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Copper-Catalyzed 1,2,5-Trifunctionalization of Terminal Alkynes Using SR as a Transient Directing Group for Radical Translocation

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Chinese Journal of Chemistry 2022年第14期40卷 1667-1673,I0002页

作者： Jian Feng fang Zhang Chenyun shu Gangguo Zhu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of ChemistryZhejiang Normal University688 Yingbin RoadJinhuaZhejiang 321004China

The first Cu-catalyzed 1,2,5-trifunctionalization of abundant terminal alkynes is realized by merging hydrogen atom transfer and traceless directing strategy with SR as a transient group,delivering highly functionalized aldehydes in moderate to excellent yields with broad substrate scope.The synthetic utility of this method was demonstrated by the gram-scale reaction and downstream transformations of the resultant products.Given the high efficient installation of three different functional groups in a single reaction,it can serve as a very attractive method for rapidly assembling complex molecules from readily available starting materials.

关键词： Radical reaction Alkyne Trifunctionalization Hydrogen atom transfer Copper

Effects of constant light and dark conditions on the locomotor activity,body mass,and body temperature rhythms of Eurasian Tree Sparrows(Passer montanus)

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Avian Research 2023年第3期14卷 435-442页

作者： Lirong Zuo Ibrahim MAhmad Yuanyuan Liu Limin Wang Shu Fang Dongming Li Hebei Key Laboratory of Animal Physiology Biochemistry and Molecular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang050024Hebei ProvinceChina Hebei Collaborative Innovation Center for Eco-Environment Hebei Normal UniversityShijiazhuang050024China

Light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior and physiology,the mechanisms by which they adapt and adjust to abnormal photoperiod conditions,such as artificial light,have yet to be fully elucidated.Here,the circadian rhythms of the body mass,activity,and core and peripheral body temperatures of the Eurasian Tree Sparrow(Passer montanus,ETS)-a diurnal passerine-were examined under three different lighting conditions:constant light(LL),constant darkness(DD),and normal light-dark cycles(LD).Our results showed that the activity,body mass,core,tarsometatarsus,and eye temperatures of the ETSs varied significantly with treatment,time,and the interaction between treatment and time;however,there was no significant change in body mass in response to the interaction between time and treatment.Under LD conditions,the ETSs exhibited significant circadian rhythms in activity and core,tarsometatarsus,and eye temperatures.Under LL conditions,only the core temperature exhibited significant rhythmicity.Under DD conditions,there were no significant circadian rhythms in activity,body mass,and eye temperature;however,the core and tarsometatarsus temperatures remained rhythmic.Our results indicate that the core body temperature rhythm of ETS is endogenous and can be maintained under abnormal photoperiods.In contrast,the activity and body surface temperature,uncoupled from the core body temperature under abnormal photoperiod conditions,strongly depend on light.These results differ from those of other diurnal avian species,suggesting a unique coping mechanism of ETS in response to an abnormal photoperiod.

关键词： Eurasian Tree Sparrow Activity Body mass Body temperature Circadian rhythm

Glucagonoma syndrome with necrolytic migratory erythema as initial manifestation

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Hepatobiliary & Pancreatic Diseases International 2021年第6期20卷 598-600页

作者： Wei-fang Zhu shu-Sen Zheng Department of Dermatology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Hepatobiliary and Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

To the Editor:Necrolytic migratory erythema(NME)is a group of cutaneous lesions characterized by periodic episodes of annular or figurative dark red plaques,which are typically accompanied by blisters,erosions,and crusting.It is often associated with glucagonoma.Glucagonoma is an extremely rare neuroendocrine tumor that arises from pancreatic isletαcells and manifests as elevated glucagon,with an incidence of about 1 in 20 million per year[1,2].

关键词： erythema elevated islet

Multi-Resources Management in 6G-Oriented Terrestrial-Satellite Network

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China Communications 2021年第9期18卷 24-36页

作者： shu Fu Bibo Wu Shaohua Wu fang fang College of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Space Information Network and Intelligent Information Fusion Chongqing UniversityChongqing 400044China Communication Engineering Research Centre Harbin Institute of Technology(Shenzhen)Guangdong 518055China Peng Cheng Laboratory Shenzhen 518055China Department of Engineering Durham UniversityDurham DH13LEU.K

The six-generation(6G)wireless network is expected to satisfy the requirements of ubiquitous connectivity and intelligent endogenous.Terrestrialsatellite networks(TSN)enable seamless coverage for terrestrial users in a wide area,making it very promising in 6G.As data traffic in TSNs surges,the integrated management for caching,computing,and communication(3C)has attracted much research attention.In this paper,we investigate the multi-resource management in the uplink and downlink transmission of TSN,respectively.In particularly,we aim to guarantee both throughput fairness and data security in the uplink transmission of TSN.Considering the intermittent communication of the satellite,we introduce two kinds of relays,i.e.,terrestrial relays(TRs)and aerial relays(ARs)to improve the system throughput performance in the downlink transmission of TSN.Finally,we study a specific case of TSN with the uplink and downlink transmission,and the corresponding simulation results validate the effectiveness of our proposed schemes.

关键词： downlink transmission multi-resource management relay terrestrial-satellite networks up-link transmission

Precise Evolutionary Asteroseismology of High-AmplitudeδScuti Star AE Ursae Majoris

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Research in Astronomy and Astrophysics 2022年第10期22卷 61-76页

作者： Hui-fang Xue Jia-shu Niu Jian-Ning Fu Department of Physics Taiyuan Normal UniversityJinzhong 030619China Institute of Computational and Applied Physics Taiyuan Normal UniversityJinzhong 030619China Institute of Theoretical Physics Shanxi UniversityTaiyuan 030006China State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China Department of Astronomy Beijing Normal UniversityBeijing 100875China

Stellar structure and evolution theory is one of the bases in modern astronomy.Stellar inner structures and their evolutionary states can be precisely tested by asteroseismology,since the inner information is brought to the stellar surface by the global oscillating waves and becomes observable.For stellar evolutionary speed(i.e.,how long timescale does a star stay at a special evolution phase?),because of the insurmountable gap between the timescales of the evolutionary history of human civilization and a star,it can only be roughly tested by ensemble of stars in different evolutionary stages in most cases,and all the snapshots of these stars make up our global view of stellar evolution.The effect of stellar evolution on the structure and the corresponding global size of a pulsating star will lead to tiny period variations of its pulsation modes,which are the most valuable indicators of its evolutionary state and can be used to test the stellar evolution theory by a single star rather than ensemble of stars.Here,we report a High-AmplitudeδScuti star AE Ursae Majoris,which is located in the post main-sequence(MS)evolutionary stage and its observed linear period variation rate can be practically ascribed to its evolutionary effect.The result tests the stellar evolution theory from the pre-MS to post-MS with an unprecedented precision by a single star,and the framework can be extended to other type of pulsating stars to perform precise evolutionary asteroseismology,which aims to test the current stellar evolution theory in different evolutionary stages,discover the discrepancies between the theory and observations,and ultimately build a complete and precise stellar evolution theory to backtrack the history of each of these stars.

关键词： stars variables delta Scuti-stars evolution-stars oscillations(including pulsations)

Design and Implementation of Nonlinear Precoding for MIMO-SDMA Toward 6G Wireless

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China Communications 2024年第1期21卷 69-87页

作者： Chaowu Wu Yue Xiao Shu Fang Gang Wu National Key Laboratory of Wireless Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we present a novel and robust nonlinear precoding(NLP)design and detection structure specifically tailored for multiple-input multipleoutput space division multiple access(MIMO-SDMA)systems toward 6G wireless.Our approach aims to effectively mitigate the impact of imperfect channel estimation by leveraging the channel fluctuation mean square error(MSE)for reconstructing a highly accurate precoding matrix at the transmitter.Furthermore,we introduce a simplified receiver structure that eliminates the need for equalization,resulting in reduced interference and notable enhancements in overall system performance.We conduct both computer simulations and experimental tests to validate the efficacy of our proposed approach.The results reveals that the proposed NLP scheme offers significant performance improvements,making it particularly well-suited for the forthcoming 6G wireless.

关键词： MIMO-SDMA nonlinear precoding Tomlinson-Harashima precoding(THP) vector perturbation(VP)

On Free Boundary Problem for the Non-Newtonian Shear Thickening Fluids

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Journal of Partial Differential Equations 2021年第1期34卷 14-41页

作者： WANG shu YUAN fang College of Applied Sciences Beijing University of TechnologyBeijing 100124China China Everbright Bank Beijing 100054China

The aim of this paper is to explore the free boundary problem for the NonNewtonian shear thickening fluids.These fluids not only have vacuum,but also have strong nonlinear properties.In this paper,a class of approximate solutions is first constructed,and some uniform estimates are obtained for these approximate solutions.Finally,the existence of free boundary problem solutions is proved by these uniform estimates.

关键词： On free boundary problem the non-Newtonian shear thickening fluids vacuum

Outlier Detection for Water Supply Data Based on Joint Auto-Encoder

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Computers, Materials & Continua 2020年第7期64卷 541-555页

作者： Shu Fang Lei Huang Yi Wan Weize Sun Jingxin Xu Guangdong Laboratory of Artificial-Intelligence and Cyber-Economics(SZ) College of Electronics and Information EngineeringShenzhen UniversityShenzhen518061China Water Resources Management Center of Ministry of Water Resources BeijingChina Departmet of Housing and Public Works QueenslandAustralia

With the development of science and technology,the status of the water environment has received more and more attention.In this paper,we propose a deep learning model,named a Joint Auto-Encoder network,to solve the problem of outlier detection in water supply data.The Joint Auto-Encoder network first expands the size of training data and extracts the useful features from the input data,and then reconstructs the input data effectively into an output.The outliers are detected based on the network’s reconstruction errors,with a larger reconstruction error indicating a higher rate to be an outlier.For water supply data,there are mainly two types of outliers:outliers with large values and those with values closed to zero.We set two separate thresholds,and,for the reconstruction errors to detect the two types of outliers respectively.The data samples with reconstruction errors exceeding the thresholds are voted to be outliers.The two thresholds can be calculated by the classification confusion matrix and the receiver operating characteristic(ROC)curve.We have also performed comparisons between the Joint Auto-Encoder and the vanilla Auto-Encoder in this paper on both the synthesis data set and the MNIST data set.As a result,our model has proved to outperform the vanilla Auto-Encoder and some other outlier detection approaches with the recall rate of 98.94 percent in water supply data.

关键词： Water supply data outlier detection auto-encoder deep learning

A Polynomial-Time Algorithm with Tight Error Bounds for Single-Period Unit Commitment Problem

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Journal of the Operations Research Society of China 2023年第1期11卷 1-28页

作者： Ruo-Tian Gao shu-Cherng fang Cheng Lu Wen-Xun Xing Big Data Center of State Grid Corporation of China Beijing 100053China Department of Industrial and System Engineering North Carolina State UniversityRaleigh 27695-7906USA School of Economics and Management North China Electric Power UniversityBeijing 102206China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

This paper proposes a Lagrangian dual-based polynomial-time approximation algorithm for solving the single-period unit commitment problem,which can be formulated as a mixed-integer quadratic programming problem and proven to be NP-hard.Tight theoretical bounds for the absolute errors and relative errors of the approximate solutions generated by the proposed algorithm are provided.Computational results support the effectiveness and efficiency of the proposed algorithm for solving large-scale problems.

关键词： Nonlinear programming Lagrangian dual Unit commitment problem Mixed-integer quadratic programming Convex relaxation