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Dual-polarization two-dimensional valley photonic crystals

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Science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 102-109页

作者： Xin-Tao He jian-Wei Liu Fu-Long Shi Ke Shen Wen-Jie Chen Xiao-dong Chen jian-Wen dong School of Physics State Key Laboratory of Optoelectronic Materials and TechnologiesSun Yat-sen UniversityGuangzhou510275China

The recent realization of valley physics in photonic systems has enriched the topological phases of light with protected edge modes and shown applications in designing high-performance photonic devices. However, the widely reported valley Hall effect of light in two-dimensional systems is limited to one single polarization. Here, we present dual-polarization two-dimensional valley photonic crystals by simultaneously opening two frequency accidental degenerate Dirac cones. Two band gaps with different polarizations are characterized by opposite-valley Chern numbers, which are confirmed by the opposite-phase vortex distributions of bulk modes and opposite Berry curvatures. This situation results in the polarization-dependent refraction of bulk and edge modes, which locate in opposite valleys. The polarization-independent topological valley transport is also demonstrated. Our work shows the flexible control of light in topological photonic systems with a polarization degree of freedom and has applications in polarization multiplexing photonic devices.

关键词： topological photonics valley photonic crystals polarization

Analytical Blowup Solutions to the Compressible Euler Equations with Time-depending Damping

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 568-578页

作者： jian-wei dong Guang-pu LOU Qiao ZHANG Zhengzhou University of Aeronautics Zhengzhou 450015China

In this paper,the analytical blowup solutions of the N-dimensional radial symmetric compressible Euler equations are *** previous results of the blowup solutions for the compressible Euler equations with constant damping are generalized to the time-depending damping *** generalization is untrivial because that the damp coefficient is a nonlinear function of time t.

关键词： compressible Euler equations time-depending damping blowup

Hot deformation behavior of uniform fine-grained GH4720Li alloy based on its processing map

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 83-91页

作者： Qiu-ying Yu Zhi-hao Yao jian-xin dong Beijing Institute of Aeronautical Materials Beijing 100095 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The hot deformation behavior of uniform fine-grained GH4720Li alloy was studied in the temperature range from 1040 to 1130℃ and the strain-rate range from 0.005 to 0.5 s-1 using hot compression testing. Processing maps were constructed on the basis of compression data and a dynamic materials model. Considerable flow softening associated with superplasticity was observed at strain rates of 0.01 s 1 or lower. According to the processing map and observations of the microstructure, the uniform fine-grained microstructure remains intact at 1100℃ or lower because of easily activated dynamic recrystallization （DRX）, whereas obvious grain growth is observed at 1130℃. Metal- lurgical instabilities in the form of non-uniform microstrucmres under higher and lower Zener-Hollomon parameters are induced by local plastic flow and primary γ＇ local faster dissolution, respectively. The optimum processing conditions at all of the investigated strains are pro- posed as 1090-1130℃ with 0.084）.5 s-1 and 0.0054）.008 s-1 and 1040-1085℃ with 0.0054）.06 s-1.

关键词： superalloys hot deformation processing maps microstrucmre superplasticity

Ru-doped phosphorene for electrochemical ammonia synthesis

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Rare Metals 2020年第8期39卷 874-880页

作者： jian-dong Liu Zeng-Xi Wei Yu-Hai Dou Yue-Zhan Feng jian-Min Ma Advanced Catalytic Engineering Research Center of the Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha 410082China Centre for Clean Environment and Energy Gold Coast CampusGriffith UniversityGold Coast QLD 4222Australia Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002China

The electrochemical ammonia synthesis has attracted increasing attention due to its energy saving ***,developing novel electrocatalysts and their mechanism remain great ***,several transition metal(TM)atoms doped on phosphorene were studied as N2 fixation electrocatalysts by using density functional theory(DFT)*** results demonstrate that single Ru atom doped phosphorene shows an excellent catalytic activity for ammonia synthesis via the enzymatic pattern.A small overpotential of 0.696 V is achieved for this *** effect of oxidation in the catalyst was also discussed in our *** deactivates the catalyst,which should be avoided in the *** outcomes offer a novel perspective for single-atom catalytic ammonia synthesis with phosphorene as a substrate.

关键词： Phosphorene Nitrogen reduction reaction Doping Single-atom catalysis Ammonia synthesis

New mechanism to promote long-term T-cell immunity by telomere transfer from antigen-presenting cells

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Cellular & Molecular Immunology 2023年第2期20卷 117-118页

作者： Meiling Jin jian-dong Huang Chinese Academy of Sciences(CAS)Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenChina School of Biomedical Sciences Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulamHong Kong SARChina Department of Clinical Oncology Shenzhen Key Laboratory for Cancer Metastasis and Personalized TherapyThe University of Hong Kong-Shenzhen HospitalShenzhenChina Guangdong-Hong Kong Joint Laboratory for RNA Medicine Sun Yat-Sen University510120GuangzhouChina

Telomeres protect the ends of chromosomes and are important biomarkers of cellular *** mechanism of telomere elongation in T cells is not clear.A recent study revealed that memory CD4+T cells can acquire telomeric DNA transferred via vesicles from antigen-presenting cells,which inhibits T-cell senescence and promotes T-cell expansion and long-lived immunity.

关键词： immunity mechanism transferred

An Adaptive Transmission Scheme in Cooperative Relay Networks with Energy Accumulation

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Chinese Journal of Electronics 2019年第1期28卷 152-161页

作者： TANG Kun SHI Ronghua GUO Yabo SHI Heyuan dong jian School of Information Science and Engineering Central South University School of Insurance and Economics University of International Business and Economics School of Software Tsinghua University

We investigate a wireless-powered cooperative relay network, where an energy constrained relay node accumulates the energy harvested from radio frequency signals, and then assists source signal transmission. An adaptive cooperative transmission scheme for cooperative relay network is developed. The relay helps to transmit the source signal only if it has harvested enough energy and the channels between source and relay do not suffer from an outage. Before each transmission block, one out of two transmission modes, i.e., Half-duplex(HD) or Full-duplex(FD), is dynamically adopted based on the maximal instantaneous capacity of the system. A closed-form expression for the exact outage probability of the system with the proposed scheme is derived. Monte Carlo simulations are run to validate the accuracy of the mathematical analysis, and numerical results show that the proposed protocol outperforms the existing fixed cooperative transmission modes.

关键词： Cooperative relay networks Wireless energy harvesting Full-duplex relaying Half-duplex relaying Outage probability

凝析气藏CO_(2)构造埋存量评估方法研究

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陕西科技大学学报 2025年第1期43卷 101-106页

作者：张铃丰廖新维唐康王晓晨邹建栋中国石油大学(北京)石油工程教育部重点实验室北京102249 中国石油长庆油田分公司陕西西安710018 中国石油塔里木分公司新疆库尔勒841004

凝析气藏中复杂的气液相态变化为CO_(2)埋存潜力评估带来很大困难.为了进一步提高凝析气藏CO_(2)构造埋存量的计算准确性,基于物质的量守恒原理,考虑注入CO_(2)与凝析气体混合、反凝析变化、岩石和束缚水形变等因素,推导了凝析气藏生产... 详细信息

凝析气藏中复杂的气液相态变化为CO_(2)埋存潜力评估带来很大困难.为了进一步提高凝析气藏CO_(2)构造埋存量的计算准确性,基于物质的量守恒原理,考虑注入CO_(2)与凝析气体混合、反凝析变化、岩石和束缚水形变等因素,推导了凝析气藏生产阶段及CO_(2)埋存阶段物质平衡通式,进一步建立了凝析气藏CO_(2)构造埋存量评估方法.结果表明,该方法计算的CO_(2)构造埋存量与数值模拟结果吻合度较好,误差在6.42%以内.忽略混合气体偏差因子变化会导致CO_(2)构造埋存量计算结果偏大,误差达到18.61%.忽略反凝析变化则会导致CO_(2)构造埋存量计算结果偏小,这一误差在低埋存压力区间内高达9.93%.该方法对凝析气藏中CO_(2)构造埋存量评估及CO_(2)埋存方案优化具有重要意义.

关键词：凝析气藏 CO_(2)构造埋存量物质平衡埋存潜力评估

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INVESTIGATION OF INFLUENCE OF WETTABILITY ON POISEUILLE FLOW VIA MOLECULAR DYNAMICS SIMULATION

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Journal of Hydrodynamics 2010年第4期22卷 513-517页

作者： SONG Fu-quan WANG jian-dong College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321004

In this article,the influence of wettability on a liquid flow between two parallel plane walls were studied by using Non-Equilibrium Molecular Dynamics（NEMD） *** wettability of the solid surfaces can be described as the contact *** liquid flow rate,the slip velocity and the slip length which are affected by the contact angle were *** results show that the boundary condition at a microscopic level is different from a ＂no-slip＂ condition at a macroscopic *** exits a slippage of a liquid flow for the hydrophobic boundary and an external force is needed to overcome threshold pressure for the hydrophilic *** the orderly layered distributions of the liquid particles near the hydrophilic surface vary from a place near the hydrophobic *** study indicates that the surface wettability plays a significant role on possibilities of forming a viscous layer and the direct slip at the solid *** resistance of liquid flow can be decreased by changing the wettability of boundary surface.

关键词： molecular dynamics simulation Poiseuille flow hydrophilic surface hydrophobic surface velocity slippage

Minimizing makespan in a two-stage hybrid flow shop scheduling problem with open shop in one stage

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Applied Mathematics(A Journal of Chinese Universities) 2013年第3期28卷 358-368页

作者： dong jian-ming HU Jue-liang CHEN Yong Department of Mathematics Zhejiang Sci-Tech University Institute of Operational Research and Cybernetics Hangzhou Dianzi University

This paper considers a scheduling problem in two-stage hybrid flow shop, where the first stage consists of two machines formed an open shop and the other stage has only one machine. The objective is to minimize the makespan, i.e., the maximum completion time of all jobs. We first show the problem is NP-hard in the strong sense, then we present two heuristics to solve the problem. Computational experiments show that the combined algorithm of the two heuristics performs well on randomly generated problem instances.

关键词： hybrid flow shop open shop Heuristic algorithm.