Li_(2)O-Al_(2)O_(3)-SiO_(2) based glasses were investigated as potential protection glass for electronic devices due to their excellent mechanical properties,such as high hardness,toughness,and scratch resistance.In t...Li_(2)O-Al_(2)O_(3)-SiO_(2) based glasses were investigated as potential protection glass for electronic devices due to their excellent mechanical properties,such as high hardness,toughness,and scratch resistance.In this paper,Li_(2)O-Na_(2)O-Al_(2)O_(3)-SiO_(2) glass with different Li_(2)O/Na_(2)O ratio components were prepared by meltquenching method,and the effects of Na_(2)O/Li_(2)O ratio on the glass densities,structure,thermal,mechanical properties,and chemical stabilities were studied.The experimental results indicate that the glass transition temperature increases with the increases in Na_(2)O/Li_(2)O ratios,due to larger ion radius.While the thermal expansion coefficient slightly decreases from 11.4×10^(-6) to 11.09×10^(-6)/℃.The elastic modulus increases from 57 to 72 GPa.The bending strength reaches maximum 80.90 MPa when the Na_(2)O/Li_(2)O ratio is 1.7,then decreases as the ratio further increases.In addition,the Vicker’s hardness gets to 7.37 GPa with largest Na_(2)O/Li_(2)O ratio.Moreover,the dielectric loss and dielectric constant increases as the ratio increases.The Raman structure analysis shows the Q4[Si-O-Si]decreases as Na_(2)O/Li_(2)O ratio increases,which is responsible for the characteristic properties change.Moreover,the glass shows lowest mass loss in 10vol%HF solutions when the ratio is 1.4,while 1.7 in 5wt%NaOH solution.展开更多
目的通过对Web of Science数据库核心合集中护理领域关于心理痛苦研究的文献进行可视化分析,为提高临床患者生命质量,制定有针对性的护理措施提供参考。方法应用CiteSpace V信息可视化软件,对2008年1月1日至2017年12月31日Web of Scienc...目的通过对Web of Science数据库核心合集中护理领域关于心理痛苦研究的文献进行可视化分析,为提高临床患者生命质量,制定有针对性的护理措施提供参考。方法应用CiteSpace V信息可视化软件,对2008年1月1日至2017年12月31日Web of Science数据库核心合集中护理领域关于心理痛苦研究的共854篇文献进行可视化分析,绘制出研究热点、研究前沿的知识图谱。结果近10年SCI在护理领域关于心理痛苦研究的发文量总体呈上升趋势;研究热点主要围绕抑郁、压力、乳腺癌、焦虑等关键词展开;在Web of Science数据库核心合集中,美国发文量最高,中国大陆居第5位,中国台湾居第7位。结论中国在护理领域心理痛苦的研究还落后于西方发达国家,中国的护理人员还应努力。展开更多
基金by the Key Research Project of Hainan Province(No.ZDYF2021GXJS027)the Shenzhen Free Investigation Fundamental Research Project(2021Szvup107)。
文摘Li_(2)O-Al_(2)O_(3)-SiO_(2) based glasses were investigated as potential protection glass for electronic devices due to their excellent mechanical properties,such as high hardness,toughness,and scratch resistance.In this paper,Li_(2)O-Na_(2)O-Al_(2)O_(3)-SiO_(2) glass with different Li_(2)O/Na_(2)O ratio components were prepared by meltquenching method,and the effects of Na_(2)O/Li_(2)O ratio on the glass densities,structure,thermal,mechanical properties,and chemical stabilities were studied.The experimental results indicate that the glass transition temperature increases with the increases in Na_(2)O/Li_(2)O ratios,due to larger ion radius.While the thermal expansion coefficient slightly decreases from 11.4×10^(-6) to 11.09×10^(-6)/℃.The elastic modulus increases from 57 to 72 GPa.The bending strength reaches maximum 80.90 MPa when the Na_(2)O/Li_(2)O ratio is 1.7,then decreases as the ratio further increases.In addition,the Vicker’s hardness gets to 7.37 GPa with largest Na_(2)O/Li_(2)O ratio.Moreover,the dielectric loss and dielectric constant increases as the ratio increases.The Raman structure analysis shows the Q4[Si-O-Si]decreases as Na_(2)O/Li_(2)O ratio increases,which is responsible for the characteristic properties change.Moreover,the glass shows lowest mass loss in 10vol%HF solutions when the ratio is 1.4,while 1.7 in 5wt%NaOH solution.
文摘目的通过对Web of Science数据库核心合集中护理领域关于心理痛苦研究的文献进行可视化分析,为提高临床患者生命质量,制定有针对性的护理措施提供参考。方法应用CiteSpace V信息可视化软件,对2008年1月1日至2017年12月31日Web of Science数据库核心合集中护理领域关于心理痛苦研究的共854篇文献进行可视化分析,绘制出研究热点、研究前沿的知识图谱。结果近10年SCI在护理领域关于心理痛苦研究的发文量总体呈上升趋势;研究热点主要围绕抑郁、压力、乳腺癌、焦虑等关键词展开;在Web of Science数据库核心合集中,美国发文量最高,中国大陆居第5位,中国台湾居第7位。结论中国在护理领域心理痛苦的研究还落后于西方发达国家,中国的护理人员还应努力。
