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A review of anomalous refractive and reflective metasurfaces
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作者 Siqi Liu zhenyu ma +7 位作者 Jian Pei Qingbin Jiao Lin Yang Wei Zhang Hui Li Yuhang Li Yubo Zou Xin Tan 《Nanotechnology and Precision Engineering》 CAS CSCD 2022年第2期54-64,共11页
Abnormal refraction and reflection refers to the phenomenon in which light does not follow its traditional laws of propagation and instead is subject to refraction and reflection at abnormal angles that satisfy a gene... Abnormal refraction and reflection refers to the phenomenon in which light does not follow its traditional laws of propagation and instead is subject to refraction and reflection at abnormal angles that satisfy a generalization of Snell’s law.Metasurfaces can realize this phenomenon through appropriate selection of materials and structural design,and they have a wide range of potential applications in the military,communications,scientific,and biomedical fields.This paper summarizes the current state of research on abnormal refractive and reflective metasurfaces and their application scenarios.It discusses types of abnormal refractive and reflective metasurfaces based on their tuning modes(active and passive),their applications in different wavelength bands,and their future development.The technical obstacles that arise with existing metasurface technology are summarized,and prospects for future development and applications of abnormal refractive and reflective metasurfaces are discussed. 展开更多
关键词 Anomalous refraction and reflection Generalized Snell’s law Metasurface material Metalens
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Investigation on the temperature-dependent diffusion growth of intermetallic compounds in the Mg-Al-Zn system:Experiment and modeling
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作者 Kaiming Cheng Yan Zheng +12 位作者 Jiaxing Sun Yafei Zhao Jin Wang Huan Yu Dongqing Zhao Hang Li Jixue Zhou zhenyu ma Junmin Wang Cuiping Guo Xitao Wang Lijun Zhang Yong Du 《Journal of Magnesium and Alloys》 SCIE EI CAS 2024年第8期3394-3408,共15页
With the rapid development of Mg alloys,deeper understanding to the thermodynamic and diffusional kinetic behavior of intermetallic compounds(IMCs)is important for studying the effect of alloying elements to the micro... With the rapid development of Mg alloys,deeper understanding to the thermodynamic and diffusional kinetic behavior of intermetallic compounds(IMCs)is important for studying the effect of alloying elements to the microstructure evolution.Specially,a systematic quantitative investigation on the diffusional growth of IMCs is of great necessity.However,the works studying the elemental diffusion behaviors of multiple-element IMCs are rare in magnesium alloy systems.The current work takes the ternary Mg-Al-Zn system as research target,and combines the diffusion couple technique,phase stability diagrams,in-situ observation technique and numerical inverse method to investigate the temperature-dependent kinetic coefficients.The parabolic growth constant(PGC)and interdiffusion coefficients for Mg solid-solution phase andγ-Mg_(17)Al_(12),β-Mg_(2)Al_(3),ε-Mg_(23)Al_(30),MgZn_(2),Mg_(2)Zn_(3),τ-Mg_(32)(Zn,Al)49 andφ-Mg_(5)Zn_(2)Al_(2) IMCs in the Mg-Al-Zn alloy system are determined.By comparing the current experimental with calculation results,the rate-controlling factor of the temperature-dependent diffusion growth ofφ,τandεternary IMCs in the Mg-Al-Zn system is further discussed in detail. 展开更多
关键词 Diffusion couple Phase stability diagram Numerical inverse method(NIM) Interface migration High-temperature laser-scanning confocal microscopy(HTLSCM)
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境内“税收洼地”引发的避税问题及应对策略 被引量:8
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作者 张秋林 马振宇 +1 位作者 刘爽 杨诗 《国际税收》 CSSCI 北大核心 2021年第11期53-56,共4页
随着经济全球化的不断发展,企业集团规模日趋庞大、数量急剧增多。如何让跨区域经营的企业集团遵循利润应在经济活动发生地和价值创造地征税的原则成为各国研究的重要课题。许多学者与税务部门将目光集中在跨国企业集团的利润分配与税... 随着经济全球化的不断发展,企业集团规模日趋庞大、数量急剧增多。如何让跨区域经营的企业集团遵循利润应在经济活动发生地和价值创造地征税的原则成为各国研究的重要课题。许多学者与税务部门将目光集中在跨国企业集团的利润分配与税权的所属上,而对境内关联企业之间通过“税收洼地”进行利润转移的避税行为关注相对较少。本文结合《关于进一步深化税收征管改革的意见》的要求,研究企业集团利用境内“税收洼地”进行避税的现状和方式,分析问题产生的原因,从严格税收优惠政策和财政奖励政策的制定和管理、多渠道加强反避税管理、加大打击避税力度和加快反避税人才培养四个方面提出建议。 展开更多
关键词 税收洼地 避税 反避税 税收征管
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Severity of early allograft dysfunction following donation after circulatory death liver transplantation:a multicentre study 被引量:6
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作者 Kun Wang Di Lu +15 位作者 Yuhui Liu Wangyao Li Li Zhuang zhenyu ma Qinfen Xie Binhua Pan Yichao Wu Junli Chen Lidan Lin Xiaowen Feng Qiang Wei Xuyong Wei Haiyang Xie Zhengxin Wang Shusen Zheng Xiao Xu 《Hepatobiliary Surgery and Nutrition》 SCIE 2021年第1期9-19,共11页
Background:Early allograft dysfunction(EAD)is associated with decreased graft and patient survival rates.This study aimed to identify the severity of EAD and develop a predictive model for EAD after donation after cir... Background:Early allograft dysfunction(EAD)is associated with decreased graft and patient survival rates.This study aimed to identify the severity of EAD and develop a predictive model for EAD after donation after circulatory death(DCD)liver transplantation(LT).Furthermore,the influence of operative time on EAD incidence was also evaluated.Methods:In this retrospective,multicentre cohort study,nomograms were established based on a single-centre training cohort(n=321)and validated in a 3-center validation cohort(n=501).Results:The incidence rate of EAD was 46.4%(149/321)in the training cohort and 40.5%(203/501)in the validation cohort.Of the 149 EAD patients in the training cohort,77 patients with either elevated alanine aminotransferase(ALT)or aspartate aminotransferase(AST)were classified as having EAD type A,and the rest of the EAD patients were classified as having EAD type B.Recipients with EAD type B had lower graft and patient survival rates than recipients with EAD type A(P=0.043 and 0.044,respectively).We further developed a nomogram to predict EAD(graft weight,cold ischemia time,donor age,model for end-stage liver disease(MELD)score)and another nomogram to predict EAD type B(graft weight,cold ischemia time,MELD score).The nomograms for the prediction of EAD and EAD type B had good discrimination[concordance index(C-index)=0.712(0.666-0.758),0.707(0.641-0.773)]and calibration[Hosmer-Lemeshow(HL)P=0.384,P=0.425]in the validation cohort.An increased operative time(>6 h)was associated with increased EAD and EAD type B incidence in the high-risk group(P=0.005,P=0.020,respectively).Conclusions:EAD type B was associated with decreased graft and patient survival rates.The novel nomograms effectively predicted the incidence of EAD and EAD type B in DCD LT patients. 展开更多
关键词 Liver transplantation donation after circulatory death early allograft dysfunction(EAD)
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