Here we prepared PEO coatings on Mg alloys in silicate-NaOH-phosphate electrolyte containing different concentrations of NaF addition.The detailed microstructural characterizations combining with potentiodynamic polar...Here we prepared PEO coatings on Mg alloys in silicate-NaOH-phosphate electrolyte containing different concentrations of NaF addition.The detailed microstructural characterizations combining with potentiodynamic polarization and electrochemical impedance spectra(EIS)were employed to investigate the roles of fluoride in the growth and corrosion properties of PEO coating on Mg.The result shows the introduction of NaF led to a fluoride-containing nanolayer(FNL)formed at the Mg/coating interface.The FNL consists of MgO nanoparticles and insoluble MgF_(2)nanoparticles(containing rutile phase and cubic phase).The increase in the NaF concentration of the electrolyte increases the thickness and the MgF_(2)content in the FNL.When anodized in the electrolyte containing 2 g/L NaF,the formed FNL has the highest thickness of 100-200 nm along with the highest value of x of∼0.6 in(MgO)_(1-x)(MgF_(2))x resulted in the highest corrosion performance of PEO coating.In addition,when anodized in the electrolyte containing a low NaF concentration(0.4-0.8 g/L),the formed FNL was thin and discontinuous,which would decrease the pore density and increase the coating's uniformness simultaneously.展开更多
目的探讨团体感觉运动训练对老年精神分裂症患者认知功能、阴性症状干预效果。方法选取63例老年精神科患者,用随机数字表法分为干预组(32例)和对照组(31例),干预组在精神科常规护理基础上进行团体感觉运动训练,每周3次,共24次,两组干预...目的探讨团体感觉运动训练对老年精神分裂症患者认知功能、阴性症状干预效果。方法选取63例老年精神科患者,用随机数字表法分为干预组(32例)和对照组(31例),干预组在精神科常规护理基础上进行团体感觉运动训练,每周3次,共24次,两组干预前后采用简易智能状态检查表(mini-mental state examination,MMSE)、阴性症状量表(scale for the assessment of negative symptoms,SANS)和改良Barthel指数(modified Barthelindex,MBI)评定干预效果,随访6个月比较患者复发率。结果干预8周后,干预组MMSE、MBI总分高于对照组,干预组SANS总分低于对照组,差异均有统计学意义(均P<0.05);干预组MMSE、MBI总分高于干预前,SANS总分低于干预前,差异均有统计学意义(均P<0.05);对照组MMSE、MBI、SANS总分干预前后差异均无统计学意义(均P>0.05);干预组复发率低于对照组(P<0.05)。结论团体感觉运动训练能改善老年精神分裂症患者认知功能和阴性症状,提高日常生活能力,降低复发率。展开更多
基金Zhu.L.and Li.H.contributed equally to this work.This work is supported by the National Natural Science Foundation of China(Grant No.51901121)the Natural Science Foundation of Shaanxi Province(Grant No.2021JM-203,2019JQ-433,2020zdzx04-03-02)the Fundamental Research Funds for the Central Universities(Grant No.GK202103022).
文摘Here we prepared PEO coatings on Mg alloys in silicate-NaOH-phosphate electrolyte containing different concentrations of NaF addition.The detailed microstructural characterizations combining with potentiodynamic polarization and electrochemical impedance spectra(EIS)were employed to investigate the roles of fluoride in the growth and corrosion properties of PEO coating on Mg.The result shows the introduction of NaF led to a fluoride-containing nanolayer(FNL)formed at the Mg/coating interface.The FNL consists of MgO nanoparticles and insoluble MgF_(2)nanoparticles(containing rutile phase and cubic phase).The increase in the NaF concentration of the electrolyte increases the thickness and the MgF_(2)content in the FNL.When anodized in the electrolyte containing 2 g/L NaF,the formed FNL has the highest thickness of 100-200 nm along with the highest value of x of∼0.6 in(MgO)_(1-x)(MgF_(2))x resulted in the highest corrosion performance of PEO coating.In addition,when anodized in the electrolyte containing a low NaF concentration(0.4-0.8 g/L),the formed FNL was thin and discontinuous,which would decrease the pore density and increase the coating's uniformness simultaneously.
文摘目的探讨团体感觉运动训练对老年精神分裂症患者认知功能、阴性症状干预效果。方法选取63例老年精神科患者,用随机数字表法分为干预组(32例)和对照组(31例),干预组在精神科常规护理基础上进行团体感觉运动训练,每周3次,共24次,两组干预前后采用简易智能状态检查表(mini-mental state examination,MMSE)、阴性症状量表(scale for the assessment of negative symptoms,SANS)和改良Barthel指数(modified Barthelindex,MBI)评定干预效果,随访6个月比较患者复发率。结果干预8周后,干预组MMSE、MBI总分高于对照组,干预组SANS总分低于对照组,差异均有统计学意义(均P<0.05);干预组MMSE、MBI总分高于干预前,SANS总分低于干预前,差异均有统计学意义(均P<0.05);对照组MMSE、MBI、SANS总分干预前后差异均无统计学意义(均P>0.05);干预组复发率低于对照组(P<0.05)。结论团体感觉运动训练能改善老年精神分裂症患者认知功能和阴性症状,提高日常生活能力,降低复发率。
文摘一般大跨连续钢箱梁人行桥难以满足我国现行规范对人行桥竖向自振频率的严苛要求(不应小于3 Hz)。为了对此类桥梁的人致振动舒适性进行适合准确的评价及优化,并为我国人行桥有关规范的制定提供依据,以一座(58.6+110+58.6)m大跨连续钢箱梁人行桥为例,参照德国人行桥设计指南(EN03-2008),以人群动荷载作用下结构的加速度幅值为指标对该桥的人致振动舒适性进行评价,并对舒适性不满足要求的特定模态采用布置调质阻尼器(TMD)的方法进行减振处理。分析研究表明:TMD可有效地控制结构相关模态下的人致振动响应,在人行桥第1、第3阶模态峰值位置布置总重6000 kg TMD后,两阶模态的人致振动减振率分别为86.5%、86.3%,最大竖向加速度幅值在0.5 m/s^2以下,满足设计指南最好舒适性指标。
