Iatrogenic pneumopericardium after therapeutic pericardiocentesis for pericardial effusion: a case report

Pneumopericardium refers to the presence of air inside the pericardial cavity,which is a rare entity that has been reported clinically.Toledo,et al.[1]classified the causes of pneumopericardium into four categories:iatrogenic,pericarditis,fistula formation between the pericardium and adjacent hollow organs,and trauma.

Research progress on carbon materials as negative electrodes in sodium-and potassium-ion batteries

Carbon materials,including graphite,hard carbon,soft carbon,graphene,and carbon nanotubes,are widely used as high-performance negative electrodes for sodium-ion and potassium-ion batteries(SIBs and PIBs).Compared with other materials,carbon materials are abundant,low-cost,and environmentally friendly,and have excellent electrochemical properties,which make them especially suitable for negative electrode materials of SIBs and PIBs.Compared with traditional carbon materials,modifications of the morphology and size of nanomaterials represent effective strategies to improve the quality of electrode materials.Different nanostructures make different contributions toward improving the electrochemical performance of electrode materials,so the synthesis of nanomaterials is promising for controlling the morphology and size of electrode materials.This paper reviews the progress made and challenges in the use of carbon materials as negative electrode materials for SIBs and PIBs in recent years.The differences in Na+and K+storage mechanisms among different types of carbon materials are emphasized.

Effect of large load on the wear and corrosion behavior of high-strength EH47 hull steel in 3.5wt%NaCl solution with sand

To simulate the wear and corrosion behavior of high-strength EH47 hull steel in a complicated marine environment in which seawater,sea ice,and sea sand coexist,accelerated wear and corrosion tests were performed in a laboratory setting using a tribometer.The effect of large loads on the behavior of abrasion and corrosion in a 3.5wt%NaCl solution with ice and sand to simulate a marine environment were investigated.The experimental results showed that the coefficient of friction(COF)decreases with increasing working load;meanwhile,the loading force and sand on the disk strongly influence the COF.The mechanisms of friction and the coupling effect of abrasion and corrosion in the 3.5wt%NaCl solution with sand were the wear and corrosion mechanisms;furthermore,the wear mechanism exerted the predominant effect.

Hot deformation behavior and microstructure evolution of an Fe–30Cr–2Mo ultra-pure super ferritic stainless steel

The hot deformation behavior and microstructure evolution of an Fe–30Cr–2Mo ultra-pure super ferritic stainless steel were investigated at the temperature range of 950–1150℃ and strain rate varying from 0.01 to 10 s^(−1).A strain compensated constitutive equation based on the Arrhenius-type model was established to predict the flow stress.The hot processing map based on the dynamic materials model was achieved to identify the optimum processing parameters.In addition,the features of microstructure evolution combined with the processing map were systematically investigated.The experimental results revealed that the flow stress increased with decreasing deformation temperature or increasing strain rate.Dynamic recovery was confirmed to be the predominant softening mechanism.The values of flow stress predicted by the strain compensated constitutive equation agreed well with the experimental values.The extent of dynamic recrystallization and recrystallized grain size increased with increasing deformation temperature or decreasing strain rate,and the continuous dynamic recrystallization was attributed to be the predominant mechanism of recrystallization during hot deformation.The optimum hot working parameters were determined to be the deformation temperature of 1070–1150℃ and strain rate of 0.1–1 s^(−1) with a peak power dissipation efficiency of 42%.