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Scaling limit theorem for transient random walk in random environment

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Frontiers of mathematics in china 2018年第5期13卷 1033-1044页

作者： wenming hong Hui YANG School of Mathematical Sciences & Laboratory of mathematics and Complex Systems Beijing Normal University Beijing 100875 China College of Science Minzu University of China Beijing 100081 China

We construct a sequence of transient random walks in random environments and prove that by proper scaling, it converges to a diffusion process with drifted Brownian potential. To this end, we prove a counterpart of co... 详细信息

关键词： Random walk random environment diffusion process Brownian motion with drift

Programmable repulsive potential for tight-binding from Chen-Möbius inversion theorem

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Science china(Physics,Mechanics & Astronomy) 2024年第1期67卷 71-83页

作者： Jian-Gao Li Jin-Kun Tang hong-Quan Song Gotthard Seifert Dong-Bo Zhang College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China department of Physics Beijing Normal UniversityBeijing 100875China College of Physics and Telecommunication Engineering Zhoukou Normal UniversityZhoukou 466001China Theoretische Chemie Technische Universität DresdenDresden D-01062Germany

An accurate total energy calculation is essential in materials *** date,many tight-binding(TB)approaches based on parameterized hopping can produce electronic structures comparable to those obtained using first-principles ***,TB approaches still have limited applicability for determining material properties derived from the total *** is,the predictive power of the TB total energy is impaired by an inaccurate evaluation of the repulsive *** complexity associated with the parametrization of TB repulsive potentials is the weak link in this *** this study,we propose a new method for obtaining the pairwise TB repulsive potential for crystalline materials by employing the Chen-Möbius inversion *** show that the TB-based phonon dispersions,calculated using the resulting repulsive potential,compare well with those obtained by first-principles calculations for various systems,including covalent and ionic bulk materials and twodimensional *** present approach only requires the first-principles total energy and TB electronic band energy as input and does not involve any *** striking feature enables us to generate repulsive potentials programmatically.

关键词： tight binding first-principles calculation total energy repulsive potential phonon dispersion

Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and Macroelement Concentrations in Pak-choi (Brassica chinensis L.)

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Pedosphere 2007年第5期17卷 595-600页

作者： WANG Hua-Jing WU Liang-Huan WANG Min-Yan ZHU Yuan-hong TAO Qin-Nan ZHANG Fu-Suo Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 （China） College of Geography and Resource Sciences Sichuan Normal University Chengdu 610066 （China） department of Crop and Soil Sciences the Pennsylvania State University （USA） College of Resources and Environment China Agricultural University Beijing 100094 （China）

A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen （N）, phosphorus （P）, and potassium （K） in pak-choi （Brassica chinensis L.） shoots. When 20% of nitrate-N was replaced with arginine （Arg） compared to the full nitrate treatment, pak-choi shoot fresh and dry weights increased significantly （P ≤ 0.05）, but when 20% of nitrate-N was replaced with alanine （Ala）, valine （Val）, leucine （Leu）, isoleucine （Ile）, proline （Pro）, phenylalanine （Phe）, methionine （Met）, aspartic acid （Asp）, glutamic acid （Glu）, lysine （Lys）, glycine （Gly）, serine （Ser）, threonine （Thr）, cysteine （Cys）, and tyrosine （Tyr）, shoot fresh and dry weights decreased significantly （P ≤ 0.05）. After replacing 20% of nitrate-N with asparagine （Asn） and glutamine （Gin）, shoot fresh and dry weights were unaffected. Compared to the full nitrate treatment, amino acid replacement treatments, except for Cys, Gly, histidine （His）, and Arg, significantly reduced （P ≤0.05） nitrate concentrations in plant shoots. Except for Cys, Leu, Pro, and Met, total N concentrations in plant tissues of the other amino acid treatments significantly increased （P ≤ 0.05）. Amino acids also affected total P and K concentrations, but the effects differed depending on individual amino acids. To improve pak-choi shoot quality, Gln and Asn, due to their insignificant effects on pak-choi growth, their significant reduction in nitrate concentrations, and their increase in macroelement content in plants, may be used to partially replace nitrate-N.

关键词： amino acids growth N P and K nitrate accumulation pak-choi

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紫草素的电化学研究

分析测试学报 2001年第5期20卷 50-52页

作者：袁倬斌邹洪中国科学技术大学研究生院化学系北京100039 首都师范大学化学系北京100037

建立了测定紫草素的单扫描极谱分析方法 ;在0.03mol/LNa2CO3+0.2mol/LNaOH(pH=12.63)底液中 ,紫草素于 -0.60V(SCE)处有一灵敏的二次导数还原峰 ,电流峰高与浓度在7.0×10 -8～5.6×10 -7mol/L和6.0×10-7～4.2×10-5 mol/L范围内呈线... 详细信息

建立了测定紫草素的单扫描极谱分析方法 ;在0.03mol/LNa2CO3+0.2mol/LNaOH(pH=12.63)底液中 ,紫草素于 -0.60V(SCE)处有一灵敏的二次导数还原峰 ,电流峰高与浓度在7.0×10 -8～5.6×10 -7mol/L和6.0×10-7～4.2×10-5 mol/L范围内呈线性关系,检出限为3.5×10-8mol/L;用于中药紫草中紫草素的测定 ,结果良好 ;同时还研究了紫草素的电极反应机理。

关键词：紫草素单扫示波极谱法中药紫草分析电化学

BAC-PROCESS IN BIOLOGICAL POWDERED ACTIVATED CARBON-MICROFILTRATION FOR TREATING MICRO-POLLUTED WATER SOURCE

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BAC-PROCESS IN BIOLOGICAL POWDERED ACTIVATED CARBON-MICROFIL...

Extremum of a time-inhomogeneous branching random walk

第4届流域管理和城市供水国际会议

作者： LIU hong~(1*) HE Yun-hua~2 Quan Xiang-chun~3 Zhang guang-ming~4 LI An-jie~3 (1.department of Environmental Engineering,beijing university of Aeronautics and Astronautics,beijing,100083,china 2.Office of South-to-North Water Diversion Project Committee of State Council,beijing,100053 3.School of Environmental,beijing normal university,beijing,100875,china 4.Shenzhen Graduate School,Tsinghua university,Xili Univ.Town,Shenzhen,518055,china)

The performance of BPAC-M F system and the process of biological activated carbon(BAC)were studied fortreating micro-polluted water *** wastewater was from Guanting Reservoir in beijing,and HRT(HydraulicResidual Time)of the system was set at *** results showed that the BPAC-MF system could start up quickly by theadsorption of BPAC before biofilm was established in the *** the adsorption capacity of PAC declined,the biofilmestablished in the system could take an important role in removing *** combined function of microorganisms andPAC(Powdered Activated Carbon)made the system maintain a high removal of organic *** average removalefficiency of organic matters characterized with COD,UVand UVfor the system was 68.42%,75.61% and 87.50%,respectively,at the temperature lower than 10°*** system demonstrated strong advantages to operate at low *** measurement of AOC showed that the removal efficiency of AOC(Assimilable Organic Carbon)was 60.22% and theeffluent water could meet the desired criterion of 100 ug acetate-C/L for biologically stable *** mechanism ofBPAC-MF system was investigated through measuring he apparent molecular size distribution(AMSD)of *** performance of BPAC-MF system depended on the joint functions of BPAC biodegradation and *** addition,the biodegradation kinetics of BPAC was also studied.

关键词： Water treatment Micro-polluted water source Biological Activated Carbon Microfiltration

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Frontiers of mathematics in china 2021年第2期16卷 459-478页

作者： Wanting HOU Xiaoyue ZHANG wenming hong department of mathematics Northeastern UniversityShenyang 110004China School of Statistics Capital University of Economics and BusinessBeijing 100070China School of Mathematical Sciences&Laboratory of mathematics and Complex Systems Beijing Normal UniversityBeijing 100875China

Consider a time-inhomogeneous branching random walk, generated by the point process Ln which composed by two independent parts: ‘branching’offspring Xn with the mean 1+B(1+n)−β for β∈(0,1) and ‘displacement’ ξn with a drift A(1+n)^(−2α) for α∈(0,1/2), where the ‘branching’ process is supercritical for B>0 but ‘asymptotically critical’ and the drift of the ‘displacement’ ξn is strictly positive or negative for |A|>0 but ‘asymptotically’ goes to zero as time goes to infinity. We find that the limit behavior of the minimal (or maximal) position of the branching random walk is sensitive to the ‘asymptotical’ parameter β and α.

关键词： Branching random walk time-inhomogeneous branching process random walk

Survey on Pre-service Teacher Educational Technology Literacy Status Take the Jiangxi normal university as the example

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Survey on Pre-service Teacher Educational Technology Literac...

Illuminating dark sirens with CSST

2010 International Conference on Intelligent Computing and Cognitive Informatics (ICICCI 2010)

作者： Jing Liu Hailong Men Jun Han Xiaodan Zhao department of Educational Technology Capital normal university beijing 100048 china

Along with information technology’s fast development,the educational technique receives the attention in ***,in the current international education form modernization,under the integrated environment,before the exploration,studies and promotes our country current duty,the teacher educational technique accomplishment level to educate the system sustainable healthy development in our country in the advancement to have the direct reality *** the research method of questionnaire survey and case interview,this article takes 200 pre-service teachers of Jiangxi normal university as object,and make survey on their educational technology literacy,including educational technique manner and consciousness,the theoretical knowledge and the skill level,carries on the teaching system designed capacity using the educational technique as well as "the educational technique" the public election class teacher’s teaching situation carries on the *** this article proposes the state and the reason and problems behind the *** makes every effort to provide the objective material basis for our country’s educational technique accomplishment level enhancement.

关键词： Pre-service teachers Educational Technology L iteracy Survey

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Science china(Physics,Mechanics & Astronomy) 2024年第3期67卷 165-165页

作者： Zong-hong Zhu School of Physics and Technology Wuhan UniversityWuhan 430072China department of Astronomy Beijing Normal UniversityBeijing 100875China

In recent years, the Hubble tension has emerged as one of the most perplexing enigmas within the realm of cosmology[1]. This incongruity suggests the tantalizing prospect of new physics beyond the standard ΛCDM model, leading to the proposal of diverse extended cosmological models. At the same time, there is a pressing demand for novel cosmological tools to mediate the Hubble tension. The gravitational-wave(GW) standard siren has been put forth as a promising cosmological probe for resolving the Hubble tension, provided that the redshift of the GW source is known, as exemplified in ref. [2].

关键词： gravitational source beyond

MECHANICAL MODELING OF THE BISTABLE BACTERIAL FLAGELLAR FILAMENT

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Acta Mechanica Solida Sinica 2011年第S1期24卷 1-16页

作者： Xiaoling Wang 1 Qingping Sun 2 1 ( 1 School of Mechanical Engineering, university of Science & Technology beijing, beijing 100083, china) ( 2 department of Mechanical Engineering, The hong Kong university of Science & Technology, Clear Water Bay, Kowloon, hong Kong, china)

We extend the 2D Landau phase transition theory to the bacterial flagellar filament which displays the phase transition between the left handed normal form and the right handed semi-coiled form. The bacterial flagellar filament is treated as an elastic thin rod based on the Kirchhoff’s thin rod theory. Mechanical analysis is performed on the periodical phase transition of the filament between the two helical structures of the opposite charity. The curvature and twist are chosen as the order parameters in constructing the phase transition model of the filament. The established model is applied to study the instability properties of the filament and to investigate the loading and deformation conditions of the phase transition. In addition, the curvature and twist gradient energy are considered to describe the interface properties of the two phases.

关键词： bacterial flagellar filament Landau theory the Kirchhoff’s rod theory instability