Metal matrix self-lubricating materials lie at the core of cutting-edge aerospace,mechanical,and electrical industries,which demand technological performances that cannot be met by traditional liquid lubricants.Rapid ...Metal matrix self-lubricating materials lie at the core of cutting-edge aerospace,mechanical,and electrical industries,which demand technological performances that cannot be met by traditional liquid lubricants.Rapid innovation in nanocarbon materials in recent years enabled rapid development of advanced nanocomposites for applications in structural engineering and functional devices.Carbonous materials(e.g.,graphite,graphene and carbon nanotubes),exhibit a wide range of unique electrical,mechanical,and thermal properties,which are also considered ideal lubricating reinforcements for metal matrix nanocomposites(MMCs)with superior mechanical and tribological properties.In this review,we first showcase the distinctive features of the constituents commonly employed in self-lubricating MMCs,encompassing the high-strength metallic matrix and nano-carbonous reinforcement.Then,we present a comprehensive overview of the recent advancements in preparation techniques for these advanced MMCs,followed by an in-depth discussion on their corresponding tribological properties and wear mechanisms.We close this review by outlining key problems to be solved and the future trend of the development in self-lubricating MMCs.展开更多
The excellent properties of metallic glass(MG)films make them perfect candidates for the use in miniature systems and tools.However,their high coefficients of friction(COFs)and poor wear resistance considerably limit ...The excellent properties of metallic glass(MG)films make them perfect candidates for the use in miniature systems and tools.However,their high coefficients of friction(COFs)and poor wear resistance considerably limit their long-term performance in nanoscale contact.We report the fabrication of a MG/graphene multilayer by the repeated deposition of Cu_(50)Zr_(50) MG with alternating layers of graphene.The microstructure of the multilayer was characterized by the transmission electron microscopy(TEM).Its mechanical and nanotribological properties were studied by nanoindentation and nanoscratch tests,respectively.A molecular dynamics(MD)simulation revealed that the addition of graphene endowed the MG with superelastic recovery,which reduced friction during nanoscratching.In comparison with the monolithic MG film,the multilayer exhibited improved wear resistance and a low COF in repeated nanowear tests owing to the enhanced mechanical properties and lubricating effect caused by the graphene layer.This work is expected to motivate the design of other novel MG films with excellent nanowear properties for engineering applications.展开更多
Ovarian endometrioma(OE),also known as“chocolate cysts,”is a cystic mass that develops in the ovaries due to endometriosis and is a common gynecological condition characterized by the growth of endometrial tissue ou...Ovarian endometrioma(OE),also known as“chocolate cysts,”is a cystic mass that develops in the ovaries due to endometriosis and is a common gynecological condition characterized by the growth of endometrial tissue outside the uterus,leading to symptoms such as dysmenorrhea,pelvic pain,and infertility.However,the precise molecular and cellular mechanisms driving this pathophysiology remain largely unknown,posing challenges for diagnosis and treatment.Here,we employed integrated single-cell transcriptomic profiling of over 52,000 individual cells from endometrial tissues of OE patients and healthy donors and identified twelve major cell populations.We identified notable alterations in cell type-specific proportions and molecular signatures associated with OE.Notably,the activation of IGFBP5^(+) macrophages with pro-inflammatory properties,NK cell exhaustion,and aberrant proliferation of IQCG^(+) and KLF2^(+) epithelium are key features and may be the potential mechanisms underlying the pathogenesis of OE.Collectively,our data contribute to a better understanding of OE at the single cell level and may pave the way for the development of novel therapeutic strategies.展开更多
基金support by the National Key Research and Development Program of China(2022YFB3809000)the Natural Science Foundation of China(No.52175188)+2 种基金Key Research and Development Program of Shaanxi Province(2023-YBGY-434)the Open Fund of Liaoning Provincial Key Laboratory of Aero-engine Materials Tribology(Grant No.LKLAMTF202301)State Key Laboratory for Mechanical Behavior of Materials(20222412).
文摘Metal matrix self-lubricating materials lie at the core of cutting-edge aerospace,mechanical,and electrical industries,which demand technological performances that cannot be met by traditional liquid lubricants.Rapid innovation in nanocarbon materials in recent years enabled rapid development of advanced nanocomposites for applications in structural engineering and functional devices.Carbonous materials(e.g.,graphite,graphene and carbon nanotubes),exhibit a wide range of unique electrical,mechanical,and thermal properties,which are also considered ideal lubricating reinforcements for metal matrix nanocomposites(MMCs)with superior mechanical and tribological properties.In this review,we first showcase the distinctive features of the constituents commonly employed in self-lubricating MMCs,encompassing the high-strength metallic matrix and nano-carbonous reinforcement.Then,we present a comprehensive overview of the recent advancements in preparation techniques for these advanced MMCs,followed by an in-depth discussion on their corresponding tribological properties and wear mechanisms.We close this review by outlining key problems to be solved and the future trend of the development in self-lubricating MMCs.
基金The authors would like to thank the National Natural Science Foundation of China(No.51801161)Guangdong Basic and Applied Basic Research Foundation,China(No.2021A1515010756)+1 种基金the Natural Science Foundation of Jiangsu Province,China(No.BK20180266)the Fundamental Research Funds for the Central Universities(No.3102019JC001).
文摘The excellent properties of metallic glass(MG)films make them perfect candidates for the use in miniature systems and tools.However,their high coefficients of friction(COFs)and poor wear resistance considerably limit their long-term performance in nanoscale contact.We report the fabrication of a MG/graphene multilayer by the repeated deposition of Cu_(50)Zr_(50) MG with alternating layers of graphene.The microstructure of the multilayer was characterized by the transmission electron microscopy(TEM).Its mechanical and nanotribological properties were studied by nanoindentation and nanoscratch tests,respectively.A molecular dynamics(MD)simulation revealed that the addition of graphene endowed the MG with superelastic recovery,which reduced friction during nanoscratching.In comparison with the monolithic MG film,the multilayer exhibited improved wear resistance and a low COF in repeated nanowear tests owing to the enhanced mechanical properties and lubricating effect caused by the graphene layer.This work is expected to motivate the design of other novel MG films with excellent nanowear properties for engineering applications.
基金supported from Scientific and Technological Innovation Project of China Academy of Chinese Medical Sciences(CI2023D003,CI2021B014)the National Key Research and Development Program of China(2022YFC2303600,2020YFA0908000)+8 种基金the Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTD-C-202002)the CACMS Innovation Fund(CI2023E002,CI2021A05101,CI2021A05104)the Science and Technology Foundation o f Shenzhen(JCYJ20210324115800001)the Science and Technology Foundation of Shenzhen(Shenzhen Clinical Medical Research Center for Geriatric Diseases)the Shenzhen Medical Research Fund(B2302051)the National Natural Science Foundation of China(82201786)Guangdong Basic and Applied Basic Research Foundation(2021A1515110646)Guangdong-Dongguan Joint Fund Regional Cultivation Project(2021B1515140033)Dongguan Science and Technology of Social Development Program(20211800904742,20221800905732,20221800904462).
文摘Ovarian endometrioma(OE),also known as“chocolate cysts,”is a cystic mass that develops in the ovaries due to endometriosis and is a common gynecological condition characterized by the growth of endometrial tissue outside the uterus,leading to symptoms such as dysmenorrhea,pelvic pain,and infertility.However,the precise molecular and cellular mechanisms driving this pathophysiology remain largely unknown,posing challenges for diagnosis and treatment.Here,we employed integrated single-cell transcriptomic profiling of over 52,000 individual cells from endometrial tissues of OE patients and healthy donors and identified twelve major cell populations.We identified notable alterations in cell type-specific proportions and molecular signatures associated with OE.Notably,the activation of IGFBP5^(+) macrophages with pro-inflammatory properties,NK cell exhaustion,and aberrant proliferation of IQCG^(+) and KLF2^(+) epithelium are key features and may be the potential mechanisms underlying the pathogenesis of OE.Collectively,our data contribute to a better understanding of OE at the single cell level and may pave the way for the development of novel therapeutic strategies.
