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To study the corrosion behavior of three commonly used steels in associated gas pipelines in the three-gas coexistence system of H2S-CO2-O2 can provide guidance for the corrosion prevention and control of associated gas pipelines in Tahe oilfield.Based on the typical corrosion working conditions in Tahe oilfield and taking 20 steel，L245NS steel and 3Cr steel as the research objects，the corrosion rates and corrosion products of the three steels under typical working conditions in H2S - CO2- O2 coexistence system were studied through high -temperature and high-pressure reactor experiment.Results showed that the corrosion rate of 20＃ steel was the highest，followed by L245NS steel，and the corrosion rate of 3Cr steel was the lowest.The corrosion products of the three pipes were mainly Fe，FeS，FeCO3 and Fe2O3.The corrosion resistance behaviors of four typical internal anti-corrosion coatings in Tahe oilfield were studied through an adhesion test and the weight gain method that involved the measuring of the weight gain before and after corrosion，and the results indicated that coating 2 possessed the optimal corrosion resistance and adhesion.Considering the cost performance，“L245NS+coating 2”was finally selected as the anti-corrosion measure for the associated gas pipelines in Tahe Oilfield.

To make an effective correlation analysis on the factors influencing the corrosion and perforation of high sulfur associated gas pipeline in Tahe Oilfield, the pipeline flow parameters were calculated using multiphase flow transient model, and a method combining Pearson correlation coefficient with Apriori association rule mining algorithm was proposed to determine the associativity rules that affecting corrosion perforation. Results showed that the multiphase flow transient model revealed the variation laws of pipeline temperature, pressure, flow rate, and liquid holdup along the pipeline. Meanwhile, the degrees of influences of medium parameters and flow parameters on corrosion were as follow: liquid holdup (0.732) > temperature (0.696) > pressure (0.677) =CO2 partial pressure (0.677) = H2S partial pressure (0.677) > gas flow rate (0.618) = gas wall shear force (0.618) > pipe inclination (0.577). The strong correlation rules between the corrosion rate and H2S partial pressure, temperature, liquid holdup, flow rate and pipeline inclination were determined. Besides, the correctness of the association rules was further verified by the high temperature and high pressure dynamic reactor experiment.

With the extension of oilfield production life and the complication of its service environmental conditions, the applicability of the inner coating would be being challenged. In this work, the service condition of epoxy black ceramic coating in Tahe oilfield was simulated by using high-temperature autoclave to study the corrosion resistance of coatings in gas, oil and water phases, and the electrochemical characteristics of the coating in 6 kinds of simulated working conditions such as H2S dominated, H2S / CO2 coexistence and CO2 dominated were analyzed by the electrochemical AC impedance technique (EIS). Results showed that the epoxy black ceramic coating possessed good corrosion resistance characteristics under working conditions, and the AC impedance value was higher than 107 Ω·cm2. From the filed application, the coating had good adhesion to the substrate and good cathodic stripping resistance. Moreover, the failure mechanism of coatings was discussed preliminarily, and their service life under field conditions was preliminarily predicted. Coating defects became a fast channel for the diffusion of water and various ions, electrochemical corrosion occurred at the interface between the coating and the substrate, resulting in the increase of local pressure at the interface and the blistering and cracking of the coating. Furthermore, the life of epoxy black ceramic coating predicted by quadratic polynomial of fitting curve was 517 d.

In order to clarify the stress situation of buried elbow in a certain sulfur oil and gas field, by analyzing the stress factors of a buried elbow in this oil field, the stress parameters affecting the elbow are simulated and calculated.Results showed that the stress at the elbow increased with the increase of the operating temperature, and it presented approximately linear relationship.Under operating conditions with higher operating temperature, the stress at the elbow decreased as the operating pressure increased.Under operating conditions with lower operating temperature, the stress at the elbow increased with increasing operating pressure.Moreover, the stress at the elbow increased first and then decreased as the angle of the elbow increased.According to the change rule of the influence of various factors on the stress of the elbow, the influence factors of the comprehensive parameters of stress evaluation at the elbow were determined, and the stress risk of the elbow in the field engineering was quickly investigated.

Objective To dynamically observe the changes in hypoxia-inducible factor 1α (HIF-1α) and Bcl-2/adenovirus E1B19kDa-interacting protein 3 (BNIP3) in children with traumatic brain injury (TBI) and evaluate their clinical value in predicting the severity and prognosis of pediatric TBI. Methods A prospective study included 47 children with moderate to severe TBI from January 2021 to July 2023, categorized into moderate (scores 9-12) and severe (scores 3-8) subgroups based on the Glasgow Coma Scale. A control group consisted of 30 children diagnosed and treated for inguinal hernia during the same period, with no underlying diseases. The levels of HIF-1α, BNIP3, autophagy- related protein Beclin-1, and S100B were compared among groups. The predictive value of HIF-1α, BNIP3, Beclin-1, and S100B for the severity and prognosis of TBI was assessed using receiver operating characteristic (ROC) curves. Results Serum levels of HIF-1α, BNIP3, Beclin-1, and S100B in the TBI group were higher than those in the control group (P<0.05). Among the TBI patients, the severe subgroup had higher levels of HIF-1α, BNIP3, Beclin-1, and S100B than the moderate subgroup (P<0.05). Correlation analysis showed that the serum levels of HIF-1α, BNIP3, Beclin-1, and S100B wcrc negatively correlated with the Glasgow Coma Scalc scorcs (P<0.05). After 7 days of treatment, scrum levels of HIF-1α, BNIP3, Beclin-1, and S100B in both non-surgical and surgical TBI patients decreased compared to before treatment (P<0.05). ROC curve analysis indicated that the areas under the curve for predicting severe TBI based on scrum levels of HIF-1α, BNIP3, Beclin-1, and S100B wcrc 0.782, 0.835, 0.872, and 0.880, respectively (P<0.05), and for predicting poor prognosis of TBI wcrc 0.749, 0.775, 0.814, and 0.751, respectively (P<0.05). Conclusions Scrum levels of HIF-1α, BNIP3, and Beclin-1 arc significantly elevated in children with TBI, and their measurement can aid in the clinical assessment of the severity and prognosis of pediatric TBI. [ABSTRACT FROM AUTHOR]

Transient receptor potential vanilloid 4 (TRPV4) plays a role in regulating pulmonary fibrosis (PF). While several TRPV4 antagonists including magnolol (MAG), have been discovered, the mechanism of action is not fully understood. This study aimed to investigate the effect of MAG on alleviating fibrosis in chronic obstructive pulmonary disease (COPD) based on TRPV4, and to further analyze its mechanism of action on TRPV4. COPD was induced using cigarette smoke and LPS. The therapeutic effect of MAG on COPD‐induced fibrosis was evaluated. TRPV4 was identified as the main target protein of MAG using target protein capture with MAG probe and drug affinity response target stability assay. The binding sites of MAG at TRPV4 were analyzed using molecular docking and small molecule interaction with TRPV4‐ankyrin repeat domain (ARD). The effects of MAG on TRPV4 membrane distribution and channel activity were analyzed by co‐immunoprecipitation, fluorescence co‐localization, and living cell assay of calcium levels. By targeting TRPV4‐ARD, MAG disrupted the binding between phosphatidylinositol 3 kinase γ and TRPV4, leading to hampered membrane distribution on fibroblasts. Additionally, MAG competitively impaired ATP binding to TRPV4‐ARD, inhibiting TRPV4 channel opening activity. MAG effectively blocked the fibrotic process caused by mechanical or inflammatory signals, thus alleviating PF in COPD. Targeting TRPV4‐ARD presents a novel treatment strategy for PF in COPD. [ABSTRACT FROM AUTHOR]

Heparins are natural and partially degraded polyelectrolytes that consist of sulfated polysaccharide backbones. However, as clinically used anticoagulants, heparins are associated with clinical bleeding risks and thus require rapid neutralization. Protamine sulfate is the only clinically approved antidote for unfractionated heparin (UFH), which not only may cause severe adverse reactions in patients, but also is only partially effective against low molecular weight heparins (LMWHs). We here present the facile synthesis of four porous multicationic dynamic covalent polymers (DCPs) from the condensation of tritopic aldehyde and acylhydrazine precursors. We show that, as new water-soluble polymeric antidotes, the new DCPs can effectively include both UFH and LMWHs and thus reverse their anticoagulating activity, which is confirmed by the activated partial thromboplastin time and thromboelastographic assays as well as mouse tail transection assay (bleeding model). The neutralization activities of two of the DCPs were found to be overall superior to that of protamine and have wider concentration windows and good biocompatibility. This pore-inclusion neutralization strategy paves the way for the development of water-soluble polymers as universal heparin binding agents. [ABSTRACT FROM AUTHOR]