检索结果-南通市图书馆

Effect of Direct Aging on Corrosion Behavior of AlSi10Mg Alloy Fabricated by Laser Powder Bed Fusion

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 266-282页

作者： Zhen Zhang Zhanyong Zhao Xiaofeng Li Beibei Wang Peikang bai Shanxi Key Laboratory of Controlled Metal Solidification and Precision Manufacturing School of Materials Science and EngineeringNorth University of ChinaTaiyuan030051China Technical Center Taiyuan Iron and Steel(Group)Co.LtdTaiyuan030003China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Effect of direct aging of 170℃on corrosion behavior of laser powder bed fused AlSi10Mg(LPBF-AlSi10Mg)was studied by microstructure analysis,electrochemical analysis and X-ray photoelectron *** results show that direct aging of 170℃has little effect on melt pool and Si cellular structure,but promotes the precipitation of nano-Si particles and releases the residual *** increasing aging time from 0 to 4 h to 24 h,the corrosion property of the LPBF-AlSi10Mg is deteriorated,which is evidenced by increased corrosion current density and decreased pitting potential and polarization *** increasing the aging time,the thickness of the oxide film formed on surface of the LPBF-AlSi10Mg *** Si content of the oxide film of the sample aging for 4 h is the lowest,9.42 at.%,and it is the highest,18.62 at.%,for the sample aging for 24 *** electrochemical noise analysis reveals that the middle-frequency contribution of the Hilbert spectrum is responsible for the deteriorated corrosion performance,which corresponds to metastable pitting initiated by nano-Si particles.

关键词： Laser powder bed fusion AlSi10Mg Direct aging Corrosion

The 2024 M_(j) 7.6 Noto Peninsula, Japan earthquake caused by the fluid flow in the crust

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Research Advances 2024年第3期4卷 1-6页

作者： Yuzo Ishikawa Ling bai Center for Integrated Research and Education of Natural Hazards Shizuoka UniversityShizuoka422-8529Japan State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China

On January 1, 2024 at 16:10:09 JST, an M_(j) 7.6 earthquake struck the Noto Peninsula in the southern part of the Sea of Japan. This location has been experiencing an earthquake swarm for more than three years. Here, we provide an overview of this earthquake, focusing on the slip distribution of the mainshock and its relationship with the preceding swarm. We also reexamined the source areas of other large earthquakes that occurred around the Sea of Japan in the past and compared them with the Matsushiro earthquake swarm in central Japan from1964 to 1968. The difference between the Matsushiro earthquake swarm and the Noto earthquake swarm is the surrounding stress field. The Matsushiro earthquake swarm was a strike-slip stress field, so the cracks in the crust were oriented vertically. This allowed fluids seeped from the depths to rise and flow out to the surface. On the other hand, the Noto area was a reverse fault stress field. Therefore, the cracks in the earth's crust were oriented horizontally. Fluids flowing underground in deep areas could not rise and spread over a wide area in the horizontal plane. This may have caused a large amount of fluid to accumulate underground, triggering a large earthquake. Although our proposed mechanism does not take into account other complex geological conditions into consideration, it may provide a simple way to explain why the Noto swarm is followed by a large earthquake while other swarms are not.

关键词： The M 7.6 Noto Peninsular earthquake Earthquake swarm Fluid triggering Strike-slip fault Reverse fault

Efficient synthesis of forsterite via high-temperature thermochemical reactions from boron mud waste without briquetting

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第4期87卷 124-132页

作者： Fangling Hu Liangliang Fu Qingjin Zhang Guangwen Xu Dingrong bai Key Laboratory on Resources Chermticals and Material of Ministry of Education Sheryang Unfversity of Chemical Technology.Shenyang110142China School of Chemical Engineering University of Science and Technology Liaoning.Anshan 114051China School of Materials Science and Engineering Shenyang University of Technology.Shenyang110142China

Forsterite is a highly demanded material in high-temperature industries due to its superior performance in elevated *** study proposes synthesizing high-quality forsterite via high-temperature thermochemical reactions using abundant boron mud *** new synthesis method capitalizes on the high reactivity of fine raw powder materials,enabling the reaction to reach completion at low temperatures *** chemical characteristics,microscopic morphology,and structure of synthe-sized samples are systematically studied using XRD and *** results confirm that boron mud can be efficiently transformed into forsterite after 10 min of reactions at 1500℃.The synthesized products attain over 98.7%densification and contain more than 85.0%forsterite with well-developed *** activation energy of forsterite grain growth in the 1100-1500℃temperature range is 165.5 kJ/*** study provides a low-cost method for producing forsterite and an efficient and environmentally friendly solution for treating solid waste.

关键词： Fluidized bed Boron mud Forsterite Solid state reaction Activation energy Grain growth

Sawtooth-enhanced bend sensor for gesture recognition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第6期67卷 1727-1736页

作者： bai YanRu ZHANG ZiHang WANG HaoYu GUO Rui LI XiSheng School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China School of Advanced Engineering University of Science and Technology BeijingBeijing100083China School of Precision Instrument and Opto-Electronics Engineering Tianjin UniversityTianjin300072China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China

Gesture recognition has diverse application prospects in the field of human-computer ***,gesture recognition devices based on strain sensors have achieved remarkable results,among which liquid metal materials have considerable advantages due to their high tensile strength and *** improve the detection sensitivity of liquid metal strain sensors,a sawtooth-enhanced bending sensor is proposed in this *** with the results from previous studies,the bending sensor shows enhanced resistance *** addition,combined with machine learning algorithms,a gesture recognition glove based on the sawtooth-enhanced bending sensor is also fabricated in this study,and various gestures are accurately *** the fields of human-computer interaction,wearable sensing,and medical health,the sawtooth-enhanced bending sensor shows great potential and can have wide application prospects.

关键词： liquid metal bending sensor gesture recognition machine learning

Bionic Hand Motion Control Method Based on Imitation of Human Hand Movements and Reinforcement Learning

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第2期21卷 764-777页

作者： Jibo bai Baojiang Li Xichao Wang Haiyan Wang Yuting Guo The School of Electrical Engineering Shanghai DianJi UniversityShanghai201306China

Bionic hands are promising devices for assisting individuals with hand disabilities in rehabilitation *** primarily by bioelectrical signals such as myoelectricity and EEG,these hands can compensate for lost hand ***,developing model-based controllers for bionic hands is challenging and time-consuming due to varying control parameters and unknown application *** address these challenges,we propose a model-free approach using reinforcement learning(RL)for designing bionic hand *** method involves mimicking real human hand motion with the bionic hand and employing a human hand motion decomposition technique to learn complex motions from simpler *** approach significantly reduces the training time *** utilizing real human hand motion data,we design a multidimensional sampling proximal policy optimization(PPO)algorithm that enables efficient motion control of the bionic *** validate the effectiveness of our approach,we compare it against advanced baseline *** results demonstrate the quick learning capabilities and high control success rate of our method.

关键词： Bionic hand Reinforcement learning Motion decomposition Multidimensional sampling PPO algorithm

Nonreciprocal thermal metamaterials:Methods and applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1678-1693页

作者： Zhengjiao Xu Chuanbao Liu Xueqian Wang Yongliang Li Yang bai Institute for Advanced Material and Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Nonreciprocity of thermal metamaterials has significant application prospects in isolation protection,unidirectional transmission,and energy ***,due to the inherent isotropic diffusion law of heat flow,it is extremely difficult to achieve nonreciprocity of heat *** review presents the recent developments in thermal nonreciprocity and explores the fundamental theories,which underpin the design of nonreciprocal thermal metamaterials,i.e.,the Onsager reciprocity ***,three methods for achieving nonreciprocal metamaterials in the thermal field are elucidated,namely,nonlinearity,spatiotemporal modulation,and angular momentum bias,and the applications of nonreciprocal thermal metamaterials are *** also discuss nonreciprocal thermal ***,the potential applications of nonreciprocity to other Laplacian physical fields are ***,the prospects for advancing nonreciprocal thermal metamaterials are highlighted,including developments in device design and manufacturing techniques and machine learning-assisted material design.

关键词： thermal metamaterials nonreciprocity nonlinearity spatiotemporal modulation

Effect of operational and geometric parameters on the hydrodynamics of a Wurster coater:A CFD-DEM study

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第2期85卷 62-76页

作者： Yinqiang Song Tuo Zhou Ruiqi bai Man Zhang Hairui Yang Department of Energy and Power Engineering Tsinghua UniversityBeijing100084China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Tsinghua UniversityBeijing100084China State Key Laboratory of Power System and Generation Equipment Tsinghua UniversityBeijing100084China

A coupled CFD-DEM method was used to study the hydrodynamics of a Wurster ***,the CFD part of the model was validated by the accurate prediction of the pressure drops over a pseudo-2D fluidized bed under various gas *** effect of gas velocity,gap height,tube length and batch volume of the particles on the cycle time and the residence time of the particles was thoroughly *** central jet gas velocity ui was found to speed up the particle cycle but undermine the coating *** gas velocity at the horizontal transport zone u2 was able to promote the horizontal transport of the particles but should not be too high,otherwise,it would obstruct the normal falling back of the particles in the downward *** gap heights would decrease the coating efficiency but tube length had little impact on *** increment of batch volume would commonly abase the cycle time and the working efficiency under a given *** de-fluidization problem arose when the batch volume increased to 550 ***,this problem could be swept out by the optimization of u1 and *** a mixture of different sizes,the coarse particles enjoyed higher coating efficiency and could travel closer to the *** may shield the fine particles from getting enough coating liquids,and thus coarse particles and fine particles were not recommended to get coated in the same batch.

关键词： Numerical simulation CFD-DEM Wurster coater Hydrodynamics Cycle time Residence time

Energy-absorbing porous materials:Bioinspired architecture and fabrication

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第2期17卷 679-690页

作者： Junheng Zhao Meng Li Jiewei Chen Weiwei Gao Hao bai State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310058China

Energy-absorbing materials are widely used in transportations,sports,and the military ***,porous materials,including natural and artificial materials,have attracted tremendous attentions due to their light weight and excellent energy absorption *** review summarizes the recent progresses in the natural and artificial energy-absorbing porous ***,we review the typical natural porous materials including cuttlebone,bighorn sheep horn,pomelo peel,and sunflower stem *** architectures,energy absorption abilities,and mechanisms of these typical natural materials and their bioinspired materials are ***,we provide a review on the fabrication methods of artificial energy-absorbing porous materials,such as conventional foaming and three-dimensional(3D)***,we address the challenges and prospects for the future development of energy-absorbing porous *** importantly,our review provides a direct guidance for the design and fabrication of energy-absorbing porous materials required for various engineering applications.

关键词： energy-absorbing porous materials natural materials natural structures bioinspired materials

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-Yi Yuan Dong bai Zhen Wang Zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process