Thermal barrier coatings(TBCs) have been widely applied to protect metallic components in gas turbines or aero engine against the high temperatures.In the recent decade,considerable numerical models have been built up...Thermal barrier coatings(TBCs) have been widely applied to protect metallic components in gas turbines or aero engine against the high temperatures.In the recent decade,considerable numerical models have been built up to present the thermal spray process.However,much less work has focused on the prediction of the insulation temperature to the TBCs,which is an important parameter to affect the performance of the TBCs during their applications.In the present study,a 3D finite element simulation has been carried out to predict the heat insulation behavior of the 6%～8%yittria partially stabilized zirconia coatings based on a two-layer model.Furthermore,such factors as the heat transfer mode,the thickness of the coating,properties of the coating as well as the microstructure of the coating have been numerically investigated. The significance of the finding is also discussed.展开更多
文摘Thermal barrier coatings(TBCs) have been widely applied to protect metallic components in gas turbines or aero engine against the high temperatures.In the recent decade,considerable numerical models have been built up to present the thermal spray process.However,much less work has focused on the prediction of the insulation temperature to the TBCs,which is an important parameter to affect the performance of the TBCs during their applications.In the present study,a 3D finite element simulation has been carried out to predict the heat insulation behavior of the 6%～8%yittria partially stabilized zirconia coatings based on a two-layer model.Furthermore,such factors as the heat transfer mode,the thickness of the coating,properties of the coating as well as the microstructure of the coating have been numerically investigated. The significance of the finding is also discussed.
文摘目的:探讨早期康复锻炼对心脏外科术后患者预后的影响。方法:选取2016年1月至2018年1月期间在我院成人心脏外科术后重症监护室(ICU)停留大于48 h患者893例,根据是否开展早期康复锻炼分为早期康复组239例和传统治疗组654例,经过倾向性评分进行1:1匹配每组192例,分析两组患者预后指标差异。结果:早期康复组与传统治疗组比较,机械通气时间缩短[(36.0±14.9)hvs (43.0±12.5)h,P=0.016],镇静药物使用减少[(39.0±16.8)h vs (47.0±21.3)h,P=0.001],谵妄发生率降低(7.81%vs 17.19%,P=0.006),肠道功能紊乱发生率降低(26.56%vs 42.71%,P=0.001),营养不良风险降低[肱三头肌皮褶厚度(12.0±3.3) mm vs(15.0±2.8) mm,P=0.021],但两组患者ICU停留时间、院内感染发生率、器械辅助使用率、气管切开、非计划拔管、空肠营养管置管及运动耐量随访等指标差异均无统计学意义(P均>0.05)。结论:心脏外科术后早期康复锻炼对患者预后指标有一定改善。
