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A primary study on biological behavior of aluminum using^26Al-AMS

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Nuclear Science and Techniques 2016年第3期27卷 25-30页

作者： Song-Mei Qin xiang-Gao Wang Xiao-Xi Lan Yun-Ting Gu Ke-jun Dong Ming He shan Jiang Guangxi University of Chinese Medicine Nanning 530001China GXU-NAOC Center for Astrophysics and Space Sciences Department of PhysicsGuangxi UniversityNanning 530004China Guangxi Key Laboratory for the Relativistic Astrophysics Nanning 530004China China Institute of Atomic Energy Beijing 102413China

Aluminum is concerned as a possible cause of many *** investigate the long-term A1 biokinetics and bioavailability in various kinds of Al-contained medicine and food,an accelerator mass spectrometry(AMS)based on the HI-13 tandem has been established for biological analysis with ^(26)A1(T_(1/2) = 716,000 years) as the *** this paper,the animal tracing,sample preparation procedure and ^(26)A1-AMS measurement are *** sample preparation procedure has been simplified.A high sensitivity of 5×10^(-15) for ^(26)A1/^(27)A1 has been *** phases were found before and after a break time(t_b)for the ^(26)A1 retained in blood and brain,with t_b≈8 and12 h after the ^(26)Al tracer injection,respectively.

关键词： AMS 生物学特性铝制备过程生物利用度生物动力学加速器质谱生物分析

22Cr High-Mn-N Low-Ni Economical Duplex Stainless Steels

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Journal of Iron and Steel Research International 2012年第2期19卷 50-56页

作者： JIANG Da-wei GE Chang-sheng ZHAO xiang-juan LI jun SHI Lu-lu XIAO Xue-shan Institute of Materials Shanghai University Shanghai 200072 China Jiangsu JosenSpecial Steel Products Co Ltd Xinghua 225721 Jiangsu China

A new family of economical duplex stainless steels in which N or Mn was substituted for Ni with composi- tion of 22Cr-8.0Mn-xNi-1.0Mo-0.7Cu-0.7W-0.3N （x = 0.5 -- 2.0） have been developed by examining the micro- structure, mechanical and corrosion properties of these alloys. The results show that these alloys have a balanced ferrite-austenite relation. In addition, the alloys are free of precipitation of sigma phase and Cr-nitride when solution- treated at 750 to 1300℃ for 30 min. The yield strength, tensile strength and fracture elongation values of experi- mental alloys solution-treated at 1050 ℃ for 30 min are about 500, 750 MPa and 40.0%, respectively. Low-temper- ature impact properties can be improved distinctly with the increase of nickel content. Among the designed DSS al- loys, the alloy with Ni of 2.0% is found to be an optimum alloy with proper phase proportion, better low-tempera- ture impact properties and higher pitting corrosion resistance compared with those o~ other alloys. The mechanical and corrosion properties and lower production cost of the designed DSSs are better than those of AISI 304.

关键词： economical duplex stainless steel low-temperature impact property pitting corrosion resistance

A New Resource-Saving,High Chromium and Manganese Super Duplex Stainless Steels 29Cr-12Mn-2Ni-1Mo-xN

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Journal of Iron and Steel Research International 2011年第9期18卷 41-46页

作者： MA Zheng-huan ZHAO xiang-juan GE Chang-sheng DING Tie-suo LI jun XIAO Xue-shan Institute of Materials Shanghai University Shanghai 200072 China Jiangsu Josen Special Steel Products Co Ltd Xinghua 225721 Jiangsu China

A new family of resource saving, high chromium and manganese super duplex stainless steels （DSSs）, with a composition in mass percent, % of Cr 0.29, Mn 0.12, Ni 2.0, Mo i. 0, and N 0. 51-0. 68, has been developed by examining the effect of N on the microstructure, mechanical properties and corrosion properties. The results show that these alloys have a balanced ferrite-austenite relation. The austenite volume fraction decreases with the solution treatment temperature, but it increases with an increase in N content. The increases in nitrogen enhance the ultimate tensile strength （UTS） and reduce the ductility of the material slightly. The pitting corrosion potential increases first and then decreases with an increase in nitrogen content when the amount of N arrives to 0.68%. The yield stress and ultimate tensile strength of solution treated samples were more than 680 and 900 MPa, the elongation of experimental alloys are higher than 30%, respectively, what is more, the pitting potentials were beyond 1 100 mV.

关键词： duplex stainless steel microstructure mechanical property pitting potential

In situ XAFS Investigation on Zincblende ZnS up to 31.7 GPa

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Chinese Physics Letters 2013年第4期30卷 129-132页

作者： YANG jun ZHU Feng ZHANG Qian WU Ye WU xiang QIN shan DONG jun-Cai CHEN Dong-Liang Key Laboratory of Orogenic Belts and Crustal Evolution(Ministry of Education and School of Earth and Space SciencesPeking UniversityBeijing 100871 Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049

In situ high-pressure x-ray absorption fine structure(EXAFS)measurements on the Zn K-edge in zincblende ZnS are performed up to 31.7 GPa at room temperature using a synchrotron radiation x-ray re-focused by a polycapillary half-lens in the classic energy-scanning transmission *** present XAFS data illustrate that ZnS undergoes a phase transition from zincblende F43m to rocksalt Fm3m at 16.9 GPa,accompanied by the increase of the first shell coordination number of the absorption zinc atoms and the unit-cell volume collapse of~14%.The isothermal equation of state of the F43m ZnS is well presented by the third-order Birch–Murnaghan equation of state with V0=158.6±0.8?3,B0=87±5 GPa and B0'=4(fixed).The high-pressure behavior of ZnS from the XAFS spectra is consistent with the previous high-pressure XRD *** addition,the present experimental method demonstrates that the large divergent x-ray micro-beam induced by a polycapillary half-lens can suppress effectively the glitches from single crystal diamond anvil and improve significantly the quality of the XAFS data,which will shed light on the high-pressure XAFS applications.

关键词： XAFS absorption capillary

Resource allocation with minimum transmit power in multicast OFDM systems

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Journal of Systems Engineering and Electronics 2010年第3期21卷 355-360页

作者： Bo Wu jun Shen Haige xiang School of Electronics Engineering and Computer Science Peking University Beijing 100871 R R. China

To minimize the total transmit power for multicast service in an orthogonal frequency division multiplexing（OFDM） downlink system,resource allocation algorithms that adaptively allocate subcarriers and bits are *** proposed algorithms select users with good channel conditions for each subcarrier to reduce the transmit power,while guaranteeing each user＇s instantaneous minimum rate *** resource allocation problem is first formulated as an integer programming（IP） problem,and then,a full search algorithm that achieves an optimal solution is *** reduce the computation load,a suboptimal algorithm is *** suboptimal algorithm decouples the joint resource allocation problem by separating subcarrier and bit ***-like algorithms are employed in both *** results illustrate that the proposed algorithms can significantly reduce the transmit power compared with the conventional multicast approach and the performance of the suboptimal algorithm is close to the optimum.

关键词： resource allocation multicast orthogonal frequency division multiplexing (OFDM) integer programming (IP) greedy algorithm.

Effect of high magnetic field on solidification microstructure evolution of a Cu-Fe immiscible alloy

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China Foundry 2022年第4期19卷 335-341页

作者： Yu-jie Yan Chen Wei Yi-xuan He Chao Li Ping-xiang Zhang Jin-shan Li jun Wang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Xi'an Superconducting Magnet Technology Co. Ltd.Xi'an 710018China Northwest Institute for Nonferrous Metal Research Xi'an 710016China

The liquid phase separation behavior and the evolution of the solidification microstructure of a binary Cu_(50)Fe_(50) alloy were investigated under the conditions of without and with a 10 T magnetic field,with different undercooling during the solidification *** show that the combined effect of Stokes motion and Marangoni convection leads to the formation of the core-shell structure under the condition without the magnetic *** addition,specific gravity segregation is reinforced by increasing the undercooling,resulting in Fe-rich phase drifts towards the sample *** the 10 T magnetic field,the Fe-rich phase is elongated in the parallel direction of the magnetic field under the action of demagnetization energy due to the difference of static magnetic energy and surface *** the vertical direction,through the action of Lorentz force,the convection in the melt is inhibited and Fe-rich phase becomes more ***,the diffusion of the two phases and the coagulation of the Fe-rich phases are also restrained under the magnetic field,therefore,the phase volume fraction of the Fe-rich phase decreases at the same undercooling in the 10 T magnetic *** magnetic field inhibits the segregation behavior in the vertical direction of the magnetic field,and at the same time,improves the gravitational segregation to a certain extent,which has a very important impact on microstructure regulation.

关键词： high magnetic field Cu-Fe immiscible alloy undercooling solidification

Analysis of structural response under blast loads using the coupled SPH-FEM approach

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1184-1192页

作者： jun-xiang XU Xi-la LIU Department of Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

A numerical model using the coupled smoothed panicle hydrodynamics-finite element method （SPH-FEM） approach is presented for analysis of structures under blast loads. The analyses on two numerical cases, one for free field explosive and the other for structural response under blast loads, are performed to model the whole processes from the propagation of the pressure wave to the response of structures. Based on the simulation, it is concluded that this model can be used for reasonably accurate explosive analysis of structures. The resulting information would be valuable for protecting structures under blast loads.

关键词： Smoothed particle hydrodynamics (SPH) Finite element method (FEM) Reinforced concrete structure Explosion

Effects of Alloy Elements on Oxidation Resistance and Stress-Rupture Property of P92 Steel

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 129-138页

作者： Gang Liu Yu-Lai Xu Cai-Xiong Yang Xue-shan Xiao Xi-Min Chen Xiao-Ke Zhang xiang-jun Meng Laboratory for Microstructures Institute of Materials Shanghai University Baosteel Special Materials Co. Ltd

Effects of alloy elements Cr, W, Ce, and Si on oxidation behavior at 750℃ in air and stress-rupture properties of P92 steel have been investigated. The proper increase in elements Cr, W, and Ce improved to varying degrees both oxidation resistance by either facilitating more protective Cr2O3 or modifying surface morphologies and stress-rupture life largely attributed to the formation of fine Laves phase. The excessive addition of Si significantly improved oxidation resistance of P92 steel, but dramatically impaired the stress-rupture life due to the formation and coarsening of Laves phase. The results indicate that proper additions of Cr, W, and Ce are beneficial for the comprehensive property of P92 steel.

关键词： P92 Oxidation resistance Stress-rupture property Microstructure

CMW-Net: an adaptive robust algorithm for sample selection and label correction

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National Science Review 2023年第6期10卷 19-23页

作者： jun Shu xiang Yuan Deyu Meng School of Mathematics and Statistics Xi'an Jiaotong University Ministry of Education Key Lab of Intelligent Networks and Network Security Xi'an Jiaotong University Peng Cheng Laboratory Pazhou Laboratory (Huangpu)

PROBLEM Deep neural networks (DNNs) have recently achieved impressive performance in various *** successis largely attributed to massive but carefully labeled data expected to properly and sufficiently simulate testing ***,the data collection and annotation processes are often expensiveand time consuming,making obtained training datasets in real-life applications error prone,especially with data biasfrom ideal testing distributions.

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