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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 550025,china 2state key lab nucl.ar physics & tech.ology,school of physics,peking university,beijing 100871,china 3Institut de phys.que nucl.’aire,IN2P3-CNRS and Universite’ Paris-Sud,F-91406 Orsay Cedex,France 4school of physics and nucl.ar Energy Engineering,Beihang university,beijing 100191,china 5Department of physics,university of Stellenbosch,Stellenbosch,South Africa 1. Guizhou university for Nationalities Guiyang 550025 China2. State Key Lab Nuclear Physics & Technology School of Physics Peking University Beijing 100871 China3. Institut de Physique Nucléaire IN2P3-CNRS and Université Paris-Sud F-91406 Orsay Cedex France4. School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China5. Department of Physics University of Stellenbosch Stellenbosch South Africa

Taking the single neutron levels of 12C 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

Design of a new dynamical core for global atmospheric models based on some efficient numerical methods

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Science china Mathematics 2004年第z1期47卷 4-21页

作者： WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU Hongtaostate key laboratory of Numerical Modeling for Atmospheric Sciences and Geophys.cal Fluid Dynamics, Institute of Atmospheric physics, Chinese Academy of Sciences, beijing 100029, china Department of Computational Mathematics, Academy of Mathematics and System Sciences, peking university, beijing 100871, china Chinese Acad Sci Inst Atmospher Phys State Key Lab Numer Modeling Atmospher Sci & Geop Beijing 100029 Peoples R China peking Univ Acad Math & Syst Sci Dept Computat Math Beijing 100871 Peoples R China

A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the phys.cal packagesfrom the Community Atmospheric Model Version 2 (CAM2) of NationalCenter for Atmospheric Research (NCAR), are included.

关键词： dynamical core, equal-area mesh, anti-symmetry, effective energy conservation.

Chiral doublet bands in odd-A nucl.i 103,105Rh

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Chiral doublet bands in odd-A nuclei 103,105Rh

EFFECT OF MOLECULAR WEIGHT OF PEO ON THE STRUCTURE AND PROPERTIES OF PDMAEMA/PEO HYDROGELS

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Bin Qi~(1 1)) Shou Yu Wang~1 Shuang Quan Zhang~2 Jie Meng~2 1(school of Space Science and physics,Shandong university at Weihai,Weihai 264209,china) 2(school of physics,and state-key lab.nucl.phys.& tech.,peking university,beijing 100871,china)

Spontaneous chiral symmetry breaking is a phenomenon of general interest in chemistry,biology and particle *** the pioneering work of nucl.ar chirality in 1997,much effort has been devoted to further explore this interesting *** the observation of chiral doublet bands in N = 75 isotones, more candidates have been reported over more than 20 nucl.i experimentally in A～100,130 and 190 mass regions including odd-odd,odd-A and even-even nucl.i.

关键词： nucl.ar chirality odd-A nucl.i many-particle many-hole configuration particle rotor model

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Chinese Journal of Polymer Science 2006年第1期24卷 35-40页

作者： Zhu-gen Liu Min Yi Mao-lin Zhai and Hong-fei Ha Department of Applied Chemistry and The key laboratory of Polymer Chemistry and physics of Ministry of Education,College of Chemistry & Molecular Engineering,peking university,beijing 100871,china peking Univ Coll Chem & Mol Engn Dept Appl Chem Beijing 100871 Peoples R China peking Univ Coll Chem & Mol Engn Minist Educ Key Lab Polymer Chem & Phys Beijing 100871 Peoples R China

A new kind of binary hydrogels composed of poly（dimethylaminoethylmethacrylate）（PDMAEMA） and poly（ethylene oxide）（PEO） with varying weight average molecular weights （M^-w = 5 × 10^4, 1 × 10^5 and 2.5 × 10^6） were prepared by У-irradiation tech.ology. The properties of PDMAEMA/PEO hydrogels obtained were evaluated in terms of gel fraction, gel strength, thermal characterization and swelling behavior. The gel strength and swelling degree of the hydrogels could be improved obviously after adding PEO into the PDMAEMA system, while the degree of improvement decreased with increasing M^-w of PEO. The temperature sensitivity of PDMAEMA/PEO was retained only in the sample with PEO of M^-w = 5 × 10^4, and the pH sensitivity was retained in samples with PEO of M^-w = 5 × 10^4 and 1 × 10^5. When DMAEMA/PEO mixtures containing PEO of M^-w = 5 × 10^4 were irradiated, the main reaction could be the cross-linking of DMAEMA, and the linear PEO molecular chains could penetrate into the cross-linked network of PDMAEMA. With increasing M^-w of PEO, some side reactions were induced, such as grafting of DMAEMA onto PEO molecules, the scission or cross-linking of PEO.

关键词： Poly(dimethylaminoethylmethacrylate) Poly(ethylene oxide) Molecular weight Binary hydrogels Irradiation.

FABRICATION OF SELF-ASSEMBLY DNA-C_(60) MULTILAYER FILMS

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Chinese Journal of Polymer Science 2002年第6期20卷 591-593页

作者： Shu-guang Yang Yong-jun Zhang Xin-hua Dai Wen-hong Tang Chun-yan Liu Wei-xiao Cao Yu-liang Li Jian Xu state key laboratory of Polymer physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences,beijing 100080, china tech.ology Institute of physics and Chemistry Chinese Academy of Sciences, beijing 100101, china College of Chemistry and Molecular Engineering peking university beijing 100871, china Chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China Chinese Acad Sci Technol Inst Phys & Chem Beijing 100101 Peoples R China peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China

Electrostatic layer-by-layer self-assembly multilayer films were successfully fabricated from C-60-ethylenediamine adduct (C-60-EDA) and DNA. Under visible light irradiation, DNA is ready to be cleaved and the films a... 详细信息

关键词： self-assembly photo-induced cleavage DNA C-60

FORMATION OF MESOPHASE MONO-DOMAINS AND MICRO-STRUCTURES IN THIN FILMS OF A SERIES OF COPOLYETHERS CONTAINING BOTH ODD-NUMBERED METHYLENE UNITS

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Chinese Journal of Polymer Science 2001年第4期19卷 391-397页

作者： Feng-chao Xie Jie-ping Liu Dong-hang Yan Tian-bai He Ru-qing Zheng Er-qiang Chen state key laboratory of Polymer physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, china Department of Polymer Science and Engineering College of Chemistry peking university beijing 100871, china Chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The structural and morphological evolution of mono-domains in thin films has been investigated for a series of liquid crystalline (LC) copolyethers. The copolyethers studied were synthesized by the reaction of 1-(4-hydroxy-4 ' -biphenylyl)-2-(4-hydroxyl-phenyl)propane (TPP) with 1,7-dibromoheptane and 1,11-undecane at different compositions (coTPPs-7/11). In contrast to the solution-cast thin films without annealing, which exhibit the isotropic homogeneous molecular orientation, mono-domains with a homeotropic alignment were found in coTPP-7/11(5/5) after the thin films were annealed in the high-temperature columnar phase (Phi '). Similar to the nucl.ation process in polymer crystallization, transmission electron microscopic observations show that small mono-domains appear in the initial stage of annealing, where molecules form a uniaxial in-plane chain orientation. With increasing annealing time, the molecular orientation gradually became tilted with respect to the substrate surface, and finally, a uniaxial homeotropic molecular orientation was achieved after a prolonged annealing time. The lateral size of mono-domains was found to increase continuously with annealing time and grew into a circular shape, indicating an isotropic lateral growth scheme which implies a hexagonal molecular packing proved by the electron diffraction experiments.

关键词： main-chain liquid crystalline polymer structure morphology

Level structure of 116Sb

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Level structure of 116Sb

High spin structures in A～110 mass region

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： D.P.Sun,~(1 1)) S.Y.Wang,~1 B.Qi,~1 L.W.Duan,~1 G.Wang,~1 X.L.Ren,~1 B.T.Duan,~1 X.X.Zhu,~1 F.Z.Lv,~1 C.Liu,~1 C.J.Xu,~1 H.Hua,~2 S.Q.Zhang,~2 Z.Y.Li,~2 J.M.Yao,~2 L.H.Zhu~3 X.G.Wu,~3 G.S.Li,~3 Y.Liu,~3 X.Q.Li,~3 Y.Zheng,~3 L.L.Wang,~3 L.Wang,~3 1(school of Space Science and physics,Shandong university at Weihai,Weihai 264209,china) 2(school of physics,and state-key lab.nucl.phys.& tech.,peking university,beijing 100871,china) 3(china Institute of Atomic Energy,beijing 102413,china)

The odd-odd nucl.us Sb was populated using the reaction Cd（Li,5n） at a beam energy of 48 *** previously known rotational bands have been observed up to high spins.A new△I = 1 band were identified,and were suggested as a magnetic rotational *** rotor model calculations show reasonably good agreement with the *** the spherical discrete levels were also *** 30 newγ—rays were added in the level scheme of Sb.

关键词： odd-odd nucl.us magnetic rotational band level scheme

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High spin structures in A～110 mass region