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Rapid discovery of two unprecedented meroterpenoids from Daphne altaica *** molecular networking integrated with MolNetEnhancer and Network Annotation Propagation

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Chinese Chemical Letters 2024年第8期35卷 294-298页

作者： Wei-Yu Zhou Zi-Han Xi Ning-Ning Du Li Ye ming-hao jiang Jin-Le hao Bin Lin Guo-Dong Yao Xiao-Xiao Huang Shao-jiang Song Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research&Development Liaoning ProvinceEngineering Research Center of Natural Medicine Active Molecule Research&DevelopmentLiaoning ProvinceKey Laboratory of Natural Bioactive Compounds Discovery&ModificationShenyangSchool of Traditional Chinese Materia Medic1Shenyang Pharmaceutical UniversityShenyang 110016China Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyang 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China

Under the guidance of the approach which integrates molecular networking,MolNetEnhancer and Net-work Annotation Propagation(NAP),daphnaltaicanoids A and B(1 and 2)with unprecedented 9-oxa-tetracyclo[6.***.1.0^(2,6).0^(8,13)]pentadecane and tetracyclo[5.***.0.1^(2,5).2^(4,11)]tridecane central frameworks were iso-lated from Daphne altaica Pall.,representing two types of unparalleled meroterpenoid *** struc-tures were elucidated by extensive spectroscopic analysis,nuclear magnetic resonance(NMR)calcula-tions,DP4+analysis and electronic circular dichroism(ECD)*** plausible biosynthetic path-ways for 1 and 2 were ***,2 exerted potent neuroprotective activities which were su-perior to trolox at 12.5 and 25μmol/***,1 and 2 exhibited more noticeable acetylcholinesterase inhibitory activities than *** docking simulations were performed to explore the inter-molecular interaction of compounds 1 and 2 with *** bioactivity evaluation results highlight the prospects of 1 and 2 as a novel category of neurological agents.

关键词： Daphne altaica Pall. Molecular networking MolNetEnhancer NAP Unprecedented meroterpenoid frameworks Neuroprotective activities Acetylcholinesterase inhibitors

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Ambient electrocatalytic synthesis of urea by co-reduction of NO_(3)^(-) and CO_(2) over graphene-supported In_(2)O_(3)

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Chinese Chemical Letters 2024年第3期35卷 538-543页

作者： Yini Mao Yong jiang hao Liu Yimin jiang ming Li Wei Su Rongxing He Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University) Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Key Laboratory of Beibu Gulf Environment Change and Resources Utilization(Nanning Normal University) Ministry of EducationCollege of Chemistry and Life ScienceNanning Normal UniversityNanning 530000China

Urea plays a vital role in the sustainable development of mankind as it is one of the most important nitrogen *** synthesis of urea is accompanied by a high level of energy consumption while electrocatalytic methods suffer from low yields and poor *** work achieves efficient synthesis of urea by designing the graphene-In_(2)O_(3)electrocatalysts for the co-activated reduction of nitrate and carbon dioxide,where the formation rate of urea,Faraday efficiency(FE)and carbon selectivity at-0.35 V *** can reach 357.47μg mg^(-1)h^(-1),10.46%and~100%,***,the key intermediates in the C–N coupling reaction are demonstrated to be*NH_(2)and*CO_(2),which is of novelty compared to previous *** work may provide inspiration for subsequent studies on the reaction mechanism of the electrochemical synthesis of urea,as well as theoretical guidance for the sustainable synthesis of some other important chemical substances.

关键词： Graphene-supported In_(2)O_(3) Dispersion effect Efficient C-N coupling Key intermediate Urea

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Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production

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China Ocean Engineering 2024年第2期38卷 338-351页

作者： SUN Huan-zhao CHANG Yuan-jiang SUN Bao-jiang WANG Kang CHEN Guo-ming LI hao DAI Yong-guo Centre for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China jiangsu Shuguang Oil Tools Co. LtdTaizhou 225532China

Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate ***,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production ***,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during *** fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate *** on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is *** analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability *** higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even *** work can provide a theoretical reference for the stability maintaining of the production well.

关键词： natural gas hydrate production well depressurization production formation deformation stability deterioration

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An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

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Investigation on UV-curing Reprocessable Thermosets Bearing Hindered Urea Bonds and Their Composites with Modified Zinc Oxide Nanoparticles

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Chinese Journal of Polymer Science 2024年第6期42卷 751-765页

作者： Jun-hao Zhou Li-ming Tang Key Laboratory of Advanced Materials of Ministry of Education of China Department of Chemical EngineeringTsinghua UniversityBeijing100084China

In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot *** prepolymers were characterized fully by various ***,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and *** from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical ***,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their *** influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then *** composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT *** addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.

关键词： Polyurethane-urea methacrylate Hindered urea bond ZnO nanoparticles Reprocessing UV curing

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Novel Sum-of-Sinusoids Simulation Channel Modeling for 6G Multiple-Input Multiple-Output Vehicle-to-Everything Communications

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China Communications 2024年第1期21卷 242-259页

作者： hao jiang Hongming Zhang Ting Liu College of Artificial Intelligence Nanjing University of Information Science and Technology210044China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsChina

In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)*** the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless *** statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and *** results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and *** proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems.

关键词： complex CIRs LoS and NLoS propagation components MIMO V2X communication environments SoS simulation channel model statistical properties

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Numerical insight into heat transfer enhancement by granules inner-migration in a moving bed:A performance comparison between slanted-stick and plow-shaped agitator

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Particuology 2024年第6期89卷 109-116页

作者： Binfan jiang hao Pei Dehong Xia Haiyang Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Shunde Graduate School of University of Science and Technology Beijing Guangdong 528399China Jianlong Group&USTB Joint Laboratory Beijing 100083China

Waste heat recovery of high-temperature granules is one of the most promising sustainable energy supply and carbon reduction ways for industry.A moving bed indirect heat exchanger(MBIHE)with inner-migration was proposed for granular heat *** migration and the enhanced heat transfer induced by two types of agitators(i.e.,agitator with slanted stick A_(s)and with plow-shaped surface A_(p))in the MBIHE are analyzed based on DEM coupled with *** to the effective agitation,the average heat transfer coefficient in the granule side is enhanced to∼3 times compared to that without *** heat recovery efficiency in the moving bed reached more than 70%with the agitations of either A_(s)or A_(p).The heat efficiency of A_(s)is∼7%higher than that of A_(p),but with at least 60%greater rotational *** ensure reliable agitation,the A_(p)is suggested to be adopted in the MBIHE to induce granule migration.

关键词： Waste heat recovery High-temperature granule Granule migration Heat transfer enhancement Industry energy saving

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Numerical and experimental investigation into the evolution of the shock wave when a muzzle jet impacts a constrained moving body

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Defence Technology（防务技术） 2024年第3期33卷 317-326页

作者： Zijie Li hao Wang Changshun Chen Kun jiang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210016China

The gun-track launch system is a new special launch device that connects the track outside the *** it is constrained by the track,the characteristics of development of the muzzle jet differ from those of the traditional muzzle ***,it changes from freely developing to doing so in a constrained manner,where this results in an asymmetric direction of flow as well as spatio-temporal coupling-induced interference between various shock waves and the formation of *** this background,the authors of this article formulate and consider the development and characteristics of evolution of the muzzle jet as it impacts a constrained moving *** designed simulations to test the gun-track launch system,and established a numerical model based on the dynamic grid method to explore the development and characteristics of propagation of disturbances when the muzzle jet impacted a constrained moving *** also considered models without a constrained track for the sake of *** results showed that the muzzle jet assumed a circumferential asymmetric shape,and tended to develop in the area above the *** the test platform was close to the ground,the muzzle jet was subjected to reflections from it that enhanced the development and evolution of various forms of shock waves and vortices in the muzzle jet to exacerbate its rate of distortion and asymmetric *** in turn led to significant differences in the changes in pressure at symmetric points that would otherwise have been *** results of a comparative analysis showed that the constrained track could hinder the influence of reflections from the ground on the muzzle jet to some extent,and could reduce the velocity of the shock waves inducing the motion of the muzzle as well as the Mach number of the moving *** work here provides a theoretical basis and the requisite technical support for applications of the gun-track launch *** also sheds light on the

关键词： Shock wave/vortex interference Muzzle jet Constrained boundary Dynamic grid

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On the Strong Approximation for a Simple Reentrant Line in Light Traffic Under First-buffer First-served Service Discipline

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 823-839页

作者： Kai-ming YANG Yong-jiang GUO School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-class reentrant line under first-buffer first-served(FBFS)service discipline in light traffic,we firstly construct the strong approximations for performance measures including the queue length,workload,busy time and idle time *** on the obtained strong approximations,we use a strong approximation method to find all the law of the iterated logarithms(LILs)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival and service times,and characterize the fluctuations around their fluid approximations.

关键词： reentrant line queueing network FBFS service discipline strong approximation LIL Brownian motion

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STDNet: A Spatio-Temporal Decomposition Neural Network for Multivariate Time Series Forecasting

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Tsinghua Science and Technology 2024年第4期29卷 1232-1247页

作者： Zhuolun jiang Zefei Ning hao Miao Li Wang College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyJinzhong 030600China

Long-term multivariate time series forecasting is an important task in engineering applications. It helps grasp the future development trend of data in real-time, which is of great significance for a wide variety of fields. Due to the non-linear and unstable characteristics of multivariate time series, the existing methods encounter difficulties in analyzing complex high-dimensional data and capturing latent relationships between multivariates in time series, thus affecting the performance of long-term prediction. In this paper, we propose a novel time series forecasting model based on multilayer perceptron that combines spatio-temporal decomposition and doubly residual stacking, namely Spatio-Temporal Decomposition Neural Network (STDNet). We decompose the originally complex and unstable time series into two parts, temporal term and spatial term. We design temporal module based on auto-correlation mechanism to discover temporal dependencies at the sub-series level, and spatial module based on convolutional neural network and self-attention mechanism to integrate multivariate information from two dimensions, global and local, respectively. Then we integrate the results obtained from the different modules to get the final forecast. Extensive experiments on four real-world datasets show that STDNet significantly outperforms other state-of-the-art methods, which provides an effective solution for long-term time series forecasting.

关键词： time series forecasting multivariate time series spatio-temporal decomposition

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