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Sintering Formation of Low Temperature Phase MnBi and Its Disordering in Mechanical Milling

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Journal of Materials Science & Technology 1996年第5期12卷 335-341页

作者： Yin, FX gu, nj Shigematsu, T Nakanishi, N KONAN UNIV FAC SCIDEPT CHEMKOBE 658JAPAN

With X-ray diffraction and DSC analysis, it is found that 4 cycles of sintering at 593 K are necessary for the complete production of the low-temperature phase (LTP) MnBi. The c/a of the fabricated LTP MnBi is 1.4286. Metastable phase MnBip formed in primary sintering stage of LTP MnBi has the similar crystal structure and lattice constant with the quenched high-temperature phase (HTP) Mn1.08Bi. The structural differences between MnBip phase and Mn1.08Bi phase are discussed. The LTP MnBi phase is unstable for strong mechanical milling as Bi appears after milling over 7200 s in the present milling condition. Strains caused by the mechanical attrition are difficult to accumulate in the MnBi crystals, and the crystal size of the milled MnBi is only 30 nm before the presence of grains coalescence. The whole milling process can be classified into 3 stages indicated by the structural changes. Based on the structural parameter calculation, the changes of atomic configurations in every stage have been discussed. The existence of Bi equivalent vacancy site is considered to play an important role in the disordering processes of Mn and Bi atoms.

关键词： Binary alloys

Aging Effect on Configuration of Dislocations in Parent Phase of a Thermomechanically Trained Cu-Zn-Al Alloy

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Journal of Materials Science & Technology 1995年第6期11卷 415-417页

作者： ZHANG, QG GAO, JS gu, nj YIN, FX HEBEI INST TECHNOL TIANJIN 300130PEOPLES R CHINA

With electron microscopic investigation, the configuration of dislocations in an aged Cu-25.72Zn-4.21Al (wt-%) shape memory alloy was found to be in the form of superdislocations and their jogs, which were different from the preferential dislocations regularly aligned in an unaged alloy. These defects generated during aging treatment were considered to be responsible for low fatigue life.

关键词： Copper alloys

The Inherent Law of the Unpredictability of Financial Asset Price Fluctuations: Multistability and Chaos

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Journal of Systems Science & Complexity 2024年第2期37卷 776-804页

作者： gu Enguo Huanghe University of Science and Technology Zhengzhou 450006China

This paper aims at understanding the price dynamics generated by the interaction of traders relying on heterogeneous expectations in an asset pricing *** the present work the authors analyze a financial market populated by five types of boundedly rational speculators-two types of fundamentalists,two types of chartists and trend followers which submit buying/selling orders according to different trading *** authors formulate a stock market model represented as a 2 dimensional piecewise linear discontinuous *** proposed contribution to the existing financial literature is two ***,the authors perform study of the model involving a 2 dimensional piecewise linear discontinuous map through a combination of qualitative and quantitative *** authors focus on the existence conditions of chaos and the multi-stability regions in parameter *** border collision bifurcation curves and basins of multi-attractors are also *** authors find that chaos or quasi-period exists only in the case of fixed point being a saddle(regular or flip)and that the coexistence of multiple attractors may exist when the fixed point is an attractor,but it is common for spiral and flip fixed points.

关键词： BCB curve chaos financial market heterogeneous agents multiple attractors piecewise linear discontinuous map

Ultra-simplified diffraction-based computational spectrometer

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Light(Science & Applications) 2024年第6期13卷 1022-1031页

作者： Chuangchuang Chen Honggang gu Shiyuan Liu State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhanHubei430074China Optics Valley Laboratory WuhanHubei430074China

Miniaturizing spectrometers for compact and cost-effective mobile platforms is a major challenge in current spectroscopy research,where conventional spectrometers are impractical due to their bulky *** miniaturized designs primarily rely on precalibrated response functions of nanophotonic structures to encode spectral information captured in a snapshot by detector *** spectrum reconstruction is achieved through computational techniques,but this requires precise component design,high-precision fabrication,and *** propose an ultra-simplified computational spectrometer that employs a one-to-broadband diffraction decomposition strategy facilitated by a numerical regularized transform that depends only on the spectrum of the diffracted *** key feature of our design is the use of a simple,arbitrarily shaped pinhole as the partial disperser,eliminating the need for complex encoding designs and full spectrum *** spectrometer achieves a reconstructed spectral peak location accuracy of better than 1 nm over a 200 nm bandwidth and excellent resolution for peaks separated by 3 nm in a bimodal spectrum,all within a compact footprint of under half an ***,our approach also reveals a breakthrough in broadband coherent diffractive imaging without requiring any prior knowledge of the broadband illumination spectrum,assumptions of non-dispersive specimens,or correction for detector quantum efficiency.

关键词： simplified spectrum illumination

An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation

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Defence Technology（防务技术） 2024年第2期32卷 254-261页

作者： Benfeng gu Haiyuan Li Baoming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China

To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore *** this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried *** test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of *** the simulation results and experimental data,the damage condition of the contact surface is analyzed.

关键词： Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1661-1667页

作者： gu-jun Chen Sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

A Comparison of Four Neural Networks Algorithms on Locomotion Intention Recognition of Lower Limb Exoskeleton Based on Multi-source Information

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Journal of Bionic Engineering 2024年第1期21卷 224-235页

作者： Duojin Wang Xiaoping gu Hongliu Yu Institute of Rehabilitation Engineering and Technology University of Shanghai for Science and Technology516 Jungong RoadShanghai 200093China Shanghai Engineering Research Center of Assistive Devices 516 Jungong RoadShanghai 200093China

Lower Limb Exoskeletons(LLEs)are receiving increasing attention for supporting activities of daily *** such active systems,an intelligent controller may be *** this paper,we proposed a locomotion intention recognition system based on time series data sets derived from human motion *** of input data and Deep Learning(DL)algorithms,this framework enables the detection and prediction of users’movement *** makes it possible to predict the detection of locomotion modes,allowing the LLEs to provide smooth and seamless *** pre-processed eight subjects were used as input to classify four scenes:Standing/Walking on Level Ground(S/WOLG),Up the Stairs(US),Down the Stairs(DS),and Walking on Grass(WOG).The result showed that the ResNet performed optimally compared to four algorithms(CNN,CNN-LSTM,ResNet,and ResNet-Att)with an approximate evaluation indicator of 100%.It is expected that the proposed locomotion intention system will significantly improve the safety and the effectiveness of LLE due to its high accuracy and predictive performance.

关键词： Lower limb exoskeletons(LLEs) Locomotion intention ResNet Multi-source

Evaluating the historical,clinical,and cultural value of the Tian Hui Yi Jian

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Journal of Traditional Chinese Medicine 2024年第1期44卷 220-221页

作者： YU Linyong gu Man China Academy of Chinese Medical Sciences Beijing 100700China Institute for History of Medicine and Medical Literature China Academy of Chinese Medical SciencesBeijing 100700China

Tian Hui Yi Jian was compiled by the Tianhui Medical Manuscripts Compilation Group,which includes scholars from the Institute for History of Medicine and Medical Literature of the China Academy of Chinese Medical Sciences(CACMS),Chengdu University of Traditional Chinese Medicine,Chengdu Institute of Cultural Relics and Archaeology,and Jingzhou Cultural Relics Protection *** was published by the Cultural Relics Press in November *** volume includes images of eight medical manuscripts,along with the Team's annotations,and photographs of a lacquered figurine with meridian-channels and words on its surface.

关键词： surface Chengdu Tian

Stacking MoS_(2) flower-like microspheres on pomelo peels-derived porous carbon nanosheets for high-efficient X-band electromagnetic wave absorption

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Nano Research 2024年第3期17卷 1607-1615页

作者： Jia Zhao Zhe gu Qingguo Zhang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China

The key to solve increasingly severe electromagnetic(EM)pollution is to explore sustainable,easily prepared,and cost-effective EM wave absorption materials with exceptional absorption ***,instead of anchoring on carbon materials in single layer,MoS_(2) flower-like microspheres were stacked on the surface of pomelo peels-derived porous carbon nanosheets(C)to fabricate MoS_(2)@C nanocomposites by a facile solvothermal *** wave absorption performances of MoS_(2)@C nanocomposites in X-band were systematically investigated,indicating the minimum reflection loss(RLmin)of-62.3 dB(thickness of 2.88 mm)and effective absorption bandwidth(EAB)almost covering the whole X-band(thickness of 2.63 mm)with the filler loading of only 20 wt.%.Superior EM wave absorption performances of MoS_(2)@C nanocomposites could be attributed to the excellent impedance matching characteristic and dielectric loss capacity(conduction loss and polarization loss).This study revealed that the as-prepared MoS_(2)@C nanocomposites would be a novel prospective candidate for the sustainable EM absorbents with superior EM wave absorption performances.

关键词： pomelo peels-derived porous carbon nanosheets(C) MoS_(2)@C nanocomposites stacked structure electromagnetic(EM)wave absorption