The construction of intermetallic compounds(IMCs)connection layers with special compositions by adding small amounts of alloying elements has been proven to be an effective strategy for improving the reliability of el...The construction of intermetallic compounds(IMCs)connection layers with special compositions by adding small amounts of alloying elements has been proven to be an effective strategy for improving the reliability of electronic component interconnect.However,the synergistic effect mechanism of multi-component alloy compositions on the growth behavior of IMCs is not clear.Herein,we successfully prepared a new quaternary alloy solder with a composition of Sn-0.7Cu-0.175Pt-0.025Al(wt%)using the high-throughput screening(HTS)method.The results showed that it possesses excellent welding performance with an inhibition rate over 40%on the growth of IMCs layers.For Cu_(6)Sn_(5),the co-doping of Al and Pt not only greatly improves its thermodynamic stability,but also effectively suppresses the phase transition.Meanwhile,the co-doping of Al and Pt also significantly delays the generation time of Kirkendall defects.The substitution sites of Al and Pt in Cu_(6)Sn_(5)have been explored using atomic resolution imaging and advanced data informatics,indicating that Al and Pt preferentially substitute Sn and Cu atoms,respectively,to generate(Cu,Pt)_(6)(Sn,Al)_(5).A one-dimensional(1D)kinetic model of the IMCs layer growth at the Sn solder/Cu substrate interface was derived and validated,and the results showed that the error of the derived mathematical model is less than 5%.Finally,the synergistic mechanism of Al and Pt co-doping on the growth rate of Cu_(6)Sn_(5)was further elucidated.This work provides a feasible route for the design and development of multi-component alloy solders.展开更多
The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the mor...The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the morphology of the intermetallic compound(IMC)precipitated at the interface were observed.Results show that DC has a significant effect on the wettability and IMC.As the current increases,the balance wetting force and the thickness of the IMC layer increase.The direction of the DC also has a certain effect on the balance wetting force and IMC layer.When the current is negative,the final balance wetting force and the thickness of the Cu_(6)Sn_(5) layer are significantly higher than those in the positive current case,which is attributed to electromigration.The IMC precipitation at the interface provides a chemical driving force for the movement of the triple junction.The interaction of the interface atoms and the chemical reaction are enhanced by DC,thereby improving wettability.Meanwhile,the Marangoni convection caused by DC inside liquid Sn solder changes the structure of triple junction,which provides a physical driving force for the spread of the liquid Sn solder on the Cu substrate.展开更多
本文以现象级综艺《花儿与少年·丝路季》为研究对象,基于整合营销传播(IMC)理论框架,系统解构其如何通过“三位一体”营销模型实现国家战略的青春化转译。节目借助内容整合,将“丝绸之路”蕴含的文化传播话语体系,通过娱乐化转译...本文以现象级综艺《花儿与少年·丝路季》为研究对象,基于整合营销传播(IMC)理论框架,系统解构其如何通过“三位一体”营销模型实现国家战略的青春化转译。节目借助内容整合,将“丝绸之路”蕴含的文化传播话语体系,通过娱乐化转译方式进行创新性呈现,通过“游学探访”展现文化交融,创新品牌植入并构建多模态内容矩阵;在渠道整合上,利用“台网协同 + 社交裂变 + 海外适配”实现触点管理效能最大化;在利益整合方面,构建官方、品牌、用户三方协同的价值生态,实现多元主体价值共创。节目通过“接触点共振”搭建四级传播链路,取得了多维度的传播效能,成为现象级爆款综艺,实现流量裂变、品牌增值,在文化传播、社会责任履行和国际传播等方面成果显著。其成功实践验证了IMC理论在主流文化传播中的有效性,为真人秀节目文化出海提供了新思路。This paper takes the phenomenal variety show “Divas Hit the Road Season V” as the research object, and based on the theoretical framework of integrated marketing communication (IMC), systematically deconstructs how it realizes the youthful translation of the national strategy through the “Trinity” marketing model. Through content integration, creatively presenting the cultural communication discourse system embedded in the “the Silk Road” through entertaining translation, demonstrates cultural integration through “study tours”, creates innovative brand implantation and builds a multimodal content matrix. In terms of channel integration, the program utilizes “collaboration between Television and the Internet + social fission + overseas adaptation” to maximize the effectiveness of contact point management;in terms of benefit integration, the program builds a value ecosystem with the synergy of the official, brands, and users to realize the value co-creation of multiple subjects. By building a four-level communication chain through “contact point resonance”, the program has achieved multi-dimensional communication efficacy, become a phenomenal hit variety show, realized traffic fission and brand value-added, and achieved remarkable results in cultural communication, social responsibility fulfillment and international communication. Its successful practice verifies the effectiveness of IMC theory in mainstream cultural communication and provides new ideas for reality TV programs to go overseas.展开更多
We report the structural,mechanical and electromagnetic properties of the intermetallic compound Mn_(23)C_(6).The bulk Mn_(23)C_(6)sample was synthesized using high temperature high pressure quenching method(HTHPQM),a...We report the structural,mechanical and electromagnetic properties of the intermetallic compound Mn_(23)C_(6).The bulk Mn_(23)C_(6)sample was synthesized using high temperature high pressure quenching method(HTHPQM),and investigated in detail by x-ray diffraction,electron microscope,magnetization and electrical resistivity measurements,etc.First-principles calculation based on density functional theory ab intio simulation was carried out to calculate the bonding and electromagnetic properties of Mn_(23)C_(6).Based on our experimental and simulated results,the Mn_(23)C_(6)in this work is single phase of a faced-centered cubic structure with space group Fm-3m(No.225).Determined by SEM and TEM,the bulk sample consists of monocrystal Mn_(23)C_(6)crystals with 2-15μm grain sizes,it is the quick quenching method in the synthesizing process that brings such small crystal grain size.Archimedes method gives its density of 7.14 g/cm^(3),95.74%of its theoretically calculated density 7.458 g/cm^(3).Owing to the abundant Mn 3d electrons and a framework of strongly linked Mn atoms in Mn_(23)C_(6),the electrical conductivity is up to 8.47×10^(-4)Ω·m,which shows that Mn_(23)C_(6)is a good conductor.Our magnetic susceptibility analyses reveal a magnetization peak in the M-T curve at 104 K,combined with the M-H curve and Curie-Weiss law,this peak usually means the transformation between paramagnetic and antiferromagnetic orders.To gain an insight into the mechanism of the magnetic phase transition,we calculated the magnetic properties,and the results show that different from normal antiferromagnetic order,the magnetic orders in Mn_(23)C_(6)consist of three parts,the direct ferromagnetic and antiferromagnetic exchange coupling interactions between Mn atoms,and the indirect antiferromagnetic super-exchange interaction between Mn and C atoms.Therefore,we reveal that the Mn_(23)C_(6)is a complex magnetic competition system including different magnetic orders and interactions,instead of the normal long-range antiferromagnetic order.展开更多
基金financially supported by the Innovation Team Cultivation Project of Yunnan Province(No.202005AE160016)the Key Research&Development Program of Yunnan Province(No.202103AA080017)Yunnan Ten Thousand Talents Plan Young&Elite Talents Project(No.YNWR-QNBJ2018-044)。
文摘The construction of intermetallic compounds(IMCs)connection layers with special compositions by adding small amounts of alloying elements has been proven to be an effective strategy for improving the reliability of electronic component interconnect.However,the synergistic effect mechanism of multi-component alloy compositions on the growth behavior of IMCs is not clear.Herein,we successfully prepared a new quaternary alloy solder with a composition of Sn-0.7Cu-0.175Pt-0.025Al(wt%)using the high-throughput screening(HTS)method.The results showed that it possesses excellent welding performance with an inhibition rate over 40%on the growth of IMCs layers.For Cu_(6)Sn_(5),the co-doping of Al and Pt not only greatly improves its thermodynamic stability,but also effectively suppresses the phase transition.Meanwhile,the co-doping of Al and Pt also significantly delays the generation time of Kirkendall defects.The substitution sites of Al and Pt in Cu_(6)Sn_(5)have been explored using atomic resolution imaging and advanced data informatics,indicating that Al and Pt preferentially substitute Sn and Cu atoms,respectively,to generate(Cu,Pt)_(6)(Sn,Al)_(5).A one-dimensional(1D)kinetic model of the IMCs layer growth at the Sn solder/Cu substrate interface was derived and validated,and the results showed that the error of the derived mathematical model is less than 5%.Finally,the synergistic mechanism of Al and Pt co-doping on the growth rate of Cu_(6)Sn_(5)was further elucidated.This work provides a feasible route for the design and development of multi-component alloy solders.
基金Doctoral Research Start-up Fund of Lanzhou University of Arts and Science(2021-9)Innovation Fund for Colleges and Universities of Gansu Province,China(2022B-265)。
文摘The wetting behavior of liquid tin(Sn)solder on copper(Cu)substrate at 250℃was investigated by the wetting balance method under the action of direct current(DC).The curves of wetting balance were measured and the morphology of the intermetallic compound(IMC)precipitated at the interface were observed.Results show that DC has a significant effect on the wettability and IMC.As the current increases,the balance wetting force and the thickness of the IMC layer increase.The direction of the DC also has a certain effect on the balance wetting force and IMC layer.When the current is negative,the final balance wetting force and the thickness of the Cu_(6)Sn_(5) layer are significantly higher than those in the positive current case,which is attributed to electromigration.The IMC precipitation at the interface provides a chemical driving force for the movement of the triple junction.The interaction of the interface atoms and the chemical reaction are enhanced by DC,thereby improving wettability.Meanwhile,the Marangoni convection caused by DC inside liquid Sn solder changes the structure of triple junction,which provides a physical driving force for the spread of the liquid Sn solder on the Cu substrate.
文摘本文以现象级综艺《花儿与少年·丝路季》为研究对象,基于整合营销传播(IMC)理论框架,系统解构其如何通过“三位一体”营销模型实现国家战略的青春化转译。节目借助内容整合,将“丝绸之路”蕴含的文化传播话语体系,通过娱乐化转译方式进行创新性呈现,通过“游学探访”展现文化交融,创新品牌植入并构建多模态内容矩阵;在渠道整合上,利用“台网协同 + 社交裂变 + 海外适配”实现触点管理效能最大化;在利益整合方面,构建官方、品牌、用户三方协同的价值生态,实现多元主体价值共创。节目通过“接触点共振”搭建四级传播链路,取得了多维度的传播效能,成为现象级爆款综艺,实现流量裂变、品牌增值,在文化传播、社会责任履行和国际传播等方面成果显著。其成功实践验证了IMC理论在主流文化传播中的有效性,为真人秀节目文化出海提供了新思路。This paper takes the phenomenal variety show “Divas Hit the Road Season V” as the research object, and based on the theoretical framework of integrated marketing communication (IMC), systematically deconstructs how it realizes the youthful translation of the national strategy through the “Trinity” marketing model. Through content integration, creatively presenting the cultural communication discourse system embedded in the “the Silk Road” through entertaining translation, demonstrates cultural integration through “study tours”, creates innovative brand implantation and builds a multimodal content matrix. In terms of channel integration, the program utilizes “collaboration between Television and the Internet + social fission + overseas adaptation” to maximize the effectiveness of contact point management;in terms of benefit integration, the program builds a value ecosystem with the synergy of the official, brands, and users to realize the value co-creation of multiple subjects. By building a four-level communication chain through “contact point resonance”, the program has achieved multi-dimensional communication efficacy, become a phenomenal hit variety show, realized traffic fission and brand value-added, and achieved remarkable results in cultural communication, social responsibility fulfillment and international communication. Its successful practice verifies the effectiveness of IMC theory in mainstream cultural communication and provides new ideas for reality TV programs to go overseas.
文摘We report the structural,mechanical and electromagnetic properties of the intermetallic compound Mn_(23)C_(6).The bulk Mn_(23)C_(6)sample was synthesized using high temperature high pressure quenching method(HTHPQM),and investigated in detail by x-ray diffraction,electron microscope,magnetization and electrical resistivity measurements,etc.First-principles calculation based on density functional theory ab intio simulation was carried out to calculate the bonding and electromagnetic properties of Mn_(23)C_(6).Based on our experimental and simulated results,the Mn_(23)C_(6)in this work is single phase of a faced-centered cubic structure with space group Fm-3m(No.225).Determined by SEM and TEM,the bulk sample consists of monocrystal Mn_(23)C_(6)crystals with 2-15μm grain sizes,it is the quick quenching method in the synthesizing process that brings such small crystal grain size.Archimedes method gives its density of 7.14 g/cm^(3),95.74%of its theoretically calculated density 7.458 g/cm^(3).Owing to the abundant Mn 3d electrons and a framework of strongly linked Mn atoms in Mn_(23)C_(6),the electrical conductivity is up to 8.47×10^(-4)Ω·m,which shows that Mn_(23)C_(6)is a good conductor.Our magnetic susceptibility analyses reveal a magnetization peak in the M-T curve at 104 K,combined with the M-H curve and Curie-Weiss law,this peak usually means the transformation between paramagnetic and antiferromagnetic orders.To gain an insight into the mechanism of the magnetic phase transition,we calculated the magnetic properties,and the results show that different from normal antiferromagnetic order,the magnetic orders in Mn_(23)C_(6)consist of three parts,the direct ferromagnetic and antiferromagnetic exchange coupling interactions between Mn atoms,and the indirect antiferromagnetic super-exchange interaction between Mn and C atoms.Therefore,we reveal that the Mn_(23)C_(6)is a complex magnetic competition system including different magnetic orders and interactions,instead of the normal long-range antiferromagnetic order.
