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Nutrient transport following water transfer through the world's largest water diversion channel

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Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui Cheng Hong Zhang wei yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin ***,the distribution and transport of nutrients along the channel were poorly *** on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this *** results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main *** temperature difference was the major factor in the large fluctuations of water quality indicators over *** nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving *** deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,*** 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main *** increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main *** study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities

Uncarialines A-E,new alkaloids from Uncaria rhynchophylla and their anticoagulant activity

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Natural Products and Bioprospecting 2023年第1期13卷 598-606页

作者： Ke-Pu Huang Li-Li Xu Sheng Li yin-ling wei Lian Yang Xiao-Jiang Hao Hong-Ping He Yu Zhang School of Chinese Materia Medica Yunnan University of Chinese MedicineKunming 650500People’s Republic of China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China

Uncarialines A-E(1-5),five undescribed monoterpene indole alkaloids,together with five known analogues were obtained from the stems of Uncaria *** 1-3 were unique 3,4-seco-tricyclic alkaloids with a 6/5/10 ring system,while 4 and 5 possessed a rare rearranged scaffold originated from corynantheine-type alkaloids with C-2/C-7 *** structures were characterized by a comprehensive analysis of MS,NMR,and *** effects on blood clotting times of human plasma were evaluated and alkaloid 5 had a slight prolongation effect on both thrombin time and activated partial thromboplastin time(p<0.001).

关键词： Uncaria rhynchophylla Monoterpene indole alkaloids Uncarialines A-E Anticoagulant activity

Nitric oxide assists nitrogen reduction reaction on 2D MBene: A theoretical study

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Chinese Chemical Letters 2024年第5期35卷 428-433页

作者： Chaozheng He Jia Wang ling Fu wei wei Henan Engineering Center of New Energy Battery Materials College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu 476000China School of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory/Collaborative Innovation Center of Chemical Energy Storage&Novel Cell TechnologyLiaocheng UniversityLiaocheng 252059China Institute of Environment and Energy Catalysis Shaanxi Key Laboratory of Optoelectronic Functional Materials and DevicesSchool of Materials Science and Chemical EngineeringXi’an Technological UniversityXi’an 710021China College of Resources and Environmental Engineering Tianshui Normal UniversityTianshui 741001China

Electrocatalytic synthesis of ammonia as an environment-friendly and sustainable development method has received widespread attention in recent ***-dimensional(2D)materials are a promising catalyst for ammonia synthesis due to their large surface *** this work,we have constructed a series of 2D metal borides(MBenes)with transition metal(TM)defects(TMd-MBenes)and comprehensively calculated the reactivity of electrocatalytic synthesis of ammonia-based on density functional *** results have demonstrated that the TMd-MBenes can effectively activate nitrogen oxide(NO)and nitrogen(N2)molecules *** interesting,the co-chemisorption of O atoms,dissociated from NO,can facilitate the spilled of the inert N2 molecules into single N atoms,which can further hydrogenate into ammonia easily with an ultralow limiting potential of 0.59 V on *** research has not only provided clues for catalyst design for experimental study but also paved the way for the industrial application of electrocatalytic ammonia synthesis.

关键词： 2D mbenes Nitrogen electro-reduction DFT N_(2)activation Ammonia synthesis

Analytic optimal pose tracking control in close-range proximity operations with a non-cooperative target

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Chinese Journal of Aeronautics 2024年第5期37卷 410-425页

作者： Caisheng wei Guanhua HUANG Zeyang yin Qifeng CHEN School of Automation Central South UniversityChangsha 410083China

This paper investigates an analytical optimal pose tracking control problem for chaser spacecraft during the close-range proximity operations with a non-cooperative space target subject to attitude tumbling and unknown orbital ***,the relative translational motion between the orbital target and the chaser spacecraft is described in the Line-of-Sight(LOS)coordinate frame along with attitude quaternion ***,based on the coupled 6-Degree of Freedom(DOF)pose dynamic model,an analytical optimal control action consisting of constrained optimal control value,application time and its duration are proposed via exploring the iterative sequential action control ***,the global closed-loop asymptotic stability of the proposed predictive control action is presented and *** with traditional proximity control schemes,the highlighting advantages are that the application time and duration of the devised controller is applied discretely in light of the influence of the instantaneous pose configuration on the pose tracking performance with less energy consumptions rather than at each sample ***,three groups of illustrative examples are organized to validate the effectiveness of the proposed analytical optimal pose tracking control scheme.

关键词： Optimal control Close-range proximity operation Non-cooperative space target Coupled attitude and orbit control Iterative sequential action control

Multi-instance partial-label learning: towards exploiting dual inexact supervision

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Science China(Information Sciences) 2024年第3期67卷 48-61页

作者： wei TANG weijia ZHANG Min-ling ZHANG School of Computer Science and Engineering Southeast University Key Laboratory of Computer Network and Information Integration (Southeast University) Ministry of Education School of Information and Physical Sciences The University of Newcastle

Weakly supervised machine learning algorithms are able to learn from ambiguous samples or labels, e.g., multi-instance learning or partial-label learning. However, in some real-world tasks, each training sample is associated with not only multiple instances but also a candidate label set that contains one groundtruth label and some false positive labels. Specifically, at least one instance pertains to the ground-truth label while no instance belongs to the false positive labels. In this paper, we formalize such problems as multi-instance partial-label learning(MIPL). Existing multi-instance learning algorithms and partial-label learning algorithms are suboptimal for solving MIPL problems since the former fails to disambiguate a candidate label set, and the latter cannot handle a multi-instance bag. To address these issues, a tailored algorithm named MIPLGP, i.e., multi-instance partial-label learning with Gaussian processes, is *** first assigns each instance with a candidate label set in an augmented label space, then transforms the candidate label set into a logarithmic space to yield the disambiguated and continuous labels via an exclusive disambiguation strategy, and last induces a model based on the Gaussian processes. Experimental results on various datasets validate that MIPLGP is superior to well-established multi-instance learning and partial-label learning algorithms for solving MIPL problems.

关键词： machine learning multi-instance partial-label learning multi-instance learning partial-label learning Gaussian processes

Polyelectrolytes of Inorganic Polyoxometalates:Prospecting New Charged Polymers for Advanced Applications

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Chinese Journal of Polymer Science 2024年第9期42卷 1254-1269,I0005页

作者： De-yin Wang Zhuo-Qun Lu wei Wang College of Medical Linyi UniversityLinyi276000China Center for Synthetic Soft Materials Key Laboratory of Functional Polymer Materials of the Ministry of EducationInstitute of Polymer ChemistryNankai UniversityTianjin300071China

Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic(e.g.,pyridinium,ammonium)or anionic(e.g.,sulfonate,carboxylate)groups,which possess special functions from the features of counterions,such as dissociation to charged species,mechanical stability,phase behavior,***,functional polyelectrolytes have been widely applied in many *** this perspective,we present some progresses in the studies of poly(polyoxometalate)s,denoted as poly(POM)s,as a kind of new charged polymers/polyelectrolytes,by covalent bonding between the inorganic polyoxometalate(POM)clusters and the organic polymer *** to the distinct positions of POMs in polymer chain and functions of poly(POM)s,they are divided into the following four categories:crosslinked poly(POM);side-chain poly(POM);backbone poly(POM),including poly(POM)-conjugated polymer hybrid and block poly(POM)-polymer;and POM-based covalent organic framework(PCOF).This perspective introduces the synthesis methods of poly(POM)polyelectrolytes and their macromolecular and aggregate structural characteristics,while also focusing on their properties and *** application areas include catalysis,thermal resistance,optical functions,fuel cells and batteries,etc.

关键词： Charged polymer Polyelectrolyte Polyoxometalate Poly(polyoxometalate) Covalent organic framework

Track Defects Recognition Based on Axle-Box Vibration Acceleration and Deep- Learning Techniques

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Structural Durability & Health Monitoring 2024年第5期18卷 623-640页

作者： Xianxian yin Shimin yin Yiming Bu Xiukun wei School of Transportation Engineering Shandong Jianzhu UniversityJinan250101China China Construction Eighth Bureau(Shandong)Design Consulting Co. Ltd.Jinan250100China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing100044China

As an important component of load transfer,various fatigue damages occur in the track as the rail service life and train trafﬁc increase gradually,such as rail corrugation,rail joint damage,uneven thermite welds,rail squats fas-tener defects,***-time recognition of track defects plays a vital role in ensuring the safe and stable operation of rail *** this paper,an intelligent and innovative method is proposed to detect the track defects by using axle-box vibration acceleration and deep learning network,and the coexistence of the above-mentioned typical track defects in the track system is ***,the dynamic relationship between the track defects(using the example of the fastening defects)and the axle-box vibration acceleration(ABVA)is investigated using the dynamic vehicle-track ***,a simulation model for the coupled dynamics of the vehicle and track with different track defects is established,and the wavelet power spectrum(WPS)analysis is performed for the vibra-tion acceleration signals of the axle box to extract the characteristic ***,using wavelet spectrum photos as input,an automatic detection technique based on the deep convolution neural network(DCNN)is sug-gested to realize the real-time intelligent detection and identiﬁcation of various track ***ﬁndings demonstrate that the suggested approach achieves a 96.72%classiﬁcation accuracy.

关键词： Track defects intelligent detection deep convolution neural network acceleration of axle-box vibration

Intelligent Reflecting Surface Assisted Transmission Optimization Strategies in Wireless Networks

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China Communications 2024年第4期21卷 120-135页

作者： He Xinxin Qi Xuan Meng wei Liu wei yin Changchuan School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Wireless Power Transfer(WPT)technology can provide real-time power for many terminal devices in Internet of Things(IoT)through millimeterWave(mmWave)to support applications with large capacity and low *** the intelligent reflecting surface(IRS)can be adopted to create effective virtual links to address the mmWave blockage problem,the conventional solutions only adopt IRS in the downlink from the Base Station(BS)to the users to enhance the received signal *** practice,the reflection of IRS is also applicable to the uplink to improve the spectral *** is a challenging to jointly optimize IRS beamforming and system resource allocation for wireless energy acquisition and information *** this paper,we first design a Low-Energy Adaptive Clustering Hierarchy(LEACH)clustering protocol for clustering and data ***,the problem of maximizing the minimum system spectral efficiency is constructed by jointly optimizing the transmit power of sensor devices,the uplink and downlink transmission times,the active beamforming at the BS,and the IRS dynamic *** solve this non-convex optimization problem,we propose an alternating optimization(AO)-based joint solution *** results show that the use of IRS dynamic beamforming can significantly improve the spectral efficiency of the system,and ensure the reliability of equipment communication and the sustainability of energy supply under NLOS link.

关键词： intelligent reflecting surface(IRS) joint optimization millimeter wave wireless information transmission(WIT) wireless power transfer(WPT)

Visible-light-induced controllable transformations of cumulative aryldienes through an energy transfer process

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Science China Chemistry 2024年

作者： ling Qian Ziqi Yu Jiaxin Liu yin wei Min Shi Key Laboratory for Advanced Materials and Institute of Fine Chemicals Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center School of Chemistry & Molecular Engineering East China University of Science and Technology Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular Synthesis University of Chinese Academy of SciencesShanghai Institute of Organic Chemistry Chinese Academy of Sciences

In this work, we report a visible light-induced energy transfer process related photochemical protocol of cumulative diene containing compounds for the construction of benzocyclohexene skeletons or the corresponding aromatized structures through an energy transfer process, 1,5-hydrogen atom transfer and a 6π electrocyclization or demethoxylation in the presence of different photocatalysts such as [Ir(dF（Me）ppy)2（dtbbpy）]PF6or thioxanthone. This newly developed photochemical strategy is characterized by mild conditions, broad substrate applicability, good functional group tolerance and good yields. The mechanistic paradigm was clarified by deuterium labeling, kinetic, photophysical and electrochemical analyses, control experiments and density functional theory（DFT） calculations. The transformation of the obtained product to the drug-like molecules such as Sertraline and the luminescent conjugated aromatic compounds has also been disclosed.

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