The service water environment of high temperature and high pressure was simulated for the steam generator heat transfer tube of pressurized water reactor.690 TT alloy tube and 405 SS plate were used to form the fricti...The service water environment of high temperature and high pressure was simulated for the steam generator heat transfer tube of pressurized water reactor.690 TT alloy tube and 405 SS plate were used to form the friction pair for impact slip dual-axis fretting corrosion experiments.The microstructure evolution of 690 TT alloy tube during dual-axis impact slip fretting corrosion was investigated.White light interferometer,scanning electron microscope,transmission electron microscope,and Raman spectrum were used to investigate the microstructure and abrasive products of the abraded surface and near-surface.Results indicate that within 105 cycles,the wear mechanism of 690 TT alloy tube is mainly adhesive wear accompanied by material transfer.With the increase in cycles from 5×10^(5) to 2×10^(6),the wear mechanism of 690 TT alloy tube is mainly crack initiation,propagation,and delamination.In terms of microstructure evolution,mixed layer exists under the three body layer in the cross-section microstructure of samples after 105 cycles.The microstructures of samples after 5×10^(5) and 2×10^(6) cycles show slight difference and present a tribological transfer structure layer with thickness of about 500 nm.Additionally,the microstructure evolution enters the stable stage.展开更多
探究基于“-TT”结构经监护仪腹内压监测法降低重症患者喂养不耐受发生率的效果。选取2022年8月—2023年8月四川省自贡市第四人民医院抢救监护室(emergency intensive care unit,EICU)60例重症需行肠内营养(enteral nutrition,EN)支持...探究基于“-TT”结构经监护仪腹内压监测法降低重症患者喂养不耐受发生率的效果。选取2022年8月—2023年8月四川省自贡市第四人民医院抢救监护室(emergency intensive care unit,EICU)60例重症需行肠内营养(enteral nutrition,EN)支持的患者作为研究对象,采用随机数字表法将患者分为参照组和试验组,每组各30例。参照组实施常规EN管理,试验组在参照组基础上实施基于“-TT”结构经监护仪腹内压监测法,对比两组患者的喂养不耐受发生率。结果显示,与参照组相比,试验组喂养不耐受发生率较低(P<0.05);试验组达到目标喂养量时间较短(P<0.05);试验组EICU停留时间较短(P<0.05)。研究发现,于EICU重症需行EN支持患者的管理中,基于“-TT”结构经监护仪腹内压监测法具有一定的临床应用价值,通过对患者腹压变化的实时监测,可以及时调整喂养方案,降低其喂养不耐受发生率,缩短患者达到目标喂养量的时间,改善患者预后,值得借鉴。展开更多
基金National Key Research and Development Program of China(2019YFB1900904)。
文摘The service water environment of high temperature and high pressure was simulated for the steam generator heat transfer tube of pressurized water reactor.690 TT alloy tube and 405 SS plate were used to form the friction pair for impact slip dual-axis fretting corrosion experiments.The microstructure evolution of 690 TT alloy tube during dual-axis impact slip fretting corrosion was investigated.White light interferometer,scanning electron microscope,transmission electron microscope,and Raman spectrum were used to investigate the microstructure and abrasive products of the abraded surface and near-surface.Results indicate that within 105 cycles,the wear mechanism of 690 TT alloy tube is mainly adhesive wear accompanied by material transfer.With the increase in cycles from 5×10^(5) to 2×10^(6),the wear mechanism of 690 TT alloy tube is mainly crack initiation,propagation,and delamination.In terms of microstructure evolution,mixed layer exists under the three body layer in the cross-section microstructure of samples after 105 cycles.The microstructures of samples after 5×10^(5) and 2×10^(6) cycles show slight difference and present a tribological transfer structure layer with thickness of about 500 nm.Additionally,the microstructure evolution enters the stable stage.
文摘探究基于“-TT”结构经监护仪腹内压监测法降低重症患者喂养不耐受发生率的效果。选取2022年8月—2023年8月四川省自贡市第四人民医院抢救监护室(emergency intensive care unit,EICU)60例重症需行肠内营养(enteral nutrition,EN)支持的患者作为研究对象,采用随机数字表法将患者分为参照组和试验组,每组各30例。参照组实施常规EN管理,试验组在参照组基础上实施基于“-TT”结构经监护仪腹内压监测法,对比两组患者的喂养不耐受发生率。结果显示,与参照组相比,试验组喂养不耐受发生率较低(P<0.05);试验组达到目标喂养量时间较短(P<0.05);试验组EICU停留时间较短(P<0.05)。研究发现,于EICU重症需行EN支持患者的管理中,基于“-TT”结构经监护仪腹内压监测法具有一定的临床应用价值,通过对患者腹压变化的实时监测,可以及时调整喂养方案,降低其喂养不耐受发生率,缩短患者达到目标喂养量的时间,改善患者预后,值得借鉴。
