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Petroleum Science 2024年第2期21卷 1305-1319页

作者： Nai-liang Li bin Chen School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.

关键词： Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging Correlation

Distributed Deep Reinforcement Learning:A Survey and a Multi-player Multi-agent Learning Toolbox

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Machine Intelligence Research 2024年第3期21卷 411-430页

作者： Qiyue Yin Tongtong Yu Shengqi Shen jun Yang Meijing Zhao Wancheng Ni Kaiqi Huang bin liang liang Wang Institute of Automation Chinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Department of Automation Tsinghua UniversityBeijing 100084China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesBeijing 100190China

With the breakthrough of AlphaGo,deep reinforcement learning has become a recognized technique for solving sequential decision-making *** its reputation,data inefficiency caused by its trial and error learning mechanism makes deep reinforcement learning difficult to apply in a wide range of *** methods have been developed for sample efficient deep reinforcement learning,such as environment modelling,experience transfer,and distributed modifications,among which distributed deep reinforcement learning has shown its potential in various applications,such as human-computer gaming and intelligent *** this paper,we conclude the state of this exciting field,by comparing the classical distributed deep reinforcement learning methods and studying important components to achieve efficient distributed learning,covering single player single agent distributed deep reinforcement learning to the most complex multiple players multiple agents distributed deep reinforcement ***,we review recently released toolboxes that help to realize distributed deep reinforcement learning without many modifications of their non-distributed *** analysing their strengths and weaknesses,a multi-player multi-agent distributed deep reinforcement learning toolbox is developed and released,which is further validated on Wargame,a complex environment,showing the usability of the proposed toolbox for multiple players and multiple agents distributed deep reinforcement learning under complex ***,we try to point out challenges and future trends,hoping that this brief review can provide a guide or a spark for researchers who are interested in distributed deep reinforcement learning.

关键词： Deep reinforcement learning distributed machine learning self-play population-play toolbox

Thermoelectric transport properties of p-type Bi_(2)Se_(3)-Sb_(2)Se_(3)-In_(2)Se_(3) high entropy compounds

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Rare Metals 2024年第7期43卷 3415-3421页

作者： Feng Jiang Cheng-liang Xia Yong-bin Zhu jun Li Yue Chen Wei-Shu Liu Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Mechanical Engineering The University of Hong KongHong Kong 999077China Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

The introduction of entropy concept into thermoelectric materials recently has attracted broad ***,we showed the phase diagram of the ternary systems of Bi_(2)Se_(3)-Sb_(2)Se_(3)-In_(2)Se_(3).Among the high entropy compounds (HECs),we have identified an intrinsic p-type region near our previously reported Bi_(0.8)Sb_(0.8)In_(0.4)Se_(3) in the phase diagram.

关键词： entropy (3) compounds

An improved installation of 2-hydroxy-4-methoxybenzyl(iHmb)method for chemical protein synthesis

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Chinese Chemical Letters 2024年第5期35卷 145-150页

作者： Ying Li Long-Jie Wang Yong-Kang Zhou jun liang bin Xiao Ji-Shen Zheng The First Affiliated Hospital of USTC MOE Key Laboratory for Membraneless Organelles and Cellular DynamicsDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Chemistry University of Science and Technology of ChinaHefei 230027China

The 2-hydroxy-4-methoxybenzyl(Hmb)backbone modification can prevent amide bond-mediated sidereactions(e.g.,aspartimide formation,peptide aggregation)by installing the removable Hmb group into a peptide bond,thus improving the synthesis of long and challenging peptides and ***,its use is largely precluded by the limited Hmb’s installation *** this report,an improved installation of Hmb(iHmb)method was developed to achieve the flexible installation and the convenient removal of *** iHmb method involves two critical steps:(1)oxidative diazotization of the readily installed 2-hydroxy-4-methoxy-5-amino-benzyl(Hmab)to give 2-hydroxy-4-methoxy-5-diazonium-benzyl(Hmdab)by combining soamyl nitrite(IAN)/HBF_(4),and(2)reductive elimination of Hmdab to give the desired Hmb by 1,2-ethanedithiol(EDT).The iHmb method enables the installation of Hmb at any primary amino acid including the highly sterically hindered amino acids(e.g.,valine and isoleucine).The practicality and utility of the iHmb method was demonstrated by one-shot solid-phase synthesis of a challenging aspartimide-prone peptide,the mirror-image version of a hydrophobic peptide and a long-chain peptide up to ***,the iHmb method can be utilized to facilitate chemical protein ligation,as exemplified by the synthesis of the single-spanning membrane protein *** iHmb method expands the toolkit for peptide synthesis and ligation and facilitates the preparation of peptides/proteins.

关键词： Chemical protein synthesis Solid-phase peptide synthesis Removable backbone modification 2-Hydroxy-4-methoxybenzyl(Hmb)group Aspartimide-prone peptides Difficult peptides Membrane proteins

The higher-order topological pumping explored in the 2D acoustic crystal

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 127-133页

作者： Yanqiu Wang bin liang Jianchun Cheng Key Laboratory of Modern Acoustics Ministry of EducationInstitute of AcousticsDepartment of PhysicsNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

The topological pumping has been instrumental in advancing our understanding of topological phase transitions in various physical systems,which can be extended to uncover intriguing higher-order topological phases in the lower-dimensional ***,we propose a theoretical exploration of topological dipole pumping on an acoustic square superlattice by cyclically modulating intracell couplings,which shares the topological nature of an extended three-dimensional system with chiral hinge *** the multipole chiral numbers,we characterize the higher-order topological phases that arise during the *** evolution of topological phase transitions is verified by numerical simulations and shows corner states are transferred across the *** findings can inspire the construction of chiral hinge states in artificial crystals,opening up new possibilities for the design of devices allowing the unidirectional propagation of sound.

关键词： topological phases of matter Thouless pumping acoustic metamaterial

Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-bin liang Bo Li Shao-Ming Fei School of Mathematics and Computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

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Optimal Model Average Prediction in Orthogonal Kriging Models

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Journal of Systems Science & Complexity 2024年第3期37卷 1080-1099页

作者： WANG jun HE Jiabei liang Hua LI Xinmin School of Mathematics and Statistics Qingdao UniversityQingdao 266071China Department of Statistics George Washington UniversityWashington DC 20052USA

The main objective of this paper is to consider model averaging methods for kriging *** paper proposes a Mallows model averaging procedure for the orthogonal kriging model and demonstrate the asymptotic optimality of the model averaging estimators in terms of mean square *** studies are conducted to evaluate the performance of the proposed method and compare it with the competitors to demonstrate its *** authors also analyse a real dataset for an illustration.

关键词： Asymptotic optimality Mallows criterion optimal model averaging orthogonal kriging model

Observational appearances of hairy black holes in the framework of gravitational decoupling

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Communications in Theoretical Physics 2024年第8期76卷 103-117页

作者： Yizhi liang Xin Lyu jun Tao Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu 610065China

We investigate the observational appearance of static and spherically symmetric hairy black holes in the framework of gravitational decoupling with the weak energy condition(WEC). Two types of thin illumination conditions are studied: spherical accretion and disk accretion. As the hairy parameter increases, the size of the photon sphere and photon rings in both models decreases, and the overall luminosity attenuation becomes more pronounced. In spherical accretion, the luminosity of infalling accretion is significantly lower than that of stationary accretion. In disk accretion the luminosity of the black hole is contributed by direct emission, the lensing ring and the photon ring. Employing four types of astrophysical disk luminosity model,we investigate the appearance of halos and note that their luminosities do not superimpose when the source is on or beyond the innermost stable circular orbit.

关键词： hairy black hole shadow gravitational decoupling accretion disk

Retraction note to:RNA-binding protein CPSF6 regulates IBSP to affect pyroptosis in gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2865-2866页

作者： Xue-jun Wang Yong Liu bin Ke Li Zhang Han liang Department of Gastric Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin Clinical Research Center for CancerTianjin Key Laboratory of Digestive CancerTianjin 300060China

The authors have decided to retract the article published on World J Gastrointest Oncol(2023)for further consideration due to data errors and some misunderstandings in communication.

关键词： Retraction note

Systematic study of the synthesis of heavy and superheavy nuclei in 48Ca-induced fusion-evaporation reactions

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Nuclear Science and Techniques 2024年第7期35卷 157-172页

作者： Shi-Hao Zhu Tian-liang Zhao Xiao-jun Bao Department of Physics Collaborative Innovation Center for Quantum EffectsKey Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha410081China School of Nuclear Science and Technology Lanzhou UniversityLanzhou730000China School of Physics Xi’an Jiaotong UniversityXi’an710049China

We systematically studied the evaporation residue cross sections of ^(48)Ca-induced reactions on lanthanide and actinide target nuclei under the Dinuclear System(DNS)model framework to check the reliability and applicability of the *** produce new proton-rich Fl and Lv isotopes through hot fusion reactions in the superheavy element region with Z≥104,we utilized the reactions ^(48)Ca+^(236,238,239) Pu and ^(48)Ca+^(242,243,244,250) ***,owing to the detection limit of available equipment(0.1 pb),only 283Fl and 287−289Lv,which have the maximum evaporation residue cross section values of 0.149,0.130,9.522,and 0.309 pb,respectively,can be ***,to produce neutron-deficient isotopes of actinides near the proton drip line with Z=93−100,we attempted to generate the new isotopes(224−227Pu,228−232,237Cm)using the reactions ^(48)Ca+180,182,183 W and ^(48)Ca+^(184,186,187,192) *** maximum evaporation residue cross section values are 0.07,0.06,0.26,and 0.30 nb for the former set of reactions,and 1.96 pb,5.73 pb,12.16 pb,19.39 pb,54.79 pb,and 6.45 nb for the latter,*** results are expected to provide new information for the future synthesis of unknown neutron-deficient isotopes.

关键词： Dinuclear system(DNS)model Evaporation residue cross section Neutron-deficient isotopes