The development of cost-effective titanium alloys with outstanding mechanical properties has always been a primary concern of the modern aerospace industry.However,the intrinsic sensitivity of theirαprecipitates to h...The development of cost-effective titanium alloys with outstanding mechanical properties has always been a primary concern of the modern aerospace industry.However,the intrinsic sensitivity of theirαprecipitates to heat treatments proliferates the manufacturing costs to achieve desirable strength and ductility,especially in engineering occasions.In current work,a silicide-containingα+βTi-5Al-7.5V-0.5Mo-0.5Zr-0.5Si(TC5751S)alloy has been evidenced to exhibit advanced mechanical properties with reduced sensitivity to heat treatments.It is noted that more nano-scale secondaryα(αs)precipitate with a simultaneous dissolution in micron-scale primaryα(αp)and(Ti,Zr)_(5)Si_(3)silicides in the current alloy as the solution temperature increases.However,this alloy shows excellent and stabilized strength-ductility synergy in all cases(ultimate tensile strength:1335±30 MPa,yield strength:1245±30 MPa,fracture strain:9.6%±0.5%)irrespective of the aforementioned variations in the microstructure.This stabilized strength and ductility of TC5751S are rationalized based on the compensation mechanisms be-tween the contributions from silicide and heterogeneousαprecipitates.The quantitative analysis unveils that the increased α_(s)/β phase boundary strengthening(σ_(PB))is approximately offset by the decrease in silicide strengthening(σ_(silicide))due to silicide dissolution with increasing solution temperatures,leading to the strength of TC5751S in a dynamic equilibrium state.Simultaneously,the dissolution of silicides re-duces the cracking tendency and complements the ductility loss due to α_(p) reduction and α_(s) precipitation,leading to the ductility insensitive to heat treatments.Therefore,the compensating role of silicides to the effects of heterogeneousαprecipitates on both the strength and ductility of titanium alloys has been well-verified in our work,providing a novel pathway to the development of high-performance titanium alloys friendly to processing strategies.展开更多
Tumor-targeted radiopharmaceuticals have become an attractive modality for tumor diagnosis and treatment in clinics.However;their wide clinical applications are seriously impeded by poor tumor targeting;rapid systemic...Tumor-targeted radiopharmaceuticals have become an attractive modality for tumor diagnosis and treatment in clinics.However;their wide clinical applications are seriously impeded by poor tumor targeting;rapid systemic clearance;and short tumor retention.Therefore;developing advanced radiopharmaceuticals with great tumor specificity and prolonged retention time is highly desirable for efficient tumor treatment.Herein;we report a tumor-targeted covalently anchoring strategy that selectively crosslinks the radiopharmaceuticals to intratumoral macromolecules for prolonged tumor theranostics.A covalent multi-targeted radiopharmaceutical(CMTR)d-IR-2(^(125)IRGD)that includes a sulfenic acid-reactive 1,3-cyclohexanedione group was developed.We demonstrated this probe could specifically accumulate at the tumor site and bind to the sulfenated proteins that are overexpressed within tumors;which greatly prevents the efflux of probes in tumor tissues while having faster clearance in healthy tissues resulting in 12 h longer tumor retention than conventional probes for sensitive NIR and SPECT/CT detection of tumors in vivo.More notably;the ^(131)I-labeled probe could significantly suppress the growth of lung tumor A549.We thus envision that this work may offer a promising approach to developing effective radiopharmaceuticals for precise diagnosis and treatment of various tumors.展开更多
基金supported by the National Key Research and Development Program of China(No.2021YFB3702604)the National Natural Science Foundation of China(No.52001258).
文摘The development of cost-effective titanium alloys with outstanding mechanical properties has always been a primary concern of the modern aerospace industry.However,the intrinsic sensitivity of theirαprecipitates to heat treatments proliferates the manufacturing costs to achieve desirable strength and ductility,especially in engineering occasions.In current work,a silicide-containingα+βTi-5Al-7.5V-0.5Mo-0.5Zr-0.5Si(TC5751S)alloy has been evidenced to exhibit advanced mechanical properties with reduced sensitivity to heat treatments.It is noted that more nano-scale secondaryα(αs)precipitate with a simultaneous dissolution in micron-scale primaryα(αp)and(Ti,Zr)_(5)Si_(3)silicides in the current alloy as the solution temperature increases.However,this alloy shows excellent and stabilized strength-ductility synergy in all cases(ultimate tensile strength:1335±30 MPa,yield strength:1245±30 MPa,fracture strain:9.6%±0.5%)irrespective of the aforementioned variations in the microstructure.This stabilized strength and ductility of TC5751S are rationalized based on the compensation mechanisms be-tween the contributions from silicide and heterogeneousαprecipitates.The quantitative analysis unveils that the increased α_(s)/β phase boundary strengthening(σ_(PB))is approximately offset by the decrease in silicide strengthening(σ_(silicide))due to silicide dissolution with increasing solution temperatures,leading to the strength of TC5751S in a dynamic equilibrium state.Simultaneously,the dissolution of silicides re-duces the cracking tendency and complements the ductility loss due to α_(p) reduction and α_(s) precipitation,leading to the ductility insensitive to heat treatments.Therefore,the compensating role of silicides to the effects of heterogeneousαprecipitates on both the strength and ductility of titanium alloys has been well-verified in our work,providing a novel pathway to the development of high-performance titanium alloys friendly to processing strategies.
基金supported by the National Natural Science Foundation of China(T2325019,22077092)the Basic Research Program of Jiangsu(BK20243030)+3 种基金the Special Project of“Technological Innovation”Project of CNNC Medical Industry Co.Ltd.(ZHYLYB2021001)the Four“Batches”Innovation Project of Invigorating Medical through Science and Technology of Shanxi Province(2022XM19)the Open Project Program of the State Key Laboratory of Radiation Medicine and Protection(GZK12024016,GZK12023050,GZK12024013)a Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Tumor-targeted radiopharmaceuticals have become an attractive modality for tumor diagnosis and treatment in clinics.However;their wide clinical applications are seriously impeded by poor tumor targeting;rapid systemic clearance;and short tumor retention.Therefore;developing advanced radiopharmaceuticals with great tumor specificity and prolonged retention time is highly desirable for efficient tumor treatment.Herein;we report a tumor-targeted covalently anchoring strategy that selectively crosslinks the radiopharmaceuticals to intratumoral macromolecules for prolonged tumor theranostics.A covalent multi-targeted radiopharmaceutical(CMTR)d-IR-2(^(125)IRGD)that includes a sulfenic acid-reactive 1,3-cyclohexanedione group was developed.We demonstrated this probe could specifically accumulate at the tumor site and bind to the sulfenated proteins that are overexpressed within tumors;which greatly prevents the efflux of probes in tumor tissues while having faster clearance in healthy tissues resulting in 12 h longer tumor retention than conventional probes for sensitive NIR and SPECT/CT detection of tumors in vivo.More notably;the ^(131)I-labeled probe could significantly suppress the growth of lung tumor A549.We thus envision that this work may offer a promising approach to developing effective radiopharmaceuticals for precise diagnosis and treatment of various tumors.
