A cross-linkable comonomer containing a diacetylene group,named dimethyl 4,4＇-（buta-l,3-diyne-l,4-diyl）dibenzoate（DA） was synthesized and copolymerized with dimethyl succinate and 1,4-butanediol to prepare a seri...A cross-linkable comonomer containing a diacetylene group,named dimethyl 4,4＇-（buta-l,3-diyne-l,4-diyl）dibenzoate（DA） was synthesized and copolymerized with dimethyl succinate and 1,4-butanediol to prepare a series of slightly cross-linked PBS copolyesters（PBDASx）.The chemical structure,crystallization and Theological behaviours of PBDASx were well investigated.Compared to neat PBS,PBDASx showed the greatly increased crystallization rate because of the promoting nucleation of the cross-linking domains,and the XRD results indicated that it had no influence on crystallization structure of PBS.The rheological behaviours indicate that PBDASx possessed higher viscosity than neat PBS even at high shear rate and temperature.PBDAS0.3 exhibited better comprehensive properties than neat PBS,which will widen applications of PBS.展开更多
This paper deals. with the problem of dynamic response of platform-cylinder group foumdation. Dynamic interaction of cylinder group foudation-water-soil is taken into account and the analysis of dynamic response to ex...This paper deals. with the problem of dynamic response of platform-cylinder group foumdation. Dynamic interaction of cylinder group foudation-water-soil is taken into account and the analysis of dynamic response to excitation of water wave force is given by analytic method ..The numerical examples are presented and the influence of systent’s parameters on the dynamic behaviour is discussed.展开更多
目的:提高全社会对中老年人健康的关注度,从源头上减少健康危险行为的发生,为中老年人的健康管理工作提供参考依据。方法:基于健康生态学模型,利用最新的中国健康和营养调查(China Health and Nutrtion;Survey,CHNS)数据库,对我国≥45...目的:提高全社会对中老年人健康的关注度,从源头上减少健康危险行为的发生,为中老年人的健康管理工作提供参考依据。方法:基于健康生态学模型,利用最新的中国健康和营养调查(China Health and Nutrtion;Survey,CHNS)数据库,对我国≥45岁中老年人的人口学特征与健康危险行为关系进行分析。结果:中老年人健康危险行为共存指数均值为3.5,从个人特质、行为特点、人际关系网络、工作环境,社会政策5个层面建立5个模型。研究结果显示,个人特质、个人行为特点、人际关系网络、工作环境、社会政策均是中老年人群健康危险行为的影响因素,差异有统计学意义(P<0.05)。结论:中老年人自身认知水平有待加强,政府需要优化底层政策逻辑,从源头上提高中老年人自我健康管理意识和健康素养水平。展开更多
基金supported financially by the National Natural Science Foundation of China (Nos. 21634006 and 51121001)the Program for Changjiang Scholars and Innovative Research Teams in University of China (No. IRT1026)
文摘A cross-linkable comonomer containing a diacetylene group,named dimethyl 4,4＇-（buta-l,3-diyne-l,4-diyl）dibenzoate（DA） was synthesized and copolymerized with dimethyl succinate and 1,4-butanediol to prepare a series of slightly cross-linked PBS copolyesters（PBDASx）.The chemical structure,crystallization and Theological behaviours of PBDASx were well investigated.Compared to neat PBS,PBDASx showed the greatly increased crystallization rate because of the promoting nucleation of the cross-linking domains,and the XRD results indicated that it had no influence on crystallization structure of PBS.The rheological behaviours indicate that PBDASx possessed higher viscosity than neat PBS even at high shear rate and temperature.PBDAS0.3 exhibited better comprehensive properties than neat PBS,which will widen applications of PBS.
文摘This paper deals. with the problem of dynamic response of platform-cylinder group foumdation. Dynamic interaction of cylinder group foudation-water-soil is taken into account and the analysis of dynamic response to excitation of water wave force is given by analytic method ..The numerical examples are presented and the influence of systent’s parameters on the dynamic behaviour is discussed.
文摘目的:提高全社会对中老年人健康的关注度,从源头上减少健康危险行为的发生,为中老年人的健康管理工作提供参考依据。方法:基于健康生态学模型,利用最新的中国健康和营养调查(China Health and Nutrtion;Survey,CHNS)数据库,对我国≥45岁中老年人的人口学特征与健康危险行为关系进行分析。结果:中老年人健康危险行为共存指数均值为3.5,从个人特质、行为特点、人际关系网络、工作环境,社会政策5个层面建立5个模型。研究结果显示,个人特质、个人行为特点、人际关系网络、工作环境、社会政策均是中老年人群健康危险行为的影响因素,差异有统计学意义(P<0.05)。结论:中老年人自身认知水平有待加强,政府需要优化底层政策逻辑,从源头上提高中老年人自我健康管理意识和健康素养水平。
