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Chinese Journal of Chemistry 2024年第10期42卷 1128-1132页

作者： Chao Li Lei Chen Hongye Wang Zixi Yan Bin lyu Weiping lyu Changwei Jiang Dehua Lu Jiaxing Li Ning Jiao Song Song State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityXue Yuan Rd.38Beijing 100191China

A mild and practical method for synthesizing fluorinated quinoline derivatives,which have a wide range of applications in pharmaceuticals,materials,and organic synthesis,was described through C—F bond insertion into indoles using CHBr_(2)*** simple conditions,readily availability of CHBr_(2)F,as well as the versatility of the transformations make this strategy very powerful in synthesizing 3-fluoroquinoline and *** mechanistic studies reveal that bromofluorocarbene generated in-situ under basic condition was the key intermediate.

关键词： Skeleton edit Fluorocarbene Ring expansion Quinoline Quinolone

Learnable digital signal processing:a new benchmark of linearity compensation for optical fiber communications

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Light(Science & Applications) 2024年第9期13卷 1931-1943页

作者： Zekun Niu Hang Yang lyu Li Minghui Shi Guozhi Xu Weisheng Hu Lilin Yi State Key Lab of Advanced Optical Communication Systems and Networks School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240PR China

The surge in interest regarding the next generation of optical fiber transmission has stimulated the development of digital signal processing(DSP)schemes that are highly cost-effective with both high performance and low *** benchmarks for nonlinear compensation methods,however,traditional DSP designed with block-by-block modules for linear compensations,could exhibit residual linear effects after compensation,limiting the nonlinear compensation *** we propose a high-efficient design thought for DSP based on the learnable perspectivity,called learnable DSP(LDSP).LDSP reuses the traditional DSP modules,regarding the whole DSP as a deep learning framework and optimizing the DSP parameters adaptively based on backpropagation algorithm from a global *** method not only establishes new standards in linear DSP performance but also serves as a critical benchmark for nonlinear DSP *** comparison to traditional DSP with hyperparameter optimization,a notable enhancement of approximately 1.21 dB in the Q factor for 400 Gb/s signal after 1600 km fiber transmission is experimentally demonstrated by combining LDSP and perturbation-based nonlinear compensation *** from the learnable model,LDSP can learn the best configuration adaptively with low complexity,reducing dependence on initial *** proposed approach implements a symbol-rate DSP with a small bit error rate(BER)cost in exchange for a 48%complexity reduction compared to the conventional 2 samples/symbol *** believe that LDSP represents a new and highly efficient paradigm for DSP design,which is poised to attract considerable attention across various domains of optical communications.

关键词： fiber signal optical

Equalization Reconstruction Algorithm Based on Reference Signal Frequency Domain Block Joint for DTMB-Based Passive Radar

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Journal of Beijing Institute of Technology 2024年第1期33卷 41-53页

作者： Shuai Ma Zeqi Yang Hua Zhang Yiheng Liu Xiaode lyu Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China National Key Laboratory of Microwave Imaging Technology Beijing 100190China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China.

Channel equalization plays a pivotal role within the reconstruction phase of passive radar reference *** the context of reconstructing digital terrestrial multimedia broadcasting(DTMB)signals for low-slow-small(LSS)target detection,a novel frequency domain block joint equalization algorithm is presented in this *** the DTMB signal frame structure and channel multipath transmission characteristics,this article adopts a unconventional approach where the delay and frame structure of each DTMB signal frame are reconfigured to create a circular convolution block,facilitating concurrent fast Fourier transform(FFT)*** equalization,an inverse fast Fourier transform(IFFT)-based joint output and subsequent data reordering are executed to finalize the equalization process for the DTMB *** and measured data confirm that this algorithm outperforms conventional techniques by reducing signal errors rate and enhancing real-time *** passive radar LSS detection,it effectively suppresses multipath and noise through frequency domain equalization,reducing false alarms and improving the capabilities of weak target detection.

关键词： passive radar frequency domain equalization reference signal reconstruction digital terrestrial multimedia broadcasting(DTMB)

The Impact of New Regulations on Prevention and Control of E-Cigarettes on Adolescents in Middle Schools—A City in China,2022–2023

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China CDC weekly 2024年第14期6卷 289-293页

作者： Meng lyu Wenlong Lu Lanhua Zou Jingfan Xiong Jie Yang Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina Shenzhen Center for Chronic Disease Control Shenzhen CityGuangdong ProvinceChina

What is already known about this topic?To protect the health of young people from the harmful impacts of electronic cigarettes(e-cigarettes),China has enacted various policies and regulations since *** of October 1,2022,the Electronic Cigarette Management Measures were put into *** prohibited the sale of flavored e-cigarettes,permitting only those of plain tobacco flavor to be *** is added by this report?The illegal market for flavored e-cigarettes,often disguised as milk tea cups,cola cans,and violent bear images,continues to *** is an increased need to bolster support for the prohibition of flavored e-cigarettes and enhance public awareness of associated *** are the implications for public health practice?To advance the health of China’s youth,it is crucial to improve the implementation and understanding of ecigarette policies and guidelines.

关键词： Middle Impact plain

In-situ observation of structural evolution of single-atom catalysts:From synthesis to catalysis

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ChemPhysMater 2024年第1期3卷 24-35页

作者： Lei Wang Shuyuan lyu Shuohao Li School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China School of Art and Design Huaiyin Institute of TechnologyHuaian 223003China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China

Atomically dispersed single-atom catalysts(SACs)have been extensively studied over the past decade because of their high atom utilization efficiencies and specific *** numerous strategies have been proposed to obtain SACs with high densities and stabilities,the transformation mechanism that occurs during the reaction is still *** review summarizes the structural evolution of SACs in the preparation process and reaction with various electron microscopy techniques at atomic scale under environmental *** state-of-the-art environmental electron microscopy studies on SACs mainly focus on porous carbons,metals or metal oxides,and some specific composite *** dynamic evolution of SACs under various reaction conditions is also investigated in this ***,we highlight the challenges and drawbacks of the current studies and the prospects for the future exploration of SACs with environmental strategies.

关键词： Single-atom catalysts Structural transformation Atomization Environmental electron microscope

Determination of the critical rainfall of runoff-initiated debris flows by the perspective of physical mechanics and Shields stress

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Journal of Mountain Science 2024年第4期21卷 1160-1173页

作者： MA Chao ZHU Yongtai LU Lu DU Cui lyu Liqun DONG Jie School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Beijing Institute of Geological Hazard Prevention Beijing 100120China School of Software Engineering Chengdu University of Information TechnologyChengdu610225China Civil and Environmental Engineering Department Clarkson UniversityNY 13699USA

The critical rainfall of runoff-initiated debris flows is utmost importance for local early hazard *** paper presents research on the critical rainfall of runoff-initiated debris flows through comparisons between slope gradients and three key factors,including topographic contributing area,dimensionless discharge,and Shields *** rainfall amount was estimated by utilizing in-situ rainfall records and a slope-dependent Shields stress model was *** created model can predict critical Shields stress more accurately than the other two ***,a new dimensionless discharge equation was proposed based on the corresponding discharge-gradient *** new equation,along with factors such as contributing area above bed failure sites,channel width,and mean diameter of debris flow deposits,predicts a smaller rainfall amount than the in-situ measured *** the slope-dependent Shields stress model performs well and the estimated rainfall amount is lower than the in-situ records,the sediment initiation in the experiments falls within sheet flow regime due to a large Shields ***,further sediment initiation experiments at a steeper slope range are expected in the future to ensure that the sediment transport belongs to mass failure regime characterized by a low level of Shields ***,a more accurate hazard forecast on the runoff-initiated debris flow holds promise when the corresponding critical slope-dependent dimensionless discharge of no motion,fluvial sediment transport,mass flow regime,and sheet flow regime are considered.

关键词： Infinite slope stability Shields stress Contributing area-slope gradient Rainfall back estimation

A Novel Clutter Suppression Algorithm for Low-Slow-Small Targets Detecting Based on Sparse Adaptive Filtering

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Journal of Beijing Institute of Technology 2024年第1期33卷 54-64页

作者： Zeqi Yang Shuai Ma Ning Liu Kai Chang Xiaode lyu Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China National Key Laboratory of Microwave Imaging Technology Beijing 100190China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China Northern Institute of Electronic Equipment Beijing 100083China

Passive detection of low-slow-small(LSS)targets is easily interfered by direct signal and multipath clutter,and the traditional clutter suppression method has the contradiction between step size and convergence *** this paper,a frequency domain clutter suppression algorithm based on sparse adaptive filtering is *** pulse compression operation between the error signal and the input reference signal is added to the cost function as a sparsity constraint,and the criterion for filter weight updating is improved to obtain a purer echo *** the same time,the step size and penalty factor are brought into the adaptive iteration process,and the input data is used to drive the adaptive changes of parameters such as step *** proposed algorithm has a small amount of calculation,which improves the robustness to parameters such as step size,reduces the weight error of the filter and has a good clutter suppression performance.

关键词： passive radar interference suppression sparse representation adaptive filtering

Architecture Design of Protocol Controller Based on Traffic-Driven Software Defined Interconnection

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Chinese Journal of Electronics 2024年第2期33卷 362-370页

作者： Peijie LI Jianliang SHEN Ping lyu Chunlei DONG Ting CHEN Information Engineering University

To solve the problems of redundant logic resources and poor scalability in protocol controller circuits among communication networks, we propose a traffic-driven software defined interconnection(TSDI) *** unified software defined interconnection interface standards and the normalized interconnection topology are designed to implement the architecture of TSDI-based protocol controller. The key indicators of power, performance and area(PPA) can be realized while resolving the flexible interconnection of the controller. We designed a TSDI-based Rapid IO controller as an example. Compared to traditional designs, the design could achieve more protocol scalability,and Rapid IO protocol standards of Gen4 could be supported directly. The key PPA indicators, such as a lower delay of 56.1 ns and more than twice throughput of 98.1 Gbps, were achieved at the cost of a 23.4% area increase.

关键词： Protocols Software design Scalability Integrated circuit interconnections Process control Computer architecture Throughput

Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China

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Journal of Arid Land 2024年第6期16卷 798-815页

作者： LU Haitian ZHAO Ruifeng ZHAO Liu LIU Jiaxin lyu Binyang YANG Xinyue College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Gansu ProvinceLanzhou 730070China School of Geography Planning and Spatial SciencesUniversity of TasmaniaHobart TAS 7005Australia School of Chinese Language and Literature Xi'an International Studies UniversityXi'an 710128China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China School of Design and Built Environment Curtin UniversityPerth 6102Australia

Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid *** study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research *** on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water *** findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to *** surface water area exhibited significant fluctuations,while permanent surface water area showed a steady ***,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water *** change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human ***,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface *** of surface water resources faced by inland arid and semi-arid areas like Gansu Province are ***,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance *** study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity.

关键词： surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google Earth Engine climate change human activities inland arid and semi-arid areas

Efficacy of substances containing 3 types of active ingredients-saponins, flavones, and alkaloids in regulation of cytokines in autoimmune diseases a systematic review and Meta-analysis based on animal studies

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Journal of Traditional Chinese Medicine 2024年第3期44卷 417-426页

作者： ZHU Ruifang ZHANG Jun lyu Yaru CHEN Yulu HAN Shifan WANG Hongwei Key Laboratory for Molecular Diagnosis and Treatment of Hematologic Diseases Second Hospital of Shanxi Medical UniversityShanxi 030001China School of Nursing Shanxi Medical UniversityShanxi 030001China Editorial Office First Hospital of Shanxi Medical UniversityShanxi 030001China

OBJECTIVE: To investigate the efficacy of substances containing 3 types of active ingredients-saponins,flavones, and alkaloids on experimental animals with autoimmune diseases(AIDs).METHODS: The protocol for this systematic review and Meta-analysis was prospectively registered with PROSPERO(CRD42023395741). Searches were conducted in the China National Knowledge Infrastructure, Wanfang, Chinese Science and Technology Journals, China Biomedical, Pub Med,Cochrane Library, and Embase databases to screen for animal studies investigating the therapeutic effects of saponins, flavones, or alkaloids on autoimmune diseases;consequently, corresponding data extraction tables were prepared. Systematic Review Centre for Laboratory Animal Experimentation was used to assess the risk of methodological bias in the included literature. RevMan 5.4 was used for the Meta-analysis on the 8 serum ***: A total of 31 studies were included, all of which were randomized controlled studies. Meta-analysis indicated that substances rich in saponins, flavones, and alkaloids reduced serum levels of interleukin(IL)-1β[standardized mean difference(SMD) =-1.94, 95%confidence interval(CI)(-2.99,-0.90), P = 0.0003], IL-6 [SMD =-1.65, 95% CI(-2.33,-0.97,) P < 0.000 01],IL-17 [SMD =-2.41, 95% CI(-3.61,-1.20), P <0.0001], tumor necrosis factor(TNF)-α [SMD =-1.84, 95%CI(-2.61,-1.06), P < 0.0001], and interferon(IFN)-γ[SMD =-1.54, 95% CI(-2.43,-0.65), P = 0.0007], but increased serum levels of IL-4 [SMD = 1.30, 95% CI(0.15,2.44), P = 0.03) and IL-10 [SMD = 2.05, 95% CI(1.39,2.70), P < 0.000 01) in animal models. However, no significant regulatory effect of these three active components was observed on serum levels of IL-2 [SMD =-0.63, 95% CI(-1.82, 0.57), P = 0.30].CONCLUTIONS: Substances containing saponins,flavones, and alkaloids regulated the changes of immunerelated cytokines, it may be a novel dietary substance to relieve and control autoimmune diseases in the future.

关键词： autoimmune diseases saponins flavones alkaloids system evaluation Meta-analysis