Metal halide perovskites have recently emerged as promising candidates for the next generation of X-ray detectors due to their excellent optoelectronic properties.Especially,two-dimensional(2D)perovskites afford many ...Metal halide perovskites have recently emerged as promising candidates for the next generation of X-ray detectors due to their excellent optoelectronic properties.Especially,two-dimensional(2D)perovskites afford many distinct properties,including remarkable structural diversity,high generation energy,and balanced large exciton binding energy.With the advantages of 2D materials and perovskites,it successfully reduces the decomposition and phase transition of perovskite and effectively suppresses ion migration.Meanwhile,the existence of a high hydrophobic spacer can block water molecules,thus making 2D perovskite obtain excellent stability.All of these advantages have attracted much attention in the field of X-ray detection.This review introduces the classification of 2D halide perovskites,summarizes the synthesis technology and performance characteristics of 2D perovskite X-ray direct detector,and briefly discusses the application of 2D perovskite in scintillators.Finally,this review also emphasizes the key challenges faced by 2D perovskite X-ray detectors in practical application and presents our views on its future development.展开更多
Core decompression(CD)with the elimination of osteonecrotic bone is the most common strategy for treating early-stage nontraumatic osteonecrosis of the femoral head(ONFH).Adjuvant treatments are widely used in combina...Core decompression(CD)with the elimination of osteonecrotic bone is the most common strategy for treating early-stage nontraumatic osteonecrosis of the femoral head(ONFH).Adjuvant treatments are widely used in combination with CD as suitable methods of therapy.Existing augmentations have to be fabricated in advance.Here,we report a novel injectable glycerin-modified polycaprolactone(GPCL)that can adapt to the shape of the CD cavity.GPCL shows great flowability at 52.6℃.After solidification,its compressive modulus was 120 kPa at body temperature(37℃).This excellent characteristic enables the polymer to provide mechanical support in vivo.In addition,GPCL acts as a carrier of the therapeutic agent zoledronic acid(ZA),demonstrating sustained release into the CD region.ZA-loaded GPCL was injected into ONFH lesions to treat early-stage nontraumatic cases.Compared to that in the CD group,CD+ZA-loaded GPCL injection preserved bone density and increased the collagen level in the femoral head.At the interface between the GPCL and CD tunnel wall,osteogenesis was significantly promoted.In addition,morphological evaluations revealed that the femoral heads in the CD+ZA-GPCL group exhibited improved pressure resistance.These results suggest a strategy effective to preserve the bone density of the femoral head,thus decreasing the possibility of femoral head collapse.This novel injectable polymer has,therefore,considerable potential in clinical applications.展开更多
Copper-based metal halides have become important materials in the feld of X-ray and photodetection due to their excellent optical properties,good environmental stability and low toxicity.This review presents the progr...Copper-based metal halides have become important materials in the feld of X-ray and photodetection due to their excellent optical properties,good environmental stability and low toxicity.This review presents the progress of research on crystal structure/morphology,photophysics/optical properties and applications of copper-based metal halides.We also discuss the challenges of copper-based metal halides with a perspective of their future research directions.展开更多
The power conversion efficiency(PCE)of perovskite solar cells(PSCs)has increased rapidly to 25.7%in 2022.There is growing curiosity about whether it will increase further up to the PCE limit.Understanding the fundamen...The power conversion efficiency(PCE)of perovskite solar cells(PSCs)has increased rapidly to 25.7%in 2022.There is growing curiosity about whether it will increase further up to the PCE limit.Understanding the fundamental energy loss mechanism and targeted treatment is the crux to step forward,especially the definite and management of photons in PSCs.Here,we first briefly review the main modes of photon energy loss in PSCs and illustrate the significance of photon recycling.Next,historical research trials to overcome these loss mechanisms in PSCs are highlighted,including the application of anti-reflection coatings,plasmonic strategies,and the adoption of upconversion and downconversion materials.Finally,we make a brief summary and prospect about strategies that can help to improve photon management in the future.展开更多
基金This work was funded by the National Natural Science Foundation of China(22279049 and 12247101)the Fundamental Research Funds for the Central Universities(lzujbky-2021-it31,lzujbky-2021-ct15 and lzujbky-2021-sp69)+1 种基金the calculation work was supported by Supercomputing Center of Lanzhou Universitythe Gansu Province Outstanding Doctoral Student Program(22JR5RA435).
文摘Metal halide perovskites have recently emerged as promising candidates for the next generation of X-ray detectors due to their excellent optoelectronic properties.Especially,two-dimensional(2D)perovskites afford many distinct properties,including remarkable structural diversity,high generation energy,and balanced large exciton binding energy.With the advantages of 2D materials and perovskites,it successfully reduces the decomposition and phase transition of perovskite and effectively suppresses ion migration.Meanwhile,the existence of a high hydrophobic spacer can block water molecules,thus making 2D perovskite obtain excellent stability.All of these advantages have attracted much attention in the field of X-ray detection.This review introduces the classification of 2D halide perovskites,summarizes the synthesis technology and performance characteristics of 2D perovskite X-ray direct detector,and briefly discusses the application of 2D perovskite in scintillators.Finally,this review also emphasizes the key challenges faced by 2D perovskite X-ray detectors in practical application and presents our views on its future development.
基金supported by the National Natural Science Foundation of China(NSFC:81672173,82072448)the Key Research Development Program of Shaanxi Province(2018ZDCXL-SF-28-7)。
文摘Core decompression(CD)with the elimination of osteonecrotic bone is the most common strategy for treating early-stage nontraumatic osteonecrosis of the femoral head(ONFH).Adjuvant treatments are widely used in combination with CD as suitable methods of therapy.Existing augmentations have to be fabricated in advance.Here,we report a novel injectable glycerin-modified polycaprolactone(GPCL)that can adapt to the shape of the CD cavity.GPCL shows great flowability at 52.6℃.After solidification,its compressive modulus was 120 kPa at body temperature(37℃).This excellent characteristic enables the polymer to provide mechanical support in vivo.In addition,GPCL acts as a carrier of the therapeutic agent zoledronic acid(ZA),demonstrating sustained release into the CD region.ZA-loaded GPCL was injected into ONFH lesions to treat early-stage nontraumatic cases.Compared to that in the CD group,CD+ZA-loaded GPCL injection preserved bone density and increased the collagen level in the femoral head.At the interface between the GPCL and CD tunnel wall,osteogenesis was significantly promoted.In addition,morphological evaluations revealed that the femoral heads in the CD+ZA-GPCL group exhibited improved pressure resistance.These results suggest a strategy effective to preserve the bone density of the femoral head,thus decreasing the possibility of femoral head collapse.This novel injectable polymer has,therefore,considerable potential in clinical applications.
基金supported by the National Natural Science Foundation of China(52073131,51902148,and 12047501)the Fundamental Research Funds for the Central Universities(lzujbky-2021-it31,lzujbky-2021-59,lzujbky-2021-ct15,lzujbky2021-ct01,and lzujbky-2021-sp69)supported by Supercomputing Center of Lanzhou University。
基金Acknowledgements The authors wish to express their appreciations to the anonymous referees. Their suggestions have greatly improved this paper. They are also grateful to Prof. Congming Li for many fruitful discussion. The first author was supported by the National Natural Science Foundation of China （Grant No. 11171158）, the Natural Science Foundation of Jiangsu （No. BK2012846）, and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry.
文摘我们在 n 为加权的 Hardy-Littlewood-Sobolev 不平等的 Euler-Lagrange 系统的积极解决方案获得最佳的 integrability：$$\left\{\begin { 聚在一起 } u (x)=\frac { 1 }{{\left |x \right|^\alpha }}\int_{\mathbb { R }^ n }{\frac {{ v (y)^ q }}{{\left |y \right|^\beta \left |{ x - y }\right|^\lambda }}} dy， \hfill \\ v (x)=\frac { 1 }{{\left |x \right|^\beta }}\int_{\mathbb { R }^ n }{\frac {{ u (y)^ p }}{{\left |y \right|^\alpha \left |{ x - y }\right|^\lambda }}} dy。\hfill \\\end { 聚在一起 }\right.$$ C。Jin 和 C. 李[计算。Var。部分微分方程， 2006， 26：447457 ] 为整齐上升开发了某很有趣的方法并且为 p 获得了最佳的 integrability， q > 1。基于一些新观察，这里，我们在那里克服困难，并且为 p 的盒子导出最佳的 integrability， q 1 并且 pq 1。这 integrability 在估计积极答案的 asymptotic 行为起一个关键作用什么时候 | x |0 并且什么时候 | x | .
基金funded by the National Natural Science Foundation of China(Grant Nos.22279049 and 52073131)the Fundamental Research Funds for the Central Universities(Nos.lzujbky-2021-ct15 and lzujbky-2021-sp69).
文摘Copper-based metal halides have become important materials in the feld of X-ray and photodetection due to their excellent optical properties,good environmental stability and low toxicity.This review presents the progress of research on crystal structure/morphology,photophysics/optical properties and applications of copper-based metal halides.We also discuss the challenges of copper-based metal halides with a perspective of their future research directions.
基金funded by the National Natural Science Foundation of China(52073131)the Fundamental Research Funds for the Central Universities(lzujbky-2021-ct15).
文摘The power conversion efficiency(PCE)of perovskite solar cells(PSCs)has increased rapidly to 25.7%in 2022.There is growing curiosity about whether it will increase further up to the PCE limit.Understanding the fundamental energy loss mechanism and targeted treatment is the crux to step forward,especially the definite and management of photons in PSCs.Here,we first briefly review the main modes of photon energy loss in PSCs and illustrate the significance of photon recycling.Next,historical research trials to overcome these loss mechanisms in PSCs are highlighted,including the application of anti-reflection coatings,plasmonic strategies,and the adoption of upconversion and downconversion materials.Finally,we make a brief summary and prospect about strategies that can help to improve photon management in the future.
