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Rare Metals 2018年第9期37卷 778-788页

作者： Xue-Mei Yang Hong-Zhen Guo ze-Kun Yao Shi-Chong yuan She-Wei Xin School of Materials Science and Engineering Northwestern Polytechnical University Deyang Wan Hang Die Forging Co. Ltd.China National Erzhong Group Co. Titanium Alloy Research Center Northwest Institute for Nonferrous Metal Research

The high-temperature plastic deformation behavior of BT25y alloy with an initial equiaxed microstructure was investigated by hot compression tests. Processing maps were established to evaluate the power dissipation efficiency （η） and identify the flow instability regions. When the strain reaches steady state, the optimum processing window is distributed in the area covering most of the studied deformation temperatures and strain rates of 1 × 10-2 to 1× 10-1 s-1. True strain has great effects on the power dissipation efficiency under the condition of 880 ℃/1× 10-3 s-1, but the efficiency values remain approximately constant （η= 0.40） at conditions of 900-940 ℃/1× 10-2 to 1 × 10-1 S-1 and 980-1000 ℃/ 1× 10-1 s- 1. Besides, the instability regions are distributed in high strain rate areas no matter how many of the strains. Based on the processing map and microstructural observa- tion, it can be concluded that the deformation mechanisms related to Region I with small strain rate and lower temper- ature in α＋β phase field, Region II with medium strain rate and higher temperature inα＋β phase field, Region III with medium strain rate and high temperature in βphase field are superplasticity and strain-induced transformation, dynamicrecrystallization （DRX） and phase transformation, β phase dynamic recovery and local DRX, respectively.

关键词： BT25y alloy Hot deformation Processingmap Microstructural evolution

Discrimination of pp solar neutrinos and^(14)C double pile-up events in a large-scale LS detector

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Nuclear Science and Techniques 2023年第9期34卷 69-81页

作者： Guo-Ming Chen Xin Zhang ze-yuan Yu Si-yuan Zhang Yu Xu Wen-Jie Wu Yao-Guang Wang Yong-Bo Huang School of Physical Science and Technology Guangxi UniversityNanning 530004China Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Department of Physics and Astronomy University of CaliforniaIrvineCAUSA

As a unique probe,the precision measurement of pp solar neutrinos is important for studying the sun’s energy mechanism as it enables monitoring the thermodynamic equilibrium and studying neutrino oscillations in the vacuum-dominated *** a large-scale liquid scintillator detector,a bottleneck for pp solar neutrino detection is the pile-up events of intrinsic14C *** paper presents a few approaches to discriminating between pp solar neutrinos and ^(14)C pile-up events by considering the differences in their time and spatial *** this study,a Geant4-based Monte Carlo simulation is *** analysis and deep learning technology are adopted to investigate the capability of ^(14)C pile-up *** BDTG (boosted decision trees with gradient boosting) model and VGG network demonstrate good performance in discriminating pp solar neutrinos and ^(14)C double pile-up *** the ^(14)C concentration assumption of 5×10-18g/g,the signal significance can achieve 10.3 and 15.6 using the statistics of only one *** this case,the signal efficiency for discrimination using the BDTG model while rejecting 99.18% ^(14)C double pile-up events is 51.1%,and that for the case where the VGG network is used while rejecting 99.81%of the ^(14)C double pile-up events is 42.7%.

关键词： Liquid scintillator detector pp solar neutrinos 14C pile-up Multivariate analysis Deep learning

Bilinear Forms and Dark-Dark Solitons for the Coupled Cubic-Quintic Nonlinear Schrodinger Equations with Variable Coefficients in a Twin-Core Optical Fiber or Non-Kerr Medium

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Communications in Theoretical Physics 2019年第12期71卷 1393-1398页

作者： Mei-Xia Chu Bo Tian Yu-Qiang yuan ze Zhang He-yuan Tian State Key Laboratory of Information Photonics and Optical Communications and School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

Twin-core optical fibers are applied in such fields as the optical sensing and optical communication,and propagation of the pulses,Gauss beams and laser beams in the non-Kerr media is *** in this paper are the coupled cubic-quintic nonlinear Schrodinger equations with variable coefficients,which describe the effects of quintic nonlinearity for the ultrashort optical pulse propagation in a twin-core optical fiber or non-Kerr *** on the integrable conditions,bilinear forms are derived,and dark-dark soliton solutions can be constructed in terms of the Gramian via the Kadomtsev-Petviashvili hierarchy *** and interaction of the dark-dark solitons are presented and discussed through the graphic *** different values of the delayed nonlinear response effect b(z),where z represents direction of the propagation,the linear-and parabolic-shaped one dark-dark soltions can be *** between the parabolic-and periodic-shaped two dark-dark solitons are presented with b(z)as the linear and periodic functions,*** of velocities of the two dark-dark solitons vary with z and the amplitudes of the solitons remain unchanged can be *** between the two dark-dark solitons of different types are displayed,and we observe that the velocity of one soliton is zero and direction of the velocity of the other soliton vary with *** find that those interactions are elastic.

关键词： optical fiber coupled cubic-quintic nonlinear Schrodinger equations dark-dark solitons Kadomtsev-Petviashvili hierarchy reduction

Austenite Grain Growth in Heat Affected Zone of Zr-Ti Bearing Microalloyed Steel

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Journal of Iron and Steel Research International 2012年第2期19卷 73-78页

作者： ZHENG Lei yuan ze-xi SONG Shen-hua XI Tian-hui WANG Qian Department of Materials Science and Engineering Shenzhen Graduate School Harbin Institute of TechnologyShenzhen 518055 Guangdong China School of Materials and Metallurgy Wuhan University of Science andTechnology Wuhan 430081 Hubei China Research and Development Center Wuhan Iron and SteelCorporation Wuhan 430080 Hubei China

Austenite grain sizes in the heat affected zone （HAZ） of a high heat input welded Zr-Ti bearing microal- loyed steel are measured under different welding conditions simulated by a Gleeble-1500 thermal-mechanical simulator. The austenite grain growth is divided into two regimes in terms of temperature. When the temperature is lower than 1 250℃ where the pinning effect of precipitates is strong, the austenite grain size increases slowly with increas- ing peak temperature, but it increases drastically when the temperature is higher than 1 250 ~C where the pinning effect of precipitates is weak. Based on the experimental measurements, an analytical model for predicting the aus- tenite grain size in the heat affected zone is derived. Model predictions indicate that the initial grain size has little effect on the final one, and the grain growth depends mainly on heat input and peak temperature as well as growth activation energy and exponent. With the use of the model, the width of coarse grained heat affected zone （CGHAZ） for a thick plate is predicted.

关键词： welding high heat input microstructure

HIGH-SPEED FLOW EROSION ON A NEW ROLLER COMPACTED CONCRETE DAM DURING CONSTRUCTION

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Journal of Hydrodynamics 2012年第1期24卷 32-38页

作者： WANG Xin LUO Shao-ze HU Ya-an yuan Qiang WANG He-sheng ZHAO Lan-hao Hydraulic Engineering Department Nanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering -Nanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

A new roller compacted concrete dam of Fengman Hydropower Station is to be built in the toe of the old dam,which was identified as a dangerous *** new dam during construction would be influenced by the high-speed flow discharged from the old dam,which is an important problem to be considered for the first time in China,and which would affect the construction of the whole ***,a series of erosion experiments were conducted in this article.A high-speed flow erosion test apparatus was developed for the erosion experiments of the new dam *** maximum jet velocity goes up to 40 m/s and the section area of the nozzle is 0.0025 *** the process of experiments,the equipment shows a good *** wear tests for two types of materials used in the new dam,a roller compacted concrete and a distorted concrete with four kinds of ages were carried out with the flow velocity in the range of 30 m/s-35 m/*** parameters and erosion laws for the two types of concretes with different ages were determined,and a general relationship between the erosion rate and the flow velocity is obtained as：,with the velocity exponent between 3.33 and *** is concluded that the erosion resistance of the distorted concrete is better than that of the roller compacted concrete and the mechanical properties of the concretes of over 14 d age are influenced slightly by the water *** test results might serve as a practical technique guide for the safety of this project during its construction in the flood season.

关键词： high-speed flow impact apparatus erosion test roller compacted concrete hydraulic structures

Radiation dose effects on the morphological development of M_(1) generation pea(Pisum sativum)

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Nuclear Science and Techniques 2021年第11期32卷 63-76页

作者： Da-Peng Xu Hu-yuan Feng Jian-Bin Pan ze-En Yao Jun-Run Wang School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Life Sciences Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China

We irradiated pea seeds with neutrons from a ^(252)Cf source and studied the radiation dose effects on various morphological development parameters during the growth of M_(1) generation *** found that in the dose range of 0.51-9.27 Gy,with the increase in neutron-absorbed dose,the morphological development parameters of M_(1) generation peas at the initial seedling stage showed an obvious trend with three *** the development of pea,this trend gradually *** analysis and verification showed that the main trend in the M_(1) generation of pea seeds was an inhibitory effect induced by neutron irradiation and there was a good linear correlation between the inhibitory effect and neutron absorption dose We successfully demonstrated the background removal of mutant plants and defined morphological developmen parameters for peas that match the overall development of *** results will positively impact neutron mutation breeding and automatic agriculture.

关键词： Neutron irradiation Pea(Pisum sativum) ^(252)Cf source Radiation does effects Absorbed dose Morphological development

Short video preloading via domain knowledge assisted deep reinforcement

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DIGITAL COMMUNICATIONS AND NETWORKS 2024年第6期10卷 1826-1836页

作者： Xie, Yuhong Zhang, yuan Lin, Tao Pan, Zipeng Qian, Si-ze Jiang, Bo Yan, Jinyao Commun Univ China Sch Informat & Commun Engn Beijing 100024 Peoples R China Commun Univ China State Key Lab Media Convergence & Commun Beijing 100024 Peoples R China Shanghai Jiao Tong Univ Sch Elect Informat & Elect Engn Shanghai 200240 Peoples R China

Short video applications like TikTok have seen significant growth in recent years. One common behavior of users on these platforms is watching and swiping through videos, which can lead to a significant waste of bandwidth. As such, an important challenge in short video streaming is to design a preloading algorithm that can effectively decide which videos to download, at what bitrate, and when to pause the download in order to reduce bandwidth waste while improving the Quality of Experience (QoE). However, designing such an algorithm is non-trivial, especially when considering the conflicting objectives of minimizing bandwidth waste and maximizing QoE. In this paper, we propose an end-to-end D eep reinforcement learning framework with A ction M asking called DAM that leverages domain knowledge to learn an optimal policy for short video preloading. To achieve this, we introduce a reward shaping technique to minimize bandwidth waste and use action masking to make actions more reasonable, reduce playback rebuffering, and accelerate the training process. We have conducted extensive experiments using real-world video datasets and network traces including 4G/WiFi/5G. Our results show that DAM improves the QoE score by 3.73%-11.28% compared to state-of-the-art algorithms, and achieves an average bandwidth waste of only 10.27%-12.07%, outperforming all baseline methods.

关键词： Short video preloading Deep reinforcement learning Reward shaping Action masking Domain knowledge

Direct identification of monolayer rhenium diselenide by an individual diffraction pattern

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Nano Research 2017年第7期10卷 2535-2544页

作者： Zhen Fei Bo Wang Ching-Hwa Ho Fang Lin Jun yuan ze Zhang Chuanhong Jin State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China School of Physical Science and Technology Lanzhou University Lanzhou 730000 China Graduate Institute of Applied Science and Technology Taiwan University of Science and Technology Taipei 106 Taiwan China College of Electronic Engineering South China Agricultural University Guangzhou 510642 China Department of Physics University of York Heslington York YO 10 5DD UK

In the current extensive studies of layered two-dimensional （2D） materials, compared to hexagonal structures such as graphene, hBN, and MoS2, low- symmetry 2D materials have shown great potential for applications in anisotropic devices. Rhenium diselenide （ReSe2） possesses the bulk space group P1 and belongs to the triclinic crystal system with a deformed cadmium-iodide-type structure. Here, we propose an electron diffraction-based method to distinguish the monolayer ReSe2 membrane from multilayer ReSe2 and its two different vertical orientations. Our method is also applicable to other low-symmetry crystal systems, including both triclinic and monoclinic lattices, as long as their third unit-cell basis vectors are not perpendicular to the basal plane. Our experimental results are well explained by kinematical electron diffraction theory and the corresponding simulations. Generalization of our method to other 2D materials, such as ~：raphene, is also discussed.

关键词： rhenium diselenide electron diffraction monolayer reciprocal rel-rod

Distribution optimization of circulating water in air-cooled heat exchangers for a typical indirect dry cooling system on the basis of entransy dissipation

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Science China(Technological Sciences) 2015年第4期58卷 617-629页

作者： SUN Jian yuan Kai YANG Li Jun CHEN Lin DU Xiao ze YANG Yong Ping Key Laboratory of Condition Monitoring and Control for Power Plant Equipments of Ministry of Education School of Energy Power and Mechanical Engineering North China Electric Power University

The flow and heat transfer of air-cooled heat exchangers play important roles in the performance of indirect dry cooling systems in power plants,so it is of benefit to the design and operation of a typical indirect dry cooling system to optimize the thermo-flow characteristics of air-cooled heat *** entransy dissipation method is applied to the performance optimization of air-cooled heat exchangers in this *** irreversible heat transfer processes in air-cooled heat exchangers,the heat transfer between circulating water and cooling air and the mixing of circulating water,are taken into account and analyzed by means of the entransy dissipation *** total entransy dissipation rate,which connects the geometrical parameters of air-cooled heat exchanger sectors and the heat capacity rates of the fluids to the heat flow rate in every sector,is *** on the mathematical relation and the conditional extremum method,an optimization equation group is derived,by which the air-cooled heat exchanger with known air-side parameters is optimized,showing that the entransy dissipation based optimization approach can contribute to the distribution optimization of circulating water in air-cooled heat exchangers of a typical indirect dry cooling system.

关键词： indirect dry cooling system air-cooled heat exchanger entransy dissipation optimization

ROS-Responsive Berberine Polymeric Micelles Effectively Suppressed the Inflammation of Rheumatoid Arthritis by Targeting Mitochondria

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Nano-Micro Letters 2020年第6期12卷 138-151页

作者： Xing-xing Fan Meng-ze Xu Elaine Lai-Han Leung Cai Jun Zhen yuan Liang Liu State Key Laboratory of Quality Research in Chinese Medicine Macao Institute For Applied Research in Medicine and HealthMacao University of Science and TechnologyAvenida Wai LongTaipaMacao SARChina Faculty of Health Sciences University of MacaoTaipaMacao SARChina

Rheumatoid arthritis(RA)is an autoimmune disease,which attacks human joint system and causes lifelong inflammatory *** date,no cure is available for RA and even the ratio of achieving remission is very ***,to enhance the efficacy of RA treatment,it is essential to develop novel approaches specifically targeting pathological *** this study,we discovered that RA synovial fibroblasts exhibited higher reactive oxygen species(ROS)and mitochondrial superoxide level,which were adopted to develop ROS-responsive nano-medicines in inflammatory microenvironment for enhanced RA treatment.A selenocystamine-based polymer was synthesized as a ROS-responsive carrier nanoplatform,and berberine serves as a tool *** assembling,ROS-responsive berberine polymeric micelles were fabricated,which remarkably increased the uptake of berberine in RA fibroblast and improved in vitro and in vivo efficacy ten times ***,the anti-RA effect of micelles was blocked by the co-treatment of AMPK inhibitor or palmitic acid,indicating that the mechanism of micelles was carried out through targeting mitochondrial,suppressing lipogenesis and finally inhibiting cellular *** together,our ROS-responsive nano-medicines represent an effective way of preferentially releasing prodrug at the inflammatory microenvironment and improving RA therapeutic efficacy.

关键词： Rheumatoid arthritis Reactive oxygen species Nanoparticles Berberine Oxygen consumption rate