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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science China(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1.2. sun weiguo1, HOU Shilin3 & {1. hao4 1. {2. of physics, College of Chemical Engineering, sichuan university, Chengdu 61.065, China 2. {2. of Theoretical physics, Xihua Normal university, Nanchong 637002. China 3. Department of physics, China Oceanography university, Qingdao 2.6003, China 4. College of physics, sichuan university, Chengdu 61.065, China 1. institute of {1. College of Chemical Engineering Sichuan University 610065 Chengdu China 2. institute of Theoretical {1. Xihua Normal University 637002 Nanchong China 3. Department of physics China Oceanography University 266003 Qingdao China 4. College of physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Mathematical stencil and its application in finite difference approximation to the Poisson equation

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Science China Mathematics 2005年第10期48卷 1421-1429页

作者： feng Hui~1.ZHANG Baolin~(1.2. & {1. Yang~1.1. Department of Mathematics,Wuhan university,Wuhan 430072.China 2. Laboratory of Computational {2.,institute of Applied {2. and Computational Mathematics,Beijing 1.0088. China 1. Department of Mathematics Wuhan University 430072 Wuhan China 2. Laboratory of Computational physics Institute of Applied Physics and Computational Mathematics 100088 Beijing China

The concept of mathematical stencil and the strategy of stencil elimination for solving the finite difference equation is presented, and then a new type of the iteration algorithm is established for the Poisson equation. The new algorithm has not only the obvious property of parallelism, but also faster convergence rate than that of the classical Jacobi iteration. Numerical experiments show that the time for the new algorithm is less than that of Jacobi and Gauss-Seidel methods to obtain the same precision, and the computational velocity increases obviously when the new iterative method, instead of Jacobi method, is applied to polish operation in multi-grid method, furthermore, the polynomial acceleration method is still applicable to the new iterative method.

关键词： mathematical stencil, stencil elimination, Poisson equation, finite difference, iterative algorithm,parallelism.

Engineering Shewanella-re duce d graphene oxide aerogel biohybrid to efficiently synthesize Au nanoparticles

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Journal of Materials Science & Technology 2024年第1期168卷 50-61页

作者： Baocai Zhang Shulin Shao Huan Yu Qijing {1. Sicheng Shi Qingyuan Wu Zijie Wu Yiyu {2. Yifei Wang Xi sun Deguang Wu {2. Li hao Song Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China College of Biological Engineering Tianjin Agricultural UniversityTianjin 300384China Department of Brewing Engineering Moutai InstituteLuban AveRenhuai 564507China

Biosynthesizing Au nanoparticles(AuNPs)from gold-bearing scraps provides a sustainable method to meet the urgent demand for ***,it remains challenging to efficiently biosynthesize AuNPs of which the diameter is less than 1. nm from a trace amount of Au^(3+)concentration at the level of tens ***,we constructed an exoelectrogenic cell(eCell)-conductive reduced-graphene-oxide aero-gel(rGA)biohybrid by assembling Shewanella sp.S1.SS1.as living biocatalyst and rGA as conductive ad-sorbent,in which Au^(3+)at trace concentrations would be enriched by the adsorption of rGA and reduced to AuNPs through the extracellular electron transfer(EET)of *** regulate the size of the synthe-sized AuNPs to 1. nm,the strain SS1.was engineered to enhance its EET,resulting in strain RS2.pYYD-P tac-ribADEHC&pHG1.-P_(bad)-omcC in SS1..Strain RS2.was further assembled with rGA to construct the RS2.rGA biohybrid,which could synthesize AuNPs with the size of 7.62.2.82.nm from 60 ppm Au^(3+)*** eCell-rGA biohybrid integrated Au^(3+)adsorption and reduction,which enabled AuNPs biosyn-thesis from a trace amount of Au^(3+).Thus,the required Au^(3+)ions concentration was reduced by one or two orders of magnitude compared with conventional methods of AuNPs *** work devel-oped an AuNPs size regulation technology via engineering eCell’s EET with synthetic biology methods,providing a feasible approach to synthesize AuNPs with controllable size from trace level of gold ions.

关键词： Au nanoparticles Exoelectrogenic cell(e-Cell) Shewanella Synthesis biology Extracellular electron transfer Reduced graphene oxide aerogel

Decomposition of pre-existing Au–P clusters induced in situ a-Fe grains uniformization in Fe–P-based nanocrystalline alloys

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Rare Metals 2024年第10期43卷 5242-5255页

作者： Min-hao Han Cheng {1. Guo-Guo Xi Yang Meng Qiang Luo Xue-Qian Yu Wen-{2. Zhang hao liu Hong-Jie Xu Tao Zhang Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang University Laboratory of Functional Fiber Materials Institute of Bast Fiber CropsChinese Academy of Agricultural Science School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast University institute for Advanced Materials North China Electric Power University Center for Advanced Analysis and Computational Science Zhengzhou University

In Fe-based amorphous-/nanocrystalline ribbons,the uniformization and refinement of a-Fe grains are key aspects for optimizing their soft magnetic and mechanical ***,the Fe–P–C–B nanocrystalline alloy system was selected for *** produced as-spun ribbons with pre-existing nanocrystals through melt-quenching and then obtained a well-distributed a-Fe nanocrystalline structure through annealing below the first crystallization onset temperature （633 K）resulting in excellent magnetic properties (saturation magnetization of 1.65 T and coercivity of 1.6 A·m-1.ultra-wide annealing temperature window （from 61. to 733 K）,and extremely high annealing stability （up to 480 min at 633 K）.Furthermore,we propose a new in situ two-step mechanism for the uniformization of a-Fe nanocrystals,which is separately induced by the decomposition of the Au–P clusters and the pre-existing a-Fe nanocrystals during *** work underscores the crucial significance of micro-alloying via metastable clusters primarily influenced by metal-phosphide interactions in the process of refining a-Fe ***,i introduces a new principle for optimizing the comprehensive properties of Fe-based amorphous/nanocrystalline alloys.

关键词： Fe-based nanocrystalline alloys In-situ nano-crystallization Micro-alloying Soft magnetic property

Adjoint method for the optimum planning of industrial pollutant sources

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Science China Earth Sciences 2005年第8期48卷 1270-1279页

作者： liu {1.1.2. HU Fei2.& ZHU Jiang2.1. College of Environmental Sciences, Peking university, Beijing 1.0871. China 2. LAPC, {2. of Atmospheric physics, Chinese Academy of Sciences, Beijing 1.002., China 1. College of Environmental Sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

A study of two-dimensional magnetic polaron

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Science China(physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： liu Tao1. ZHANG Huaihong1. {1. Mang1.2.& WANG Kelin1.3 1. School of Science, Southwest university of Science and Technology, Mianyang 62.1}1., China 2. Wuhan {2. of {12. and Mathematics, Chinese Academy of Sciences, Wuhan 430070, China 3. Department of Modern {12., university of Science and Technology of China, Hefei 2.002., China School of Science Southwest University of Science Technology Mianyang 621010 China Wuhan institute of {1. Mathematics Chinese Academy of Sciences Wuhan 430070 China Department of Modern physics University of Science Technology of China Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern institute of {1. Chengdu 610041People's Republic of China Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1.60 mm to R=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 1.2.nm,and the aberration geometrical radius of the collection optics is tested to be~1.0μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1..The bandwidth of the detector system with the 5×1.^(7)V A^(-1.preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~1. *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

Compression behavior of Zr_(41.Ti_(1.)Cu_(1..5)Ni_(1.)Be_(2..5) bulk metallic glass up to 2. GPa

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Science China(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1. 2., ZHAN Zaiji 2., liu Jing 3 , YUN Jinku 1., {1. Liling 2., liu Riping 1., ZHANG Jun 2.& WANG Wenkui 1. 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan university, Qinhuangdao 066004, China 2. Center for Condensed Matter physics, {2. of physics, Chinese Academy of Sciences, Beijing 1.0080, China 3. BSRF, {2. of High Energy physics, Chinese Academy of Sciences, Beijing 1.0039, China 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41.i1.Cu1..5Ni1.Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Morphologies of Fe-66.7 at.%Si alloy solidified in a drop tube

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Science China(physics,Mechanics & Astronomy) 2005年第6期48卷 658-666页

作者： WANG Haiyan1.2. liu Riping1. MA Mingzhen1. JING Qin1. LI Gong1. {1. Liling2.& WANG Wenkui1.2.1. Key Laboratory of Metastable Materials Science & Technology, Yanshan university, Qinhuangdao 066004, China 2. institute of {12., Chinese Academy of Sciences, Beijing 1.0080, China 1. Key Laboratory of Metastable Materials Science & Technology Yanshan University 066004 Qinhuangdao China 2. institute of {1. Chinese Academy of Sciences 100080 Beijing China

Solidification of 0.1.1.0 mm diameter droplets of Fe-66.7 at.%Si alloy was achieved in a 3 m drop tube. The XRD, EDS, and SEM measurements reveal that all the droplets are composed of the primary phase α and the α+ε eutectic. With decreasing droplet diameter, the growth mode of the primary phase α changes from faceted to nonfaceted growth and the eutectic changes from needle-like to anomalous eutectic. In addition, the width of the primary phase α decreases with decreasing droplet size. The different cooling rates and undercooling levels corresponding to the samples with different sizes are responsible for the morphology changes. The cooling rates of the samples with different diameters during free fall were calculated and their effects on the microstructure formation were discussed. This kind of transition is also found inside the same sample, which is due to the larger cooling rate on the surface than at the center.

关键词： Fe-Si alloy, solidification, drop tube, undercooling.