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Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1364-1372页

作者： Xu Yang Dezhi chen Li Feng Gang Qin shiping Wu Ruirun chen National Key Laboratory for Precision Hot Processing of Metals School of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were explored.Results show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)phases.As W content increases,the microstructure changes from eutectic to dendritic.The addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC phase.Tensile results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening mechanisms.The yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and plasti-city.The fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC phase.The eutectic lamellar structure impedes crack propagation and maintains plasticity.

关键词： high-entropy alloy microstructure mechanical property fracture behavior

Numerical Investigation of the Angle of Attack Effect on Cloud Cavitation Flow around a Clark-Y Hydrofoil

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2947-2964页

作者： Di Peng Guoqing chen Jiale Yan shiping Wang College of Engineering Peking UniversityBeijing100871China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehicles.The re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity instability.Concurrently,these phenomena significantly modulate the evolution of cavitation flow.In this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM framework.Comparative analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction force.These results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.

关键词： Cloud cavitation re-entrant jet compression wave clark-Y hydrofoil

Nucleus-targeting orange-emissive carbon dots delivery adriamycin for enhanced anti-liver cancer therapy

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Chinese Chemical Letters 2024年第6期35卷 421-426页

作者： Qiang Li Jiangbo Fan Hongkai Mu Lin chen Yongzhen Yang shiping Yu The Second Hospital of Shanxi Medical University Taiyuan 030001China Shanxi Medical University Taiyuan 030001China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China

Carbon dots(CDs)with precise targeting function show great potential in the field of drug delivery therapeutics.In this study,the functionalized nucleus-targeting orange-emissive CDs with nuclear localization sequence(NLS)were loaded with adriamycin(DOX)to obtain a nucleus-targeting orange-emissive CDs drug delivery system(CDs-NLS-DOX),which delivered DOX to tumor cell nuclei to enhance its anti-tumor activity.The drug carrier orange-emissive CDs showed excitation-independent behavior,stable and enhanced imaging capability and good biocompatibility in vitro and in vivo.Meanwhile,the CDs-NLS could target the nuclei efficiently,and the CDs-NLS-DOX complexes had a high drug loading rate(59.4%)after loading DOX,exhibiting p H-dependent DOX release behavior through breaking acylhydrazone bond in a weak acidic environment.In addition,the CDs-NLS-DOX complexes exhibited an enhanced killing activity against human hepatoma cells(HepG2).The in vivo therapeutic effects on HepG2 nude mice transplanted tumors indicated the CDs-NLS-DOX had a stronger ability to inhibit tumor growth compared to free DOX.In short,CDs-NLS-DOX is expected to be a precise and efficient nucleus-targeting nano-drug delivery system for tumor treatment.

关键词： Carbon dots Nucleus-targeting Adriamycin Drug delivery system Liver cancer therapy

Carbon and water fluxes in ecologically vulnerable areas in China

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Journal of Plant Ecology 2022年第5期15卷 879-881页

作者： Zhongmin Hu shiping chen Yanbin Hao Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province Hainan UniversityHaikou 570228China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519082China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Ecologic vulnerable areas(EVAs)are the regions where ecosystems are fragile and vulnerable to sufferfrom degradation with external disturbances,e.***.environmental changes and human activities(Fengetal.2022;Wangetal.2019).EVAsinChina are widely distributed and account for more than 55%China's landarea(Ministryof Ecologyand Environment of the People's Republic of China 2008).Theecosystem in EVAs,chartered with low stability,weak resistance and high vulnerability,has been experiencing significant degradation owing to the impacts of global climate change and human activities(Bai et al.2018;chen et al.202l;Yuetal.2022).

关键词： al. vulnerable degradation

Transactional Network Analysis and Money Laundering Behavior Identification of Central Bank Digital Currency of China

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Journal of Social Computing 2022年第3期3卷 219-230页

作者： Ziyu Li Yanmei Zhang Qian Wang shiping chen School of Information Central University of Finance and EconomicsBeijing 100081China the Global Anti-Money Laundering Center Agricultural Bank of ChinaBeijing 100005China the CSIRO Data61 Sydney 1710Australia.E-mail:shiping.chen@data61.csiro.au.

With the gradual application of central bank digital currency(CBDC)in China,it brings new payment methods,but also potentially derives new money laundering paths.Two typical application scenarios of CBDC are considered,namely the anonymous transaction scenario and real-name transaction scenario.First,starting from the interaction network of transactional groups,the degree distribution,density,and modularity of normal and money laundering transactions in two transaction scenarios are compared and analyzed,so as to clarify the characteristics and paths of money laundering transactions.Then,according to the two typical application scenarios,different transaction datasets are selected,and different models are used to train the models on the recognition of money laundering behaviors in the two datasets.Among them,in the anonymous transaction scenario,the graph convolutional neural network is used to identify the spatial structure,the recurrent neural network is fused to obtain the dynamic pattern,and the model ChebNet-GRU is constructed.The constructed ChebNet-GRU model has the best effect in the recognition of money laundering behavior,with a precision of 94.3%,a recall of 59.5%,an F1 score of 72.9%,and a microaverage F1 score of 97.1%.While in the real-name transaction scenario,the traditional machine learning method is far better than the deep learning method,and the micro-average F1 score of the random forest and XGBoost models both reach 99.9%,which can effectively identify money laundering in currency transactions.

关键词： central bank digital currency(CBDC) transactional network money laundering behavior identification

光响应基因BcCfaS通过脂质代谢调控灰葡萄孢菌的光形态建成及致病力

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Engineering 2024年第4期35卷 201-213页

作者： Guangjin Li Zhanquan Zhang Yong chen Tong chen Boqiang Li shiping Tian Key Laboratory of Plant Resources The Innovative Academy of Seed DesignInstitute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Light is a fundamental environmental factor for living organisms on earth—not only as a primary energy source but also as an informational signal.In fungi,light can be used as an indicator for both time and space to control important physiological and morphological responses.Botrytis cinerea(B.cinerea)is a devastating phytopathogenic fungus that exploits light cues to optimize virulence and the balance between conidiation and sclerotia development,thereby improving its dispersal and survival in ecosystems.However,the components and mechanisms underlying these processes remain obscure.Here,we identify a novel light-signaling component in B.cinerea,BcCfaS,which encodes a putative cyclopropane fatty-acyl-phospholipid synthase.BcCfaS is strongly induced by light at the transcriptional level and plays a crucial role in regulating photomorphogenesis.Deletion of BcCfaS results in reduced vegetative growth,altered colony morphology,impaired sclerotial development,and enhanced conidiation in a lightdependent manner.Moreover,the mutant exhibits serious defects in stress response and virulence on the host.Based on a lipidomics analysis,a number of previously unknown fungal lipids and many BcCfaS-regulated lipids are identified in B.cinerea,including several novel phospholipids and fatty acids.Importantly,we find that BcCfaS controls conidiation and sclerotial development by positively regulating methyl jasmonate(MeJA)synthesis to activate the transcription of light-signaling components,revealing for the first time the metabolic base of photomorphogenesis in fungi.Thus,we propose that BcCfaS serves as an integration node for light and lipid metabolism,thereby providing a regulatory mechanism by which fungi adapt their development to a changing light environment.These new findings provide an important target for antifungal design to prevent and control fungal disease.

关键词： Light Botrytis cinerea Cyclopropane fatty-acyl-phospholipid synthase Lipid metabolism Photomorphogenesis Virulence

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以发展农业新质生产力推进农业强国建设

农业经济问题 2024年第4期 36-46页

作者：毛世平张琛中国农业科学院农业经济与发展研究所北京100081 中国社会科学院人口与劳动经济研究所北京100006

发展农业新质生产力为建设农业强国提供了新的动能。农业新质生产力的重点是“新”和“质”,“新”表现为技术应用新、产业业态新、发展模式新、价值创造新,“质”表现为生产力的质态新和质效新。发展农业新质生产力是对马克思主义基本... 详细信息

发展农业新质生产力为建设农业强国提供了新的动能。农业新质生产力的重点是“新”和“质”,“新”表现为技术应用新、产业业态新、发展模式新、价值创造新,“质”表现为生产力的质态新和质效新。发展农业新质生产力是对马克思主义基本原理中生产力和生产关系理论的遵循与延伸,是对传统农业生产力的一脉相承,也是加快实现高水平科技自立自强、应对农村人口结构快速转变和加快建设农业强国的现实需要。农业新质生产力依托科技创新和质态创新的路径推动了以农业全要素生产率提升为代表的农业质效提升,助力农业强国建设。数字技术、育种技术、农机装备技术、合成生物技术将是农业新质生产力的主要实践应用场景。未来,以发展农业新质生产力推进农业强国建设需要加快农业科技创新步伐、全面实施“数据要素×现代农业”行动、加快农机智能装备技术提档升级、前瞻性布局未来产业在农业中应用、加快农业发展方式绿色转型和加强农业科技性人才队伍建设。

关键词：新质生产力农业强国技术进步数字化

Ultralow cross talk arrayed waveguide grating integrated with tunable microring filter array

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Chinese Optics Letters 2024年第3期22卷 50-54页

作者：胡鹤鸣刘世平李天文范永杰陈华方青 College of Science Kunming University of Science and TechnologyKunming 650093China College of Electronic Science and Engineering Jilin UniversityJilin 130012China

The silicon-based arrayed waveguide grating(AWG)is widely used due to its compact footprint and its compatibility with the mature CMOS process.However,except for AWGs with ridged waveguides of a few micrometers of cross section,any small process error will cause a large phase deviation in other AWGs,resulting in an increasing cross talk.In this paper,an ultralow cross talk AWG via a tunable microring resonator(MRR)filter is demonstrated on the SOI platform.The measured insertion loss and minimum adjacent cross talk of the designed AWG are approximately 3.2 and-45.1 d B,respectively.Compared with conventional AWG,its cross talk is greatly reduced.

关键词： SOI platform arrayed waveguide grating cross talk microring filter array thermo-optic effect

青藏高原高寒植物对生长季偶发性霜冻事件表现出深度过冷却现象

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Journal of Plant Ecology 2024年第3期17卷 84-94页

作者： Ji Suonan Wangwang Lü Aimée TClassen Wenying Wang Ben La Xuwei Lu Cuo Songzha chenghao chen Qi Miao Fanghui Sun Lhamo Tsering shiping Wang College of Life Sciences Qinghai Normal UniversityXining 810016China Key Laboratory of Biodiversity Formation Mechanism and Comprehensive Utilization of the Qinghai-Tibet Plateau in Qinghai Province Xining 810016China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchBeijing 100101China Department of Ecology and Evolutionary Biology University of MichiganMI 48109USA

气候变暖促进了植物的春季物候,打破了气候与植物生长之间原有的平衡。随着极端气候事件出现更加频繁,气候与植物生长之间的不匹配性会影响植物的生存、生长和繁殖。为了防止生长季节在细胞内结冰,植物会采用过冷却策略。然而,气候事件... 详细信息

气候变暖促进了植物的春季物候,打破了气候与植物生长之间原有的平衡。随着极端气候事件出现更加频繁,气候与植物生长之间的不匹配性会影响植物的生存、生长和繁殖。为了防止生长季节在细胞内结冰,植物会采用过冷却策略。然而,气候事件的严重程度和物候期可能会影响植物在霜冻事件后的恢复。本研究通过实验探究了4种不同严重程度的极端霜冻事件如何影响青藏高原上两种优势物种钉柱委陵菜(Potentilla saundersiana,仲夏开花)和小龙胆(Gentiana parvula,夏末开花)的过冷却点和枯黄期。探讨了物候期如何影响钉柱委陵菜对霜冻事件的反应。结果发现,两个物种在遭受霜冻损害时都表现出过冷现象。钉柱委陵菜的平均过冷却点为−6.9℃,并受最低温度、持续时间和物候期的影响,而小龙胆的平均过冷却点为−4.8℃,最低温度和持续时间对其过冷却点影响不显著。此外,两个物种在最低温度(−10℃)处理持续4小时后均快速枯黄。本研究首次探索并定量了青藏高原高寒植物的过冷却点。鉴于高寒植物遭遇霜冻事件的概率不断增加,上述结果对了解高寒植物的生长和生存如何应对极端气候的不利影响具有重要意义。

关键词：气候变化极端霜冻事件过冷却现象物候期枯黄