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Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles

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Research in Astronomy and Astrophysics 2024年第3期24卷 194-204页

作者： Pei-Xin Luo Bao-lin {1. National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific ***,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly *** on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 1.4.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred *** on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction *** for solar cycle 25,its maximum ASN will be about1.6.7±33.40,obviously stronger than solar cycle *** peak year will occur approximately in 2024,and the period will be about 1.±1.*** for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 1.3.0±3.200,and period of about 1. yr.

关键词： Sun activity-Sun evolution-(Sun) sunspots-methods data analysis

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Chinese Journal of Electronics 2024年第3期33卷 683-693页

作者： Jiamei LIU lin {1. Hong XU PLA Strategic Support Force Information Engineering University

Deoxys-BC is the primitive tweakable block cipher of the Deoxys family of authenticated encryption *** on existing related-tweakey boomerang distinguishers,this paper improves the boomerang attacks on 1.-round Deoxys-BC-256 and 1.-round Deoxys-BC-384 by the optimized key guessing and the precomputation *** transfers a part of subtweakey guess in the key-recovery phase to the precomputation resulting in a significant reduction of the overall time *** 1.-round Deoxys-BC-256,we give a related-tweakey boomerang attack with time/data/memory complexities of 221..6/21.5.7/21.5.7,and give another attack with the less time complexity of221..8and memory complexity of 21.0 when the adversary has access to the full *** 1.-round Deoxys-BC-384,we give a related-tweakey boomerang attack with time/dat a/memory complexities of 2k-96+21.7.5/21.0.4/*** the key size k=256,it reduces the time complexity by a factor of 231.ompared with the previous 1.-round boomerang *** addition,we present two new related-tweakey boomerang distinguishers on 1.-round Deoxys-BC-384 with the same probability as the best previous distinguisher.

关键词： Ciphers Memory management Complexity theory Encryption Time complexity

Copper-catalyzed asymmetric dearomatizing amination of 2-naphthols:Csp^(2)–N coupling via 1.3-reductive elimination

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Science China Chemistry 2024年第8期67卷 2694-2700页

作者： Aying Yihuo Maoping Pu Zheng tan Jibang Liao Jiuqi tan Qi-lin Zhou Xiaohua Liu Xiaoming Feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Frontiers Science Centerfor New Organic MatterNankai UniversityTianjin300071China

An efficient catalytic asymmetric dearomatizing amination of 2-naphthols and phenols catalyzed by N,N′-dioxide-copper(I)complex as a chiral catalyst was presented.A variety of optically activeβ-naphthalenone compounds with a nitrogen-containing quaternary carbon stereocenter were obtained with high yield and enantioselectivity under mild reaction *** studies indicated that this Csp^(2)–N dearomatizing coupling proceeds via 1.3-reductive elimination of phenolate-Cu~Ⅲ-amino intermediate in five-membered ring transition *** origin of enantioselectivity has also been elucidated based on density functional theory calculations.

关键词： asymmetric catalysis amination dearomatization copper catalysis coupling reaction

Emergence of machine language: towards symbolic intelligence with neural networks

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National Science Review 2024年第4期11卷 27-30页

作者： Yuqi Wang Xu-Yao Zhang Cheng-lin Liu Tieniu {1. Zhaoxiang Zhang State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences

Representation learning is a core issue in artificial intelligence (AI). Currently,there exists a disparity in the choice of representation between humans and machines. Humans rely on discrete language for communicati...

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Copper-mediated assembly of SO_(2)F group via radical fluorine-atom transfer strategy

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Chinese Chemical Letters 2024年第9期35卷 4-5页

作者： Yu-Yu tan {1.-Heng He Wei-Min He School of Electrical Engineering University of South ChinaHengyang 421001China

Because of the unique reactivity of sulfonyl fluoride(SO_(2)F)group,such compound has found increasing applications in the areas of organic synthesis,new drug development,pesticide,material science and click chemistry,*** is of current interest to develop novel strategies and methods for the facile preparation of sulfonyl fluorides in a green and highly efficient manner[1.2].Although the traditional approach for the synthesis of sulfonyl fluorides relies on the nucleophilic substitution of fluoride atom with sulfonyl chlorides.

关键词： fluoride synthesis fluorine

Numerical modeling and experimental investigation of a two-phase sink vortex and its fluid-solid vibration characteristics

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 47-62页

作者： Zichao YIN Yesha NI lin LI Tong WANG Jiafeng WU Zhe LI Dapeng {1. College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310014China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China

A sink vortex is a common physical phenomenon in continuous casting,chemical extraction,water conservancy,and other industrial processes,and often causes damage and loss in ***,the real-time monitoring of the sink vortex state is important for improving industrial production ***,its suction-extraction phenomenon and shock vibration characteristics in the course of its formation are complex mechanical dynamic factors for flow field state *** address this issue,we set up a multi-physics model using the level set method(LSM)for a free sink vortex to study the two-phase interaction ***,a fluid–solid coup{1.g dynamic model was deduced to investigate the shock vibration characteristics and reveal the transition mechanism of the critical flow *** numerical results show that the coup{1.g energy shock induces a pressure oscillation phenomenon,which appears to be a transient enhancement of vibration at the vortex penetration *** central part of the transient enhancement signal is a high-frequency *** on the dynamic coup{1.g model,an experimental observation platform was established to verify the accuracy of the numerical *** water-model experiment results were accordant with the numerical *** above results provide a reference for fluid state recognition and active vortex control for industrial monitoring systems,such as those in aerospace pipe transport,hydropower generation,and microfluidic devices.

关键词： Free sink vortex Fluid-solid coupling Level set method(LSM) Multi-physics model Vibration characteristics

Low-energy-consumption temperature swing system for CO_(2) capture by combining passive radiative cooling and solar heating

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Green Energy & Environment 2024年第3期9卷 507-515页

作者： Ying-Xi Dang Peng tan Bin Hu Chen Gu Xiao-Qin Liu {1.-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is ***,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative *** desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for *** heating and cooling processes are completely driven by solar *** tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ***,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple *** present work may inspire the development of new temperature swing procedures with little energy consumption.

关键词： CO_(2)capture Solar heating Passive radiative cooling Temperature swing adsorption

Decision-making method for high-speed rail early warning system in complex earthquake situations

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Transportation Safety and Environment 2024年第3期6卷 47-61页

作者： Minjia tan Qizhou Hu Yikai Wu Juanjuan {1. Xin Fang School of Automation Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

To address the shortcomings in decision-making methods for ground motion threshold warning models in high-speed rail earthquake early warning systems(HSREEWs),we propose a dual judgement method and corresponding early warning process for earthquake early warning decisions based on joint peak ground acceleration(PGA)and complex earthquake environmental risk evaluation(ERE)***,we analyse the characteristics of four complex earthquake environments based on the characteristics of high-speed rail(HSR)operating ***,we establish an earthquake environmental risk evaluation index system and propose an adversarial interpretive structure modelling method-based complex earthquake situation evaluation model(AISM-based ESEM).The AISM method firstly evaluates the proximity by the TOPSIS(technique for order preference by similarity to an ideal solution)method,then effectively rank targets with fuzzy attributes through opposite hierarchical extraction rules without sacrificing system *** PGA can reflect the current size of earthquake energy,combining PGA thresholds with ESEM-derived values of ERE can effectively determine the risk status of each train and make decisions on the most appropriate alarm form and control measures for that ***,case analysis results under the background of Wenchuan Earthquake show that the new early warning decisionmaking method accurately assesses environmental risks in affected areas and provides corresponding warning levels as a supplement to existing HSREEWs warning models.

关键词： high-speed rail(HSR) earthquake situation earthquake risk decision-making earthquake early warning

Diabetes and high-glucose could upregulate the expression of receptor for activated C kinase 1.in retina

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World Journal of Diabetes 2024年第3期15卷 519-529页

作者： Jian tan Ang Xiao {1. Yang Yu-{1. Tao Yi Shao Qiong Zhou Department of Ophthalmology The First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual *** pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of *** for activated C kinase 1.RACK1.activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to ***,we hypothesize that the activation of RACK1.under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of *** To investigate the role and associated underlying mechanisms of RACK1.in the development of early *** In this study,Sprague-Dawley rats and adult RPE cell {1.e-1.(ARPE-1.)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1.in mediating PKC-εin early ***,the impact of RACK1.on apoptosis and barrier function of RPE cells was also investigated in the former *** Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1.and PKC-εproteins in RPE cells following a prolonged ***,ARPE-1. cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1.and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer ***,silencing RACK1.significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier *** RACK1.plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function.

关键词： Diabetic retinopathy Receptor for activated C kinase 1 Protein kinase C-ε Adult retinal pigment epithelium cell line-1.