Triply periodic minimal surfaces(TPMS)are structures with smooth surfaces and excellent energy absorption properties.Combining new functional materials,such as shape memory alloys,with TPMS structures provides a novel...Triply periodic minimal surfaces(TPMS)are structures with smooth surfaces and excellent energy absorption properties.Combining new functional materials,such as shape memory alloys,with TPMS structures provides a novel and promising research field.In this study,three TPMS structures(Gyroid,Diamond,and Primitive)of Cu-11.85Al-3.2Mn-0.1Ti alloy were printed by laser powder bed fusion,which is favorable for the fabrication of complex structures.The manufacturing fidelity,mechanical response,and superelastic properties of the three structures were investigated.Stress distributions in the three structures during compression were analyzed by finite element(FE)simulation.The three structures were equipped with high-quality,glossy surfaces and uniform pores.However,due to powder adhesion and forming steps,there were volumetric errors and dimensional deviations between the samples and the CAD models.The errors were within 1.6%for the Gyroid and Diamond structures.The dimensional deviations at the nodes in the three structures were less than 0.09 mm.The microstructures of all structures wereβ1´martensite,consistent with the cubic sample.Experimental results of compression showed that the structures underwent a layer-by-layer compression failure mode,and the Primitive structures exhibited a more pronounced oscillatory process.The Diamond structures showed the highest first fracture stress and strain of 164.67 MPa and 13.89%,respectively.It also possessed the lowest yield strength(61.97 MPa)and the best energy absorption properties(7.6 MJ/m3).Through the deformation analysis,the Gyroid and Diamond structures were found to fracture at a 45°direction,while the Primitive structures fractured horizontally.These findings were consistent with the results obtained from the FE simulation,which showed equivalent stress distributions.After applying various pre-strains,the Diamond structures displayed the highest superelastic strain of up to 3.53%.The superelastic recovery of all samples ranged from 63.5%to 71.5%.展开更多
目的分析2000—2022年逍遥散研究现状,并预测其发展趋势,为该复方的进一步研究提供借鉴。方法利用中国学术期刊全文数据库(CNKI)和Web of Science(WoS)核心集数据库,检索逍遥散相关文献,使用CiteSpace软件对发文量趋势、作者、机构、关...目的分析2000—2022年逍遥散研究现状,并预测其发展趋势,为该复方的进一步研究提供借鉴。方法利用中国学术期刊全文数据库(CNKI)和Web of Science(WoS)核心集数据库,检索逍遥散相关文献,使用CiteSpace软件对发文量趋势、作者、机构、关键词等进行可视化分析。结果经数据清洗,得到中文文献956篇,英文文献225篇;自2000年以来,逍遥散发文量呈逐年上升趋势;陈家旭(北京中医药大学)、秦雪梅(山西大学)、曾南(成都中医药大学)是该领域发文量前3的作者,其所在单位同样为主要研究机构;中文文献主要集中在抑郁症、乳腺癌及月经不调等方面,英文文献主要聚焦在抑郁症方面;近年来逍遥散研究热点逐渐由乳腺癌、月经不调、黄褐斑等向抗抑郁领域发展,其抗抑郁症机制主要集中在单胺类神经递质、神经内分泌、神经营养因子、能量代谢、肠道菌群、免疫等方面。但是,目前在逍遥散抗抑郁研究方面存在一些复方应用层面的问题,包括药味组成比例不统一、用药剂量范围过大、单味药是否炮制以及提取方法各有不同等,这将造成所制备的提取物存在较大差异,因此所引起的药效及其作用机制可能也有所不同,这些问题制约了其长远发展。结论逍遥散的研究正处于快速发展阶段,临床应用及实验研究方面已有大量积累,但因抑郁症发病机制复杂,逍遥散抗抑郁机制方面的研究仍需继续深入,如利用同位素示踪代谢组学、肠道微生物组学、单细胞转录组学等对其能量代谢、菌群调节和免疫调控的作用机制进行深入研究,为逍遥散的抗抑郁研究带来突破性创新。展开更多
The main objective of this study is to optimize the fresh and strength properties of reactive powder concrete incorporated with industrial by-products like ultra-fine ground granulated blast furnace slag as cement sub...The main objective of this study is to optimize the fresh and strength properties of reactive powder concrete incorporated with industrial by-products like ultra-fine ground granulated blast furnace slag as cement substitute and added with coal bottom ash and recycled concrete fines as partial replacement of quartz sand by response surface methodology through design of experiment approach.Totally four responses namely slump,compressive strength(C-28),flexural strength(F-28),and split-tensile strength(S-28)after 28 days of curing period were considered.The statistical study on the reactive powder concrete includes the modeling of regression,normal probability plots,surface plot analysis,and optimization of process variables.The regression models of the considered responses(slump,C-28,F-28,and S-28)were tested.The results obtained from the analysis of variance(ANOVA)and Pareto chart were used to determine the statistical significance of the process variables.The influence of the variables on the responses was studied by means of the surface plot analysis.The optimal proportion of the variables against the responses was obtained through optimization response.The resulted regression equations were in the form of second-order polynomial equation and the prediction of strength properties was found to be in line with the experimental results.The difference of proportion of variance indicated that only 0.43%,6.42%,5.15%,and 9.7%of deviations cannot be expressed by the analysis.The ANOVA and Pareto charts represented the high significance and appropriateness of the linear term of slump response and the two-way interaction term of strength responses.The results of the optimization response revealed the optimal proportions of recycled concrete fines and coal bottom ash as 19.15%and 7.02%,respectively.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.52275333,52375335,and U22A202494)the Stabilization Support Project of AVIC Manufacturing Technology Institute(Grant No.KZ571801)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.2020kfyXJJS088)the Young Elite Scientists Sponsorship Program by CAST(Grant No.YESS20200381).
文摘Triply periodic minimal surfaces(TPMS)are structures with smooth surfaces and excellent energy absorption properties.Combining new functional materials,such as shape memory alloys,with TPMS structures provides a novel and promising research field.In this study,three TPMS structures(Gyroid,Diamond,and Primitive)of Cu-11.85Al-3.2Mn-0.1Ti alloy were printed by laser powder bed fusion,which is favorable for the fabrication of complex structures.The manufacturing fidelity,mechanical response,and superelastic properties of the three structures were investigated.Stress distributions in the three structures during compression were analyzed by finite element(FE)simulation.The three structures were equipped with high-quality,glossy surfaces and uniform pores.However,due to powder adhesion and forming steps,there were volumetric errors and dimensional deviations between the samples and the CAD models.The errors were within 1.6%for the Gyroid and Diamond structures.The dimensional deviations at the nodes in the three structures were less than 0.09 mm.The microstructures of all structures wereβ1´martensite,consistent with the cubic sample.Experimental results of compression showed that the structures underwent a layer-by-layer compression failure mode,and the Primitive structures exhibited a more pronounced oscillatory process.The Diamond structures showed the highest first fracture stress and strain of 164.67 MPa and 13.89%,respectively.It also possessed the lowest yield strength(61.97 MPa)and the best energy absorption properties(7.6 MJ/m3).Through the deformation analysis,the Gyroid and Diamond structures were found to fracture at a 45°direction,while the Primitive structures fractured horizontally.These findings were consistent with the results obtained from the FE simulation,which showed equivalent stress distributions.After applying various pre-strains,the Diamond structures displayed the highest superelastic strain of up to 3.53%.The superelastic recovery of all samples ranged from 63.5%to 71.5%.
文摘目的分析2000—2022年逍遥散研究现状,并预测其发展趋势,为该复方的进一步研究提供借鉴。方法利用中国学术期刊全文数据库(CNKI)和Web of Science(WoS)核心集数据库,检索逍遥散相关文献,使用CiteSpace软件对发文量趋势、作者、机构、关键词等进行可视化分析。结果经数据清洗,得到中文文献956篇,英文文献225篇;自2000年以来,逍遥散发文量呈逐年上升趋势;陈家旭(北京中医药大学)、秦雪梅(山西大学)、曾南(成都中医药大学)是该领域发文量前3的作者,其所在单位同样为主要研究机构;中文文献主要集中在抑郁症、乳腺癌及月经不调等方面,英文文献主要聚焦在抑郁症方面;近年来逍遥散研究热点逐渐由乳腺癌、月经不调、黄褐斑等向抗抑郁领域发展,其抗抑郁症机制主要集中在单胺类神经递质、神经内分泌、神经营养因子、能量代谢、肠道菌群、免疫等方面。但是,目前在逍遥散抗抑郁研究方面存在一些复方应用层面的问题,包括药味组成比例不统一、用药剂量范围过大、单味药是否炮制以及提取方法各有不同等,这将造成所制备的提取物存在较大差异,因此所引起的药效及其作用机制可能也有所不同,这些问题制约了其长远发展。结论逍遥散的研究正处于快速发展阶段,临床应用及实验研究方面已有大量积累,但因抑郁症发病机制复杂,逍遥散抗抑郁机制方面的研究仍需继续深入,如利用同位素示踪代谢组学、肠道微生物组学、单细胞转录组学等对其能量代谢、菌群调节和免疫调控的作用机制进行深入研究,为逍遥散的抗抑郁研究带来突破性创新。
文摘The main objective of this study is to optimize the fresh and strength properties of reactive powder concrete incorporated with industrial by-products like ultra-fine ground granulated blast furnace slag as cement substitute and added with coal bottom ash and recycled concrete fines as partial replacement of quartz sand by response surface methodology through design of experiment approach.Totally four responses namely slump,compressive strength(C-28),flexural strength(F-28),and split-tensile strength(S-28)after 28 days of curing period were considered.The statistical study on the reactive powder concrete includes the modeling of regression,normal probability plots,surface plot analysis,and optimization of process variables.The regression models of the considered responses(slump,C-28,F-28,and S-28)were tested.The results obtained from the analysis of variance(ANOVA)and Pareto chart were used to determine the statistical significance of the process variables.The influence of the variables on the responses was studied by means of the surface plot analysis.The optimal proportion of the variables against the responses was obtained through optimization response.The resulted regression equations were in the form of second-order polynomial equation and the prediction of strength properties was found to be in line with the experimental results.The difference of proportion of variance indicated that only 0.43%,6.42%,5.15%,and 9.7%of deviations cannot be expressed by the analysis.The ANOVA and Pareto charts represented the high significance and appropriateness of the linear term of slump response and the two-way interaction term of strength responses.The results of the optimization response revealed the optimal proportions of recycled concrete fines and coal bottom ash as 19.15%and 7.02%,respectively.
