Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.D...Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.Different from the traditional Mg-Zn alloys preparation methods,alloys prepared by gas-phase alloying have a large number of intermetallic compounds,such as MgZn,Mg7Zn3 and MgZn2.After solution treatment,the boundary of the eutectic disappeared and the size ofα-Mg increased from 100μm to 150μm.At the same time,the value of the resistance of charge transfer increased,which indicates that the resistance of the charge transfer and the corrosion resistance of the alloys increased.After artificial aging treatment,the distribution ofα-Mg was more uniform and its size was reduced to about 50μm,and there was new eutectic structure formed.The newly formed eutectic structure forms galvanic cells with the alloy matrix,which makes the corrosion resistance of the alloy weaken.展开更多
目的:探讨成人和儿童术前乳酸林格氏液液体动力学的差别。方法:本研究是随机,双盲前瞻性研究。择期盆腔、肛肠或者下肢小手术患者28例,美国麻醉医师协会(ASA)I级,其中儿童14例,成人14例。所有患者给予镇静药后在20 min内恒速输入10 m L...目的:探讨成人和儿童术前乳酸林格氏液液体动力学的差别。方法:本研究是随机,双盲前瞻性研究。择期盆腔、肛肠或者下肢小手术患者28例,美国麻醉医师协会(ASA)I级,其中儿童14例,成人14例。所有患者给予镇静药后在20 min内恒速输入10 m L/kg的乳酸林格氏液体,通过血红蛋白(Hb)稀释-时间曲线和尿量采用Matlab 4.2软件包计算液体动力学参数。结果:一级动力学模型拟合结果显示,与成人相比,在输入林格氏液体后90 min内儿童的血浆稀释程度明显降低(0.16 vs 0.07,P=0.000),儿童将输入液体的43%通过肾脏排出,显著高于成人(18%)(P=0.011)。按公斤体重计算儿童和成人对乳酸林格氏液的血浆清除率分别是2.2 m L·min-1·kg-1和0.5 m L·min-1·kg-1(P=0.016),而肾脏对乳酸林格氏液体的清除率两组分别是0.76 m L·min-1·kg-1和0.10 m L·min-1·kg-1,(P=0.000)。结论:儿童对乳酸林格氏液体血浆和肾脏清除率分别是成人的4倍和7倍,术前给儿童输液,按照体重计算量可以参照成人的剂量。展开更多
基金Project(2015DFR50990-01)supported by the International Cooperation Project of Ministry of Science and Technology of ChinaProject(2016KF-01)supported by the Shaanxi Key Laboratory of Nano-materials and Technology,ChinaProject(2015CXY-01)supported by the Cooperation Project on the Integration of Industry,Education and Research of Yulin Science and Technology Bureau,China。
文摘Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.Different from the traditional Mg-Zn alloys preparation methods,alloys prepared by gas-phase alloying have a large number of intermetallic compounds,such as MgZn,Mg7Zn3 and MgZn2.After solution treatment,the boundary of the eutectic disappeared and the size ofα-Mg increased from 100μm to 150μm.At the same time,the value of the resistance of charge transfer increased,which indicates that the resistance of the charge transfer and the corrosion resistance of the alloys increased.After artificial aging treatment,the distribution ofα-Mg was more uniform and its size was reduced to about 50μm,and there was new eutectic structure formed.The newly formed eutectic structure forms galvanic cells with the alloy matrix,which makes the corrosion resistance of the alloy weaken.
文摘目的:探讨成人和儿童术前乳酸林格氏液液体动力学的差别。方法:本研究是随机,双盲前瞻性研究。择期盆腔、肛肠或者下肢小手术患者28例,美国麻醉医师协会(ASA)I级,其中儿童14例,成人14例。所有患者给予镇静药后在20 min内恒速输入10 m L/kg的乳酸林格氏液体,通过血红蛋白(Hb)稀释-时间曲线和尿量采用Matlab 4.2软件包计算液体动力学参数。结果:一级动力学模型拟合结果显示,与成人相比,在输入林格氏液体后90 min内儿童的血浆稀释程度明显降低(0.16 vs 0.07,P=0.000),儿童将输入液体的43%通过肾脏排出,显著高于成人(18%)(P=0.011)。按公斤体重计算儿童和成人对乳酸林格氏液的血浆清除率分别是2.2 m L·min-1·kg-1和0.5 m L·min-1·kg-1(P=0.016),而肾脏对乳酸林格氏液体的清除率两组分别是0.76 m L·min-1·kg-1和0.10 m L·min-1·kg-1,(P=0.000)。结论:儿童对乳酸林格氏液体血浆和肾脏清除率分别是成人的4倍和7倍,术前给儿童输液,按照体重计算量可以参照成人的剂量。