hysteresis.