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New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2. YANG Feng3. XIAO Hui1, RAO Li-min1 (1. school of {2. engineering and Technology, East{3. Institute of Technology, Fuzhou 3.4000, Jiangxi,{3. 2. school of Mechanical engineering and Automation, Northeastern university, Shenyang 110004, Liaoning,{3. 3. school of Civil and Environmental engineering, East{3. Institute of Technology, Fuzhou 3.4000, Jiangxi,{3.) school of nuclear {2. and Technology East China Institute of Technology Fuzhou Jiangxi China school of Mechanical engineering and Automation Northeastern University Shenyang Liaoning China school of Civil and Environmental engineering East China Institute of Technology Fuzhou Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

Magnetic moments of ^(3.)Mg in the time-odd relativistic mean field approach

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1586-1592页

作者： LI Jian1,ZHANG Ying1,YAO JiangMing1 & MENG Jie1,2.1 school of Physics,State Key Laboratory of nuclear Physics and Technology,Peking {2.,Beijing 100871,{3. 2.school of Physics and nuclear Energy engineering,beihang {2.,Beijing 100191,{3. school of Physics State Key Laboratory of Nuclear Physics and Technology Peking University Beijing China school of Physics and nuclear Energy {2. Beihang University Beijing China

The configuration-fixed deformation constrained relativistic mean field approach with time-odd component has been applied to investigate the ground state properties of 3.Mg with effective interaction *** ground state of 3.Mg has been found to be prolate deformed,β2.0.2.0}with the odd neutron in 1/2.3.0] orbital and the energy -2.1.85 MeV which is close to the data -2.2.06 *** magnetic moment -0.913. μN is obtained with the effective electromagnetic current which well reproduces the data -0.7456 μN self-consistently without introducing any *** energy splittings of time reversal conjugate states,the neutron current,the energy contribution from the nuclear magnetic potential,and the effect of core polarization are discussed in detail.

关键词： magnetic moment binding energy time-odd component configuration-fixed deformation constrained calculation relativistic mean field theory

Optimization of the imaginary time step evolution for the Dirac equation

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Science china(Physics,Mechanics & Astronomy) 2011年第2期54卷 231-235页

作者： LI FangQiong1,ZHANG Ying2.LIANG HaoZhao2.3.& MENG Jie4,2.5 1Guizhou university for Nationalities,Guiyang 55002.,{2. 2.tate Key Lab nuclear Physics & Technology,{3. of Physics,Peking university,Beijing 100871,{2. 3.nstitut de Physique Nucle’aire,IN2.3.CNRS and Universite’ Paris-Sud,F-91406 Orsay Cedex,France 4{3. of Physics and nuclear Energy engineering,{12. university,Beijing 100191,{2. 5Department of Physics,university of Stellenbosch,Stellenbosch,South Africa Guizhou university for Nationalities Guiyang China State Key Lab nuclear Physics & Technology School of Physics Peking University Beijing China Institut de Physique Nucléaire IN2P3-CNRS and Université Paris-Sud Orsay Cedex France school of Physics and nuclear Energy {2. Beihang University Beijing China Department of Physics University of Stellenbosch Stellenbosch South Africa

Taking the single neutron levels of 12. in the Fermi sea as examples,the optimization of the imaginary time step(ITS) evolution with the box size and mesh size for the Dirac equation is *** the weakly bound states,in order to reproduce the exact single-particle energies and wave functions,a relatively large box size is *** long as the exact results can be reproduced,the ITS evolution with a smaller box size converges faster,while for both the weakly and deeply bound states,the ITS evolutions are less sensitive to the mesh ***,one can find a parabola relationship between the mesh size and the corresponding critical time step,i.e.,the largest time step to guarantee the convergence,which suggests that the ITS evolution with a larger mesh size allows larger critical time step,and thus can converge faster to the exact *** conclusions are very helpful for optimizing the evolution procedure in the future self-consistent calculations.

关键词： Dirac equation Schrdinger-like equation imaginary time step method convergence

Convergence for Imaginary Time Step evolution in the Fermi and Dirac seas

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 327-330页

作者： LI FangQiong1,ZHANG Ying2.& MENG Jie2.3.4 1Guizhou university for Nationalities,Guiyang 55002.,{2. 2.tate Key Lab Nucl. Phys. & Tech.,school of Physics,Peking university,Beijing 100871,{2. 3.2. of Physics and nuclear Energy engineering,beihang university,Beijing 100191,{2. 4Department of Physics,university of Stellenbosch,Stellenbosch,South Africa Guizhou university for Nationalities Guiyang China State Key Lab Nucl. Phys. & Tech. School of Physics Peking University Beijing China school of Physics and nuclear Energy {2. Beihang University Beijing China Department of Physics University of Stellenbosch Stellenbosch South Africa

The convergence for the Imaginary Time Step (ITS) evolution with time step is investigated by performing the ITS evolution for the Schrdinger-like equation and the charge-conjugate Schrdinger-like equation deduced from Dirac equation for the single proton levels of 12. in both the Fermi and Dirac seas. For the guaranteed convergence of the ITS evolution to the "exact" results,the time step should be smaller than a "critical" time step Δtc for a given single-particle level. The "critical" time step Δtc is more sensitive to the quantum numbers |κ| than to the energy of the single-particle level. For the single-particle levels with the same κ,their "critical" time steps are in the same order. For the single-particle levels with similar energy,a relatively small (large) "critical" time step for larger (smaller) |κ| is needed. These conclusions can be used in the future self-consistent calculation to optimize the evolution procedure.

关键词： Dirac equation Schrdinger-like equation Imaginary Time Step method convergence

Exotic structure of the third excited state in^(2.)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3. LIANG Yujie1,2.3. DENG Fuguo1,2.3. LIU Zuhua1,4 & ZHOU Hongyu1,2.3.1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, Beijing Normal university, Beijing 100875, china 2. Institute of Low Energy nuclear Physics, and Department of Material Science and {3., Beijing Normal university, Beijing 100875, china 3. Beijing Radiation Center, Beijing 100875, china 4. china Institute of Atomic Energy, Beijing 102.13. china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy nuclear Physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

β-delayed proton decays near the proton drip line

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000,{2. 2. nuclear Physics Department,{2. Institute of Atomic Energy, Beijing 102.13.{2. 3. Department of Technical Physics, Peking university, Beijing 100871,{2. 4. Shanghai Institute for nuclear Research, Shanghai 2.1800,{2. Institute of Modern Physics Chinese Academy of Sciences Lanzhou China nuclear Physics Department China Institute of Atomic Energy Beijing China Department of Technical Physics Peking University Beijing China Shanghai Institute for nuclear Research Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142.o and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Parameter estimation for whole-body kinetic model of FDG metabolism

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Progress in Natural Science:Materials International 2006年第11期16卷 1164-1170页

作者： CUI Yunfeng~1, BAI Jing~1**, CHEN Yingmao~2.and TIAN Jiahe~2.1. Department of Biomedical engineering, Tsinghua university, Beijing 100084,{2. 2. Department of {3. Medicine, General Hospital of PLA, Beijing 100853.{2.) Department of Biomedical engineering Tsinghua University Beijing 100084 China Department of nuclear Medicine General Hospital of PLA Beijing 100853 China

Based on the radioactive tracer [ ~ 18 F]2.fluoro-2.deoxy-D-glucose （FDG）, positron emission tomography （PET）, and compartment model, the tracer kinetic study has become an important method to investigate the glucose metabolic kinetics in human body. In this work, the kinetic parameters of three-compartment and four-parameter model for the FDG metabolism in the tissues of myocardium, lung, liver, stomach, spleen, pancreas, and marrow were estimated through some dynamic FDG-PET experiments. Together with published brain and skeletal muscle parameters, a relatively complete whole-body model was presented. In the liver model, the dual blood supply from the hepatic artery and the portal vein to the liver was considered for parameter estimation, and the more accurate results were obtained using the dual-input rather than the single arterial-input. The established whole-body model provides the functional information of FDG metabolism in human body. It can be used to further investigate the glucose metabolism, and also be used for the simulation and visualization of FDG metabolic process in human body.

关键词： compartment model FDG PET parameter estimation.

Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 487-495页

作者： ZHAO Weijuan1, LU Xiaoke1, LI Guoxia1, GUO Min1, XIE Jianzhong1, GAO Zhengyao1, SUN Xinmin2. GUO Musen2. CHENG Huansheng3.& ZHANG Bin3.1. Faculty of Physical {2., Zhengzhou university, Zhengzhou 450052. china 2. Research Institute of Cultural Relic and Archaeology, Henan Province, Zhengzhou 450004, china 3. Research Institute of Modern Physics, Fudan university, Shanghai 2.043., china Faculty of Physical engineering Zhengzhou University Zhengzhou China Research Institute of Cultural Relic and Archaeology Zhengzhou China Research Institute of Modern Physics Fudan University Shanghai China

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

关键词： Zhanggongxiang kiln, Qingliangsi kiln, the source of raw material, the proton induced X-ray emission.

Selected issues at the interface between nuclear physics and astrophysics as well as the standard model

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 119-123页

作者： MENG Jie1,2.3. NIU ZhongMing1, LIANG HaoZhao1 & SUN BaoHua2.4 1State Key Laboratory of nuclear Physics and Technology, {2. of Physics, Peking university, Beijing 100871,{3. 2.2. of Physics and nuclear Energy engineering, beihang university, Beijing 100191,{3. 3.epartment of Physics, university of Stellenbosch, Stellenbosch, South Africa 4Justus-Liebig-Universita¨t Giessen, Heinrich-Buff-Ring 14, Giessen 3.3.2. Germany State Key Laboratory of nuclear Physics and Technology School of Physics Peking University Beijing China school of Physics and nuclear Energy {2. Beihang University Beijing China Department of Physics University of Stellenbosch Stellenbosch South Africa Justus-Liebig-Universität Giessen Giessen Germany

The density functional theory (DFT) with a minimal number of parameters allows a very successful phenomenological description of ground state properties of nuclei all over the periodic table. The recent developments on the application of the covariant density functional theory as well as its extensions by the group in Beijing for a series of interests and hot topics in nuclear astrophysics and nuclear structure are reviewed, including the rapid neutron-capture process, Th/U chronometer, and isospin corrections for superallowed β transitions.

关键词： rapid neutron-capture process nuclear chronometer isospin symmetry-breaking corrections