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法布里-珀罗干涉仪在远程探测领域的应用

光谱学与光谱分析 2024年第7期44卷 1801-1812页

作者：金康张楠刘冰南开大学电子信息与光学工程学院现代光学研究所天津300350 火箭军特色医学中心疾病预防控制科北京100088

远程光谱探测是人类探索大尺寸空间和物质的重要手段,在天文、气象、深海等领域发挥着重要的作用,但收集远程光谱对光谱仪的性能也提出了很高的要求。根据Jacquinot提出的光谱性能评价标准,相较于其他光谱系统(光栅光谱仪,棱镜光谱仪等)... 详细信息

远程光谱探测是人类探索大尺寸空间和物质的重要手段,在天文、气象、深海等领域发挥着重要的作用,但收集远程光谱对光谱仪的性能也提出了很高的要求。根据Jacquinot提出的光谱性能评价标准,相较于其他光谱系统(光栅光谱仪,棱镜光谱仪等),法布里-珀罗(F-P)干涉仪通光孔径大、多光束干涉的光谱分辨能力强,使其在远程弱光探测领域有着天然的优势。从1914年法布里本人第一次将F-P干涉仪用于天文观测以来,F-P干涉仪已被广泛应用于远程光谱测量领域,并逐渐发展出各种改进型F-P干涉仪。传统F-P干涉仪在远程探测领域主要面临三个问题:自由光谱范围窄,大孔径的F-P干涉仪装调难度大,环状干涉结构能量分散。随着探测需求的不断提升和科学技术的长足进步,解决方案也应运而生,本文介绍了三种典型的改进型F-P干涉仪,分别是:增加自由光谱范围的级联F-P干涉仪,适用于极端环境下的旋转扫描F-P干涉仪以及将能量分散的干涉圆环转换为能量集中的干涉直线的F-P干涉系统(CLIO)。对F-P干涉仪在气象、天文、深海等领域中的重要应用进行了系统的总结。在气象学领域,介绍了用于大气中层和热层风速测量的大口径F-P干涉仪,测量大气中的痕量气体及其同位素体的德国海森堡高精细度F-P干涉仪;在天文学领域,介绍了由美国威斯康星大学设计、用于研究星际物质发射线的级联F-P干涉仪;在海洋学领域,介绍了国内F-P干涉仪测量布里渊散射的主要应用实例:2004年北京师范大学设计的水下布里渊散射系统,2021年上海交通大学设计的星载布里渊散射系统等;在大气污染检测领域,介绍了南开大学设计的F-P干涉仪用于测量飞秒激光远程光丝NaCl气溶胶荧光光谱。最后提出光谱识别精度,热稳定性是未来F-P干涉仪应用在远程光谱测量领域需要进一步突破的难点。

关键词：法布里-珀罗干涉仪远距离弱信号探测天文学气象学海洋学

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Protein Arginine Methyltransferase 1 Ablation in Motor Neurons Causes Mitochondrial Dysfunction Leading to Age-related Motor Neuron Degeneration with Muscle Loss

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Research 2024年第1期2023卷 637-649页

作者： Hyun-Kyung So Hyebeen Kim jinwoo Lee Chang-Lim You Chae-Eun Yun Hyeon-Ju Jeong Eun-Ju jin Yunju Jo Dongryeol Ryu Gyu-Un Bae Jong-Sun kang Department of Molecular Cell Biology Sungkyunkwan University School of MedicineSuwonKorea Single Cell Network Research Center Sungkyunkwan University School of MedicineSuwonKorea Research Institute of Aging-Related Diseases AniMusCureInc.SuwonKorea Drug Information Research Institute Muscle Physiome Research CenterCollege of PharmacySookmyung Women’s UniversitySeoulKorea

Neuromuscular dysfunction is tightly associated with muscle wasting that occurs with age or due to degenerative ***,the molecular mechanisms underlying neuromuscular dysfunction are currently *** studies have proposed important roles of Protein arginine methyltransferase 1(Prmt1)in muscle stem cell function and muscle *** the current study,we set out to determine the role of Prmt1 in neuromuscular function by generating mice with motor neuron-specific ablation of Prmt1(mnKO)using *** exhibited age-related motor neuron degeneration and neuromuscular dysfunction leading to premature muscle loss and ***1 deficiency also impaired motor function recovery and muscle reinnervation after sciatic nerve *** transcriptome analysis of aged mnKO lumbar spinal cords revealed alterations in genes related to inflammation,cell death,oxidative stress,and ***,mnKO lumbar spinal cords of sciatic nerve injury model or aged mice exhibited elevated cellular stress response in motor ***,Prmt1 inhibition in motor neurons elicited mitochondrial *** findings demonstrate that Prmt1 ablation in motor neurons causes agerelated motor neuron degeneration attributing to muscle ***,Prmt1 is a potential target for the prevention or intervention of sarcopenia and neuromuscular dysfunction related to aging.

关键词： degeneration impaired prevention

Semi-analytical Solutions for Wellbores with Graded Skin Zones in Poroelastic Media

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Acta Mechanica Solida Sinica 2024年第3期37卷 385-395页

作者： Zhiqiang Fan Zhihe jin School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering University of MaineOronoME04469USA

In analyzing the complex interaction between the wellbore and the reservoir formation,the hydromechanical properties of the region proximal to the wellbore,referred to as the“wellbore skin zone”,play a pivotal role in determining flow dynamics and the resulting formation *** models of the wellbore skin zone generally assume a constant permeability throughout,resulting in a sharp permeability discontinuity at the skin-reservoir *** paper introduces a model for a wellbore with a continuously graded skin zone of finite thickness within a poroelastic *** solutions are derived using the Laplace transform method,addressing both positive and negative skin *** results are presented to illustrate the effects of graded permeability/skin zone thickness on pore pressures and stresses around a *** results highlight a distinct divergence in stress and pore pressure fields when comparing wellbores with negative skin zones to those with positive skin zones or no skin at all.

关键词： Poroelastic Graded permeability Analytical solution Wellbore Skin zone

Advanced Algorithm for Parameters Estimation of Negative Binomial Distribution with High Dimensional Sparse Group Structure

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Journal of Systems Science & Complexity 2024年第5期37卷 2173-2195页

作者： LI Meiqi jin Baisuo School of Management University of Science and Technology of China

Negative binomial regression is a powerful technique for modeling count data, particularly when dealing with overdispersion. However, estimating the parameters for large-dimensional sparse models is challenging due to the complexity of optimizing the mean and dispersion parameter of the negative binomial distribution. To address this issue, the authors propose a novel approach that employs two iterations of the majorize-minimize(MM) algorithm, one for estimating the dispersion parameter and the other for estimating the mean parameters. These approaches improve the convergence speed and stability of the algorithm. The authors also use group penalty for variable selection, which enhances the accuracy and efficiency of the algorithm. The proposed method provides an explicit solution,simplifies the iteration process, and maintains good stability while ensuring algorithm ***, the authors apply the proposed algorithm to the zero-inflated model and demonstrate its promising predictive performance on specific data sets. The research has important implications for count data modeling and analysis in various fields, such as data mining, machine learning, and bioinformatics.

关键词： Group structure majorize-minimize (MM) negative binomial

Enhanced identification and localization of metabolites in Scutellariae Radix using ion mobility enabled MALDI-Q-TOF/MS imaging

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Journal of Pharmaceutical Analysis 2024年第2期14卷 284-286页

作者： Lixing Nie Lieyan Huang Xiaofei Jia Shuai kang Lingwen Yao Yanpei Wu Hao Yuan Yongli Liu Feng Wei Hongyu jin Xiang Li Shuangcheng Ma National Institutes for Food and Drug Control Beijing102629China Chinese Academy of Medical Science and Peking Union Medical College Beijing100006China Waters Corporation Beijing102600China Hebei Institute for Drug and Medical Device Control Shijiazhuang050227China Department of Pharmacy Medical Supplies Center of the PLA General HospitalBeijing100853China

Unraveling the distribution of metabolites in traditional Chinese medicine(TCM)provides direct indications for understanding their regulatory and functional basis,which is of paramount significance for better utilization and quality control of medicinal plants[1].Recently,imaging techniques such as near-infrared spectroscopy,Raman spectroscopy,and mass spectrometry(MS)were explored to reveal the spatial context of component accumulation and localization[2,3].

关键词： medicine(TCM) Radix Scutellaria

Trifunctional robust electrocatalysts based on 3D Fe/N-doped carbon nanocubes encapsulating Co4N nanoparticles for efficient battery-powered water electrolyzers

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Carbon Energy 2024年第6期6卷 124-139页

作者： Hyung Wook Choi Hongdae Lee Jun Lu Seok Bin Kwon Dong In Jeong Beum jin Park Jiwon Kim Bong Kyun kang Gun Jang Dae Ho Yoon Ho Seok Park SKKU Advanced Institute of Nano Technology(SAINT) Sungkyunkwan UniversitySuwon-siGyeonggi-doRepublic of Korea School of Chemical Engineering Sungkyunkwan UniversitySuwon-siGyeonggi-doRepublic of Korea School of Advanced Materials Science and Engineering Sungkyunkwan UniversitySuwon-siGyeonggi-doRepublic of Korea Department of Electronic Materials Devicesand Equipment EngineeringSoonchunhyang UniversityAsan CityChungnamRepublic of Korea SKKU Institute of Energy Science and Technology(SIEST) Sungkyunkwan UniversitySuwon-siGyeonggi-doRepublic of Korea Department of Health Sciences and Technology Samsung Advanced Institute for Health Sciences and Technology(SAIHST)Sungkyunkwan UniversitySuwonRepublic of Korea

Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize hierarchically structured Co_(4)N@Fe/N-C for rechargeable zinc-air batteries and overall water-splitting *** confirmed by theoretical and experimental results,the high intrinsic oxygen reduction reaction,oxygen evolution reaction,and hydrogen evolution reaction activities of Co_(4)N@Fe/N-C were attributed to the formation of the heterointerface and the modulated local electronic ***,Co_(4)N@Fe/N-C induced improvement in these trifunctional electrocatalytic activities owing to the hierarchical hollow nanocube structure,uniform distribution of Co_(4)N,and conductive encapsulation by Fe/***,the rechargeable zinc-air battery with Co_(4)N@Fe/N-C delivers a high specific capacity of 789.9 mAh g^(-1) and stable voltage profiles over 500 ***,the overall water electrolyzer with Co_(4)N@Fe/N-C achieved better durability and rate performance than that with the Pt/C and IrO2 catalysts,delivering a high Faradaic efficiency of 96.4%.Along with the great potential of the integrated water electrolyzer powered by a zinc-air battery for practical applications,therefore,the mechanistic understanding and active site identification provide valuable insights into the rational design of advanced multifunctional electrocatalysts for energy storage and conversion.

关键词： battery-powered electrolyzers hierarchical structure Prussian blue analog trifunctional electrocatalyst zinc-air battery

Confluence of asymmetric catalysis and electrosynthesis in sustainable chemical transformations

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Science China Chemistry 2024年第3期67卷 755-758页

作者： Qinglin Zhang kang Liang Chang Guo Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China

Electrosynthesis has gained widespread recognition for its extraordinary ability to precisely control the redox *** outstanding capability enables the direct conversion of non-functionalized substrates into reactive intermediates by utilizing easily accessible starting materials, eliminating the need for preliminary functionalization procedures and allowing for unconventional bond activations.

关键词： Confluence of asymmetric catalysis and electrosynthesis in sustainable chemical transformations

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Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

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Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles Michael Albert kang Chiang Liew Faculty of Tropical Forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building *** fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and *** article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their *** current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this ***,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also *** points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification

Jackknife Model Averaging for Composite Quantile Regression

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Journal of Systems Science & Complexity 2024年第4期37卷 1604-1637页

作者： YOU kang WANG Miaomiao ZOU Guohua School of Mathematical Sciences Capital Normal UniversityBeijing 100089China School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100105China

In this paper,the authors propose a frequentist model averaging method for composite quantile regression with diverging number of *** from the traditional model averaging for quantile regression which considers only a single quantile,the proposed model averaging estimator is based on multiple *** well-known delete-one cross-validation or jackknife approach is applied to estimate the model *** resultant jackknife model averaging estimator is shown to be asymptotically optimal in terms of minimizing the out-of-sample composite final prediction *** studies are conducted to demonstrate the finite sample performance of the new model averaging *** proposed method is also applied to the analysis of the stock returns data and the wage data.

关键词： Asymptotic optimality composite quantile regression cross-validation model averaging

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