Erosion-corrosion and its mitigation on the internal surface of the expansion segment of N80 steel tube

We investigated erosion-corrosion(E-C) and its mitigation on the internal surface of the expansion segment of N80 steel tube in a loop system using array electrode technique, weight-loss measurement, computational-fluid-dynamics simulation, and surface characterization techniques.The results show that high E-C rates can occur at locations where there is a high flow velocity and/or a strong impact from sand particles, which results in different E-C rates at various locations.Consequently, it can be expected that localized corrosion often occurs in such segments.The E-C rate at each location in the expansion segment can be significantly mitigated with an imidazoline derivative inhibitor, as the resulting inhibitor layer significantly impedes the electrochemical reaction rate.However, we found that this inhibitor layer could not effectively reduce the difference in the erosion rates at different locations on the internal surface of the expansion segment.This means that localized corrosion can still occur at the expansion segment despite the presence of the inhibitor.

Severe pneumonia and acute myocardial infarction complicated with pericarditis after percutaneous coronary intervention:A case report

BACKGROUND Cases of severe pneumonia complicated with acute myocardial infarction(AMI)with good prognosis after percutaneous coronary intervention(PCI)are rare,especially those with postoperative pericarditis and intestinal obstruction.CASE SUMMARY A 53-year-old male patient was admitted to the emergency department of our hospital because of paroxysmal chest tightness for 4 d,aggravated with chest pain for 12 h.The symptoms,electrocardiography,biochemical parameters,echocardiography and chest computed tomography confirmed the diagnosis of severe pneumonia complicated with AMI.The patient was treated with antiplatelet aggregation,anticoagulation,lipid regulation,vasodilation,anti-infective agents and direct PCI.The patient was discharged after 3 wk of treatment.Follow-up showed that the patient was asymptomatic without recurrence.CONCLUSION For patients with severe pneumonia complicated with AMI,PCI and antibiotic therapy is a life-saving strategy.

水-土特征曲线的分段对估测非饱和渗透系数的影响（英文）

目的:在采用统计法估测非饱和渗透系数的过程中,探讨水-土特征曲线分段的不同方法和不同数量对估测结果的影响。创新点:比较在体积含水量区间和土吸力区间分割水-土特征曲线对估测非饱和渗透系数的影响;最终建议在土吸力区间分割水-土特征曲线。方法:采用现有模型和数学公式,对比不同类型土质(单峰和双峰水-土特征曲线)估测和实验测量的非饱和渗透系数。结论:1.传统的在体积含水量区间分割水-土特征曲线会造成对低吸力区域的非饱和渗透系数的估测不够精确。2.综合比较单峰和双峰的水-土特征曲线及2种不同分割水-土特征曲线的方法,发现在分段大于40片时,估测结果非常接近实验结果。因此,在采用统计法估测土体的非饱和渗透系数时,建议在土吸力区间对水-土特征曲线进行分割,且分割数量应该大于40。