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The carbon capture, utilization and storage (CCUS) technique is widely applied in order to solve energy shortages and global warming, in which CO2 storage plays an important part. Herein, the CO2 storage in reservoir pores with a dead-end is investigated using a molecular dynamics simulation. The results indicate that, when a CO2 molecule flows through a reservoir pore towards its dead-end, it is readily captured inside said dead-end. When the pressure difference of the CO2 injection increases, the transport speed of the CO2 becomes faster, and the storage efficiency increases. The rate constants for the absorption of the carbon dioxide at 5 MPa, 10 MPa, and 15 MPa are 0.47 m/s, 2.1 m/s, and 3.1 m/s. With the same main channel, a narrower dead-end with less oil molecules would cause a smaller spatial potential resistance, which would lead to a faster CO2 replacement and storage process. The 3 nm main channel with a 1.5 nm dead-end model had the highest absorption rate of 5.3 m/s out of the three sets of models with different dead-ends. When the dead-end's width was constant, the rate constants for the absorption of carbon dioxide in the 6 nm main channel with a 1.5 nm dead-end model was 1.8 m/s, which was higher than that of the 3 nm–1.5 nm model. This study investigates the mechanism of CO2 storage in reservoir pores with a dead-end at the molecular level and provides a scientific basis for the practical application of CO2 storage. [ABSTRACT FROM AUTHOR]

Because of the growing demand for energy, oil extraction under complicated geological conditions is increasing. Herein, oil displacement by CO2 in wedge-shaped pores was investigated by molecular dynamics simulation. The results showed that, for both single and double wedge-shaped models, pore Ⅱ (pore size from 3 to 8 nm) exhibited a better CO2 flooding ability than pore Ⅰ (pore size from 8 to 3 nm). Compared with slit-shaped pores (3 and 8 nm), the overall oil displacement efficiency followed the sequence of 8 nm > double pore Ⅱ > single pore Ⅱ > 3 nm > double pore Ⅰ > single pore Ⅰ, which confirmed that the exits of the wedge-shaped pores had determinant effects on CO2 enhanced oil recovery over their entrances. "Oil/CO2 inter-pore migration" and "siphoning" phenomena occurred in wedge-shaped double pores by comparing the volumes of oil/CO2 and the center of mass. The results of the interaction and radial distribution function analyses indicate that the wide inlet and outlet had a larger CO2–oil contact surface, better phase miscibility, higher interaction, and faster displacement. These findings clarify the CO2 flooding mechanisms in wedge-shaped pores and provide a scientific basis for the practical applications of CO2 flooding. [ABSTRACT FROM AUTHOR]

• Pregnancy increased expression of PI3K, AKT1, FoxO1, SREBP-1 and PTEN in maternal liver. • Pregnancy increased expression of p-mTOR in maternal liver on days 16 and 25. • Pregnancy increased expression of PPARα in maternal liver, and PI3K in maternal duodenum on day 13. • Pregnancy decreased expression of FXR in maternal liver and duodenum on days 13 and 16, and FoxO1, SREBP-1 and PTEN in maternal duodenum. • Pregnancy increased expression of AKT1 and p-mTOR on day 16, and PPARα in maternal duodenum on day 25. The liver and intestine play a critical role in nutrient absorption, storage, and metabolism. The aim of this study was to evaluate expression pattern of phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of the rapamycin (mTOR) signaling pathway that included PI3K, AKT1, mTOR, FoxO1, SREBP-1, PPARα, PTEN and FXR in the maternal liver and duodenum. Ovine livers and duodenums were sampled at day 16 of the estrous cycle, and at days 13, 16 and 25 of gestation, and RT-qPCR, western blot and immunohistochemistry analysis were used to detect mRNA and protein expression. The results showed that expression of PI3K, AKT1, p-mTOR, FoxO1, SREBP-1 and PTEN upregulated in the maternal liver, and PPARα upregulated in the duodenum. However, expression of FoxO1, SREBP-1 and PTEN in the duodenum downregulated during early pregnancy. In addition, expression levels of SREBP-1, PTEN and PPARα in the maternal liver, and PI3K in the duodenum peaked at day 13 of pregnancy. In addition, expression levels of PI3K, p-mTOR and FoxO1 in the liver, and AKT1 and p-mTOR in the duodenum peaked at day 16 of pregnancy. Nevertheless, expression levels of FXR both in the maternal liver duodenum downregulated at days 13 and 16 of pregnancy. In conclusion, early pregnancy regulated expression pattern of PI3K/AKT/mTOR signaling pathway in the ovine liver and duodenum in a pregnancy stage-specific and tissue-specific manner, which may be necessary for the adaptations in maternal hepatic nutrient metabolism and intestinal nutrient absorption early pregnancy. [ABSTRACT FROM AUTHOR]

The wettability of shale is an important factor affecting oil and gas extraction, and conventional experimental methods are difficult to study at the nanoscale. Moreover, most existing studies are qualitatively based on the wettability of rock surfaces with little consideration for their impact on the CO 2 -EOR. This study employs molecular dynamics simulation methods to conduct an in-depth analysis of the role of rock surface wettability in the CO 2 -enhanced oil recovery (EOR) process. The research findings indicate that as the surface hydroxyl content increases, the adsorption affinity for CO 2 is enhanced, with the selectivity increasing exponentially from 0.74 in the strongly oleophilic wetting (SOW) pore to 3.62 in the strong hydrophilic wetting (SHW) pore. Additionally, variations in wettability result in different types of CO 2 displacement. As oil wettability decreases, the contact interface between CO 2 and oil changes from a convex to a concave shape. Moreover, different types of wettability result in different dynamic contact angle changes over time, which significantly impacts various displacement stages. A comprehensive comparison shows that pores exhibiting oil-wet characteristics reduce the efficiency of the CO 2 -EOR. Finally, the investigation explored the influence of pore structure on oil displacement efficiency. In double pores, when the larger pores exhibit hydrophobic characteristics, they further accelerate the displacement speed of the smaller pores. In connected pores, the presence of notch speeds up the displacement effect within the smaller pores, reducing the impact of wettability on displacement efficiency. This study deeply analyzes the role of shale surface wettability in the CO 2 -EOR process, revealing the impact of wettability on the CO 2 adsorption affinity, fluid displacement, oil displacement efficiency, and flow characteristics of shale oil, providing an important theoretical basis for optimizing the CO 2 -EOR process by adjusting wettability.

The liver plays pivotal roles in nutrient metabolism, and correct hepatic adaptations are required in maternal nutrient metabolism during pregnancy. In this review, hepatic nutrient metabolism, including glucose metabolism, lipid and cholesterol metabolism, and protein and amino acid metabolism, is first addressed. In addition, recent progress on maternal hepatic adaptations in nutrient metabolism during pregnancy is discussed. Finally, the factors that regulate hepatic nutrient metabolism during pregnancy are highlighted, and the factors include follicle-stimulating hormone, estrogen, progesterone, insulin-like growth factor 1, prostaglandins fibroblast growth factor 21, serotonin, growth hormone, adrenocorticotropic hormone, prolactin, thyroid stimulating hormone, melatonin, adrenal hormone, leptin, glucagon-like peptide-1, insulin glucagon and thyroid hormone. Our vision is that more attention should be paid to liver nutrient metabolism during pregnancy, which will be helpful for utilizing nutrient appropriately and efficiently, and avoiding liver diseases during pregnancy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Fang, Li, Wang, Ren, Zhang and Yang.)

Severe CO 2 emissions has posed an increasingly alarming threat, motivating the development of efficient CO 2 capture materials, one of the key parts of carbon capture, utilization, and storage (CCUS). In this study, a series of metal-organic frameworks (MOFs) named Sc-X (X = S, M, L) were constructed inspired by recorded MOFs, Zn-BPZ-SA and MFU-4l-Li. The corresponding isoreticular double-interpenetrating MOFs (Sc-X-IDI) were subsequently constructed via the introduction of isoreticular double interpenetration. Grand canonical Monte Carlo (GCMC) simulations were adopted at 298 K and 0.1-1.0 bar to comprehensively evaluate the CO 2 capture and separation performances in Sc-X and Sc-X-IDI, with gas distribution, isothermal adsorption heat ( Q st ), and van der Waals (vdW)/Coulomb interactions. It is showed that isoreticular double interpenetration significantly improved the interactions between adsorbed gases and frameworks by precisely modulating pore sizes, particularly observed in Sc-M and Sc-M-IDI. Specifically, the Q st and Coulomb interactions exhibited a substantial increase, rising from 28.38 and 22.19 kJ mol -1 in Sc-M to 43.52 and 38.04 kJ mol -1 in Sc-M-IDI, respectively, at 298 K and 1.0 bar. Besides, the selectivity of CO 2 over CH 4 /N 2 was enhanced from 55.36/107.28 in Sc-M to 3308.61/7021.48 in Sc-M-IDI. However, the CO 2 capture capacity is significantly influenced by the pore size. Sc-M, with a favorable pore size, exhibits the highest capture capacity of 15.86 mmol g -1 at 298 K and 1.0 bar. This study elucidated the impact of isoreticular double interpenetration on the CO 2 capture performance in MOFs.

The differences in pore width distributions and connectivity of shale reservoirs have significant influences on supercritical carbon dioxide (scCO 2 )-enhanced oil recovery (CO 2 EOR) in shale. Herein, the molecular dynamics simulation was adopted to investigate the microscopic mechanism of CO 2 EOR in the shale nanopores with different pore size width distributions and pore connectivity. The results show that the pore connectivity has significant effects on the oil displacement, and the recovery efficiency is ordered as: connected pore > double pore > single pore for the 3 nm pore, which are 91.32, 74.43, and 65.93%, respectively. Therefore, the increase in pore connectivity can significantly improve the recovery efficiency of the small pore of the connected pore system. For the shale reservoirs with different pore width distributions, the oil recovery rate of large pores is generally higher than that of small pores. In addition, the displacement of oil in the small pore of the double pore system is accelerated due to the pushing effect of the discharge fluid from the large pore. The results furnish a certain theoretical support for the research of the microscopic mechanism of CO 2 EOR in the shale pore with different pore width distributions and connectivity and the exploit of shale oil.