We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic ...We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were investigated.Scanning electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic performance.Due to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly improved.Mullite sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by UHPC.The stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of UHPC.This study will provide a reference for developing UHPC with superior elastic modulus for structural engineering.展开更多
目的 以山东省57家三级综合医院为研究样本,评价其医疗质量与运营效率状况,为加强医院内涵建设、提升精细化管理水平提供参考依据。方法 通过构建评价指标体系,运用熵权逼近理想解排序法(technique for order preference by similarity ...目的 以山东省57家三级综合医院为研究样本,评价其医疗质量与运营效率状况,为加强医院内涵建设、提升精细化管理水平提供参考依据。方法 通过构建评价指标体系,运用熵权逼近理想解排序法(technique for order preference by similarity to ideal solution, TOPSIS)与数据包络分析法(data envelopmentanalysis, DEA)分别对样本医院的医疗质量及运营效率水平进行评价分析。结果 医疗质量方面,样本医院间四级手术占比和CMI差异较大,且权重最大;质量水平排名靠前的医院为A1、A2、A3、A4、A29,均为三级甲等医院,且多为省属医院。运营效率方面,57家样本医院整体运营效率较高,但医院间发展不均衡,其中22家医院DEA有效,12家医院DEA弱有效,23家医院DEA无效。医疗质量与纯技术效率之间存在正相关关系。结论 部分样本医院医疗质量与运营效率有较大改进空间,应聚焦功能定位,在医疗技术水平、资源配置和内部管理能力等方面持续改进和提升,从规模扩张转向提质增效,助力医院高质量发展。展开更多
基金Funed by the National Natural Science Foundation of China(No.U21A20149)the Ecological Environment Scientific Research Project of Anhui Province(No.2023hb0014)+2 种基金the Research Reserve of Anhui Jianzhu University(No.2022XMK01)the Excellent Scientific Research and Innovation Team in Colleges and Universities of Anhui Province(No.2022AH010017)Research on the preparation technology of self compacting concrete with strength grade C100.
文摘We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were investigated.Scanning electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic performance.Due to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly improved.Mullite sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by UHPC.The stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of UHPC.This study will provide a reference for developing UHPC with superior elastic modulus for structural engineering.
文摘目的 以山东省57家三级综合医院为研究样本,评价其医疗质量与运营效率状况,为加强医院内涵建设、提升精细化管理水平提供参考依据。方法 通过构建评价指标体系,运用熵权逼近理想解排序法(technique for order preference by similarity to ideal solution, TOPSIS)与数据包络分析法(data envelopmentanalysis, DEA)分别对样本医院的医疗质量及运营效率水平进行评价分析。结果 医疗质量方面,样本医院间四级手术占比和CMI差异较大,且权重最大;质量水平排名靠前的医院为A1、A2、A3、A4、A29,均为三级甲等医院,且多为省属医院。运营效率方面,57家样本医院整体运营效率较高,但医院间发展不均衡,其中22家医院DEA有效,12家医院DEA弱有效,23家医院DEA无效。医疗质量与纯技术效率之间存在正相关关系。结论 部分样本医院医疗质量与运营效率有较大改进空间,应聚焦功能定位,在医疗技术水平、资源配置和内部管理能力等方面持续改进和提升,从规模扩张转向提质增效,助力医院高质量发展。
