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L曲线方法在地基红外高光谱反演温度廓线中的应用

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光谱学与光谱分析 2016年第11期36卷 3620-3624页

作者：黄威刘磊高太长李书磊胡帅解放军理工大学气象海洋学院江苏南京211101

利用地基红外高光谱辐射数据可以反演得到高时间分辨率的边界层大气温度廓线。目前的AERIoe最优化反演算法相比于传统的＂剥洋葱＂算法有较大的改进,且对初值的依赖程度较低。但AERIoe算法中正则化算子的选择对反演结果的稳定性和反演... 详细信息

利用地基红外高光谱辐射数据可以反演得到高时间分辨率的边界层大气温度廓线。目前的AERIoe最优化反演算法相比于传统的＂剥洋葱＂算法有较大的改进,且对初值的依赖程度较低。但AERIoe算法中正则化算子的选择对反演结果的稳定性和反演时间有重要影响。目前主要采用经验的方法选择正则化算子,迭代步数较多,耗费大量的计算时间。提出了利用L曲线方法代替经验法选取正则化算子的改进方案,以提高AERIoe方法的反演速度。改进后的算法通过绘制解范数和残余范数的二维曲线图,取其拐点作为最优的正则化参数,相比于传统的经验法有着更好的理论基础。采用2011年美国大气辐射测量计划中SGP站点的晴空大气红外辐射数据进行反演实验。结果表明,利用该方法得到的反演结果具有很好的稳定性、收敛性和精度。相比于经验的方法,利用L曲线方法获得的正则化算子反演温度廓线时的收敛速度更快,迭代步数较少,可以节约大量的计算时间;在反演精度方面,L曲线方法在边界层中上层的反演精度更高,1~3km高度上温度廓线的RMSE值提高了大约0.2K。

关键词：最优估计反演方法 L曲线正则化算子高光谱

Paleoclimate data assimilation: Principles and prospects

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Science China Earth Sciences 2025年

作者： Haoxun ZHANG Mingsong li Yongyun hu Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of PhysicsPeking University Institute of Ocean Research Peking University

Reconstructing climate states during geological periods is a key focus in studying Earth system evolution. Substantial progress has been achieved in reconstructing paleoclimate and paleoenvironment using both Earth system models and paleoclimate proxies. However, current paleoclimate reconstructions face several challenges:the accuracy of Earth system model simulations relies on model parameter settings. Paleoclimate proxy data exhibit significant variability across different periods and regions, and proxy data are often sparse, hindering the accuracy and global relevance of proxy-based *** the pros and cons of these methods, paleoclimate data assimilation can effectively integrate Earth system models and paleoclimate proxy data, enhancing the precision and global relevance of reconstructions. Using approaches such as the ensemble Kalman filter as an example, this paper introduces the principles of paleoclimate data assimilation and reviews recent advancements in reconstructing paleoclimate states using these techniques. Paleoclimate data assimilation offers new insights and advanced techniques for paleoclimate reconstruction, with potential applications extending to the entire Cenozoic, Mesozoic, and even Paleozoic eras. These applications could deepen our understanding of the past climatic backgrounds of extreme climate events such as glacial-interglacial cycles, hyperthermals, and oceanic anoxic events, providing a reference for predicting future climate change.

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不同机架角时多叶准直器叶片对不同调强放疗剂量影响

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中华放射肿瘤学杂志 2011年第4期20卷 345-347页

作者：阮长利徐利明宋启斌马广栋李长虎武汉大学人民医院肿瘤中心 430060

目的研究加速器多叶准直器角度为0°和不同机架角时多叶准直器叶片对不同调强放疗剂量的影响。方法用30cm×30cm×3cm固体水模体预选静态调强和动态调强中大小合适的30个单方向野和机架角为0°、45°、90°、270°、315°，用Mapcheck... 详细信息

目的研究加速器多叶准直器角度为0°和不同机架角时多叶准直器叶片对不同调强放疗剂量的影响。方法用30cm×30cm×3cm固体水模体预选静态调强和动态调强中大小合适的30个单方向野和机架角为0°、45°、90°、270°、315°，用Mapcheck二维半导体矩阵测量和其剂量分析系统的γ分析方法（3％／3mm、5％／3mm）对相应通过率进行定量分析。以治疗靶区由小到大预选30例患者的静态调强和动态调强计划用上述同样方法测量和分析。结果加速器多叶准直器角度为0。和机架角分别为0°、45°、90°、270°、315°时静态调强和动态调强30个单方向野实测的3％／3mm平均通过率分别为97．71％和96．25％（t=1．70，P=0．389）、96．34％和93．72％（t=2．95，P=0．002）、96．65％和92．98％（t=2．87，P=0．005）、95．87％和93．15％（t=2．71，P=0．006）、96．09％和93．51％（t=2．89，P=0．004），5％／3mm的平均通过率也无差别，分别为99．31％～99．73％和98．89—99．68％（t=0．57～1．90，P=0．913—0．725）；30例患者计划的3％／3mm平均通过率分别为96．11％～96．76％和94．88～95．78％（t=1．02—1．61，P=0．317～0．235）。结论当加速器多叶准直器角度为0°和不同机架角度时多叶准直器叶片对调强放疗剂量相比0°时确有影响，但其面剂量分布误差都在可接受的5％内。

关键词：调强放射疗法多叶准直器机架角

Direct Photolithography of WO_(x)Nanoparticles for High‑Resolution Non‑Emissive Displays

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Nano-Micro Letters 2025年第3期17卷 297-309页

作者： chang Gu Guojian Yang Wenxuan Wang Aiyan Shi Wenjuan Fang Lei Qian Xiaofei hu Ting Zhang Chaoyu Xiang Yu‑Mo Zhang Laboratory of Optoelectronic Information Technology and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Hangzhou Bay Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315336People’s Republic of China Smart Materials for Architecture Research Lab Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China State Key Lab of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012People’s Republic of China

High-resolution non-emissive displays based on electrochromic tungsten oxides(WOx)are crucial for future near-eye virtual/augmented reality interactions,given their impressive attributes such as high environmental stability,ideal outdoor readability,and low energy ***,the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron ***,we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand *** strategy enabled us to achieve ultra-high resolution efficiently(line widthlity(>3600 cycles),as well as promising applications in electronic logos,pixelated displays,flexible electronics,*** success and advancements presented here are expected to inspire and accelerate research and development(R&D)in high-resolution non-emissive displays and other ultra-fine micro-electronics.

关键词： Electrochromic Direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays

Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑life lithium Metal Batteries

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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang li Wen‑Xia Su Jia‑Min hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑Peng Cai Kang li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous li deposition and highly reversible li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous li+flux lithium metal battery

High-precision tip positioning composite feedforward control of linear colocated motion systems with Bi-Loop iterative feedforward tuning

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Science China Technological Sciences 2025年

作者： Junyu hu Yourui TAO Shanhu li Xu HAN College of Mechanical and Vehicle Engineering Hunan University State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology

To enhance the tip positioning accuracy and robustness against disturbances of linear colocated motion systems, a novel composite feedforward (COMFF) control with Bi-Loop iterative feedforward tuning (IFFT) is proposed. The tip positioning error consists of the coupled tip residual vibration and linear motor tracking error. Given the influence of nonlinear friction and load flexibility, the topology of COMFF is designed as decoupled structures so that COMFF can suppress the tip residual vibration and compensate for the linear motor tracking error compatibly. Furthermore, Bi-Loop IFFT is built to improve the robustness of COMFF in high-precision motor tracking performance. In the state space of the linear motor tracking error based on the projection theorem, two loops are performed in parallel along the iteration direction. One is the P-type iteration loop that drives linear motor tracking errors to converge to the zero state. The other is the observation loop constructed by the recursive least square with forgetting factors to accelerate the P-type iteration loop. Driven by the P-type iteration loop with the aid of the observation loop, the proposed COMFF is integrated with fast convergence and high robustness when confronted with model disturbances. The effectiveness of the proposed COMFF combined with Bi-Loop IFFT is validated by experiments.

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Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1749-1763页

作者： Tian Qin Yuxin Jin Yiming Qin Feifei Yuan Hongbin Lu Jianzhong hu Yong Cao Chengjun li Department of Spine Surgery and Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Sports Medicine Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

关键词： corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury syringin TRIB2

Bifunctional bridging capping layer enables 24.5% efficiency of perovskite solar cells with polymer-based hole transport materials

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Science China Chemistry 2025年第1期68卷 350-359页

作者： Can Zhu Yiyang Wang Lei Meng Beibei Qiu Jing li Shucheng Qin Ke hu Xin Jiang Wenbin Lai Minchao liu Zhe liu Chenxing Lu Jinyuan Zhang Yongfang li Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences School of Chemical Science University of Chinese Academy of Sciences Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province College of Physics and Electronic Information Engineering Zhejiang Normal University Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of Sciences Laboratory of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials ScienceSoochow University

Developing a bridge capping layer between perovskite and hole transport layer materials（HTMs） in the n-i-p perovskite solar cells（pero-SCs） is an effective approach to modify the morphology of HTMs and passivate the perovskite ***, we select the quinoxaline-based bifunctional passivation agent, quinoxalin-6-yl-methylamine hydrochloride（Qx MACl）,as the bridging layer, and a D-A copolymer PBQ12 containing the same quinoxaline unit as an HTM for the n-i-p pero-SCs. Due to the π-π stacking among the common quinoxaline units in the bridge layer and HTM, Qx MACl induces the π-π stacking of the PBQ12 film and improves the film morphology of HTMs with better conductivity. Additionally, Qx MACl can effectively passivate the perovskite surface, and PBQ12 possesses appropriate energy levels and high hole mobility. The pero-SCs based on FAPbI3with PBQ12/Qx MACl treatment showed a higher power conversion efficiency（PCE） of 24.05% and outstanding stability, maintaining 95.4% and 92.1% of its initial PCE after 750 h of storage and after over 800 h of thermal annealing at 85 °C, respectively. To further enhance the PCE of the PBQ12/Qx MACl-based devices, we developed a non-metal ion dopant for the PBQ12 HTM. Through trace doping of PBQ12 HTM by the non-metal ion dopant, the PCE of the PBQ12/Qx MACl-based devices reached 25.24%（the calibrated PCE of 24.55% by the National Institute of Metrology, China）.

关键词： D-A copolymer, hole transport materials, bifunctional bridge capping layer, passivation perovskite solar cells

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公路桥梁设计中的耐久性问题及解决方案研究

工程与建设 2024年第2期38卷 316-318页

作者：李昌虎安徽省建筑科学研究设计院安徽合肥230088

在公路桥梁设计项目中,桥梁的耐久性是保证其长期稳定和安全运行的关键因素。随着交通负荷的不断增加和环境条件的复杂多变,如何提高公路桥梁的耐久性成了设计和施工过程中的一项重要挑战。本文从公路桥梁设计的角度出发,深入探讨了影... 详细信息

在公路桥梁设计项目中,桥梁的耐久性是保证其长期稳定和安全运行的关键因素。随着交通负荷的不断增加和环境条件的复杂多变,如何提高公路桥梁的耐久性成了设计和施工过程中的一项重要挑战。本文从公路桥梁设计的角度出发,深入探讨了影响桥梁耐久性的主要问题,包括混凝土碳化、钢筋腐蚀以及冻融损伤等,分析了这些问题对桥梁结构安全性的威胁。同时,文章还介绍了一系列创新技术和解决方案,旨在提升公路桥梁工程的耐久性。本研究不仅为桥梁工程设计提供了理论依据和技术支持,也为今后桥梁的维护和管理提供了参考。

关键词：公路桥梁设计耐久性问题解决方案