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The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, wang Dehua2. DU Mengli3 & LIN Shenglu1 1. College of Physics and Electronics, Shandong normal {2., Jinan 2.0014, china 2. department of mathematics and Physics, Shandong Institute of Architecture and Engineering, Jinan 2.0014, china 3. Institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100080, china 1. College of Physics and Electronics Shandong Normal University 250014 Jinan China 2. department of mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 2.. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

The refined theory of deep rectangular beams for symmetrical deformation

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 919-925页

作者： GAO Yang1 & wang MinZhong2.1 College of Science, china Agricultural {2., beijing 100083, china 2.State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace Engineering, Peking {2., beijing 100871, china College of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace Engineering Peking University Beijing 100871 China

Based on elasticity theory, various one-dimensional equations for symmetrical deformation have been deduced systematically and directly from the two-dimensional theory of deep rectangular beams by using the Papkovich-Neuber solution and the Lur'e method without ad hoc assumptions, and they construct the refined theory of beams for symmetrical deformation. It is shown that the displacements and stresses of the beam can be represented by the transverse normal strain and displacement of the mid-plane. In the case of homogeneous boundary conditions, the exact solutions for the beam are derived, and the exact equations consist of two governing differential equations: the second-order equation and the transcendental equation. In the case of non-homogeneous boundary conditions, the approximate governing differential equations and solutions for the beam under normal loadings only and shear loadings only are derived directly from the refined beam theory, respectively, and the correctness of the stress assumptions in classic extension or compression problems is revised. Meanwhile, as an example, explicit expressions of analytical solutions are obtained for beams subjected to an exponentially distributed load along the length of beams.

关键词： deep rectangular beams the refined theory symmetrical deformation the Papkovich-Neuber solution the Lur’e method

Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science china Earth Sciences 2010年第5期53卷 721-730页

作者： wang DongWei1,2.3, wang JinDi1,2.& LIANG ShunLin4 1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by{2. and Institute of Remote Sensing Applications, CAS, beijing 100875, china 2.School of Geography, beijing Key Laboratory of Environmental Remote Sensing and Digital City,{2., beijing 100875, china 3 Haihe River Water Conservancy Commission, Tianjin 300170, china 4 department of Geography, university of Maryland, College Park, MD 2.742. USA 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing 100875 China2. School of Geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing 100875 China3. Haihe River Water Conservancy Commission Tianjin 300170 China4. Department of Geography University of Maryland College Park MD 20742 USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of beijing, this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

A Theoretical Study on Nonadiabatic Trapping Models of the Reaction NH+H←→N+H_2

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Chinese Chemical Letters 1999年第3期10卷 207-208页

作者： Shu Xia YIN Yan wang WenLin FENG(department of Chemistry,{2. normal university,{2. 100873) beijing normal Univ Dept Chem Beijing 100875 Peoples R China

The properties of nonadiabatic trapping models of the reaction NH+H -N+H, are investigated in a collinear model as \veil as a non-collinear thermal reaction on the basis of theintrinsic reaction coordinate (IRC) intbrmation obtained by ah initio calculations at QCISD/631 IG** ie\el. Using the unitied statistical theory fornonadiabatic trapping models. the thermal rateconstants over the temperature range of 2.00-3000K are computed which are in excellent agreementwith the experiment results.

关键词： Intrinsic reaction coordinate (IRC) unified statistical theory (UST) nonadiabatic trapping model thermal rate constant

The formation and stability of Si_(1-x)C_x alloys in Si implanted with carbon ions

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Chinese Science Bulletin 2001年第3期46卷 200-204页

作者： wang Yinshu, LI Jinmin, JIN Yunfan, wang Yutian, SUN Guosheng & LIN Lanying1. {2. of Physics, beijing normal university, beijing 100875, china 2. Institute of Semiconductors, Chinese Academy of Sciences, beijing 100083, china 3. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, china department of Physics Beijing Normal University Beijing China Institute of Semiconductors Chinese Academy of Sciences Beijing China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China

Si1-xCx alloys of carbon (C) concentration between 0.6%-1.0% were grown in Si by ion implantation and high temperature annealing. The formation of Si1-xCx alloys under different ion doses and their stability during annealing were studied. If the implanted dose was less than that for amorphizing Si crystals, the implanted C atoms would like to combine with defects produced during implantation and it was difficult to form Si1-xCx alloys after being annealed at 850℃. With the increment of implanted C ion doses, the lattice damage increased and it was easier to form Si1-xCx alloys. But the lattice strain would become saturate and only part of implanted carbon atoms would occupy the substitutional positions to form Si1-xCx alloys as the implanted carbon dose increased to a certain degree. Once Si1-xCx alloys were formed, they were stable at 950℃, but part of their strain would release as the annealing temperature increased to 1 000℃. Stability of the alloys became worse with the increment of carbon

关键词： ion implantation Si1-xCx alloys stability of Si1-xCx alloys.

The Influence of Minimal Subgroups on the Structure of Finite Groups

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Acta Mathematica Sinica,English Series 2000年第1期16卷 63-70页

作者： Yanming wang mathematics {2.,Zhongshan university,Guangzhou 5102.5,P.R.china mathematics department Zhongshan University Guangzhou 510275 P.R. China

Let G be a finite *** question how the properties of its minimal subgroups influence the structure of G is of considerable interest for some *** this paper we try to use c-normal condition on minimal subgroups to char... 详细信息

关键词： c-normal subgroup Supersolvable Nilpotent Generalized Fitting subgroup

Bioorthogonal microglia-inspired mesenchymal stem cell bioengineering system creates livable niches for enhancing ischemic stroke recovery via the hormesis

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1412-1427页

作者： Jianpei Xu Yinzhe Sun Yang You Yuwen Zhang Dan Huang Songlei Zhou Yipu Liu shiqiang Tong Fenfen Ma Qingxiang Song Chengxiang Dai Suke Li Jigang Lei Zhihua wang Xiaoling Gao Jun Chen Shanghai Pudong Hospital&department of Pharmaceutics School of PharmacyFudan UniversityShanghai 201203China Key Laboratory of Smart Drug Delivery Ministry of EducationSchool of PharmacyFudan UniversityShanghai 201203China department of Pharmacology and Chemical Biology State Key Laboratory of Oncogenes and Related GenesShanghai Universities Collaborative Innovation Center for Translational MedicineShanghai Jiao Tong University School of MedicineShanghai 200025China department of Emergency Shanghai Pudong HospitalFudan University Pudong Medical CenterShanghai 201399China Institute of Science and Technology for Brain-Inspired Intelligence&department of Neurology Fudan UniversityShanghai 201203China department of Rehabilitation Medicine Huashan HospitalFudan UniversityShanghai 201203China Daxing Research Institute University of Science and Technology BeijingBiomedical Industry BaseZhongguancun Science and Technology ParkBeijing 102600China Cellular Biomedicine Group Inc. Shanghai 201210China

Mesenchymal stem cells(MSCs)experience substantial viability issues in the stroke infarct region,limiting their therapeutic efficacy and clinical *** levels of deadly reactive oxygen radicals(ROS)and proinflammatory cytokines(PC)in the infarct milieu kill transplanted MSCs,whereas low levels of beneficial ROS and PC stimulate and improve engrafted MSCs’*** on the intrinsic hormesis effects in cellular biology,we built a microglia-inspired MSC bioengineering system to transform detrimental high-level ROS and PC into vitality enhancers for strengthening MSC *** system is achieved by bioorthogonally arming metabolic glycoengineered MSCs with microglial membrane-coated nanoparticles and an antioxidative extracellular protective *** this system,extracellular ROSscavenging and PC-absorbing layers effectively buffer the deleterious effects and establish a microlivable niche at the level of a single MSC for ***,the infarct’s inanimate milieu is transformed at the tissue level into a new living niche to facilitate *** engineered MSCs achieved viability five times higher than natural MSCs at seven days after transplantation and exhibited a superior therapeutic effect for stroke recovery up to 2. *** vitality-augmented system demonstrates the potential to accelerate the clinical translation of MSC treatment and boost stroke recovery.

关键词： Ischemic stroke Mesenchymal stem cell Cell engineering Hormesis effect Bioorthogonal chemistry Microglia Reactive oxygen spices Proinflammatory cytokines

Removal of benzene homologous compounds with chlorine dioxide

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Journal of Environmental Sciences 1996年第3期8卷 321-327页

作者： Chen Hui Wei Dongbin(Chemistry department, Northwest normal {2., Lanzhou 730070,china)wang Shuyan Zhu Mingyang Liu Zhaochang(department of Environmental Engineering, Tsinghua {2., beijing 100084, china)Keng Zhu(Chemistry department, Pekin Chemistry department Northwest Normal University Lanzhou 730070 China Dept. of Environmental Engineering Tsinghua University Beijing 100084 China Chemistry department Peking University Beijing 100871 China

Chlorine dioxide composite disinfectant generator that produces a mixture of the oxidant gases comprising chlorine dioxide, chlorine, ozone and hydrogen peroxide through electrolyzing salt,is widely utilized in china *** experiments in the paper focused on the removal of benzene homologous compounds such as styrene, methyl and dimethyl benzene. The results indicated that pH value was the most crucial factor to influence the treatment effects while reaction time and input way were considered as the importance. The removal rate for benzene could reach 60% when above 80% for methyl, and 100% for styrene and dimethyl. The variation mechanisms between chlorine dioxide,chlorite and chloride which determine the drinking water quality also discussed.

关键词： Benzene homologous compounds chlorine dioxide drinking water treatment

A Hybrid of Theorems of Goldbach and Piatetski-Shapiro

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Chinese Annals of mathematics,Series B 2006年第3期27卷 341-352页

作者： Xianmeng MENG Mingqiang wang School of Computer Science and Technology, Shandong university, Jinan 2.0100,{2. department of Statistics and mathematics, Shandong Finance Institute, Jinan 2.0014,{2.. School of Computer Science and Technology, Shandong university, Jinan 2.0100,{2. department of mathematics, Qufu normal university, Qufu 2.3165, Shandong,{2.. School of Computer Science and Technology Shandong University Jinan 250100 China department of Statistics and mathematics Shandong Finance Institute Jinan 250014 China department of mathematics Qufu Normal University Qufu 273165 Shandong China

It is proved that for almost all sufficiently large even integers n, the prime variable equation n = p1 ＋ p2. p1 ∈ Pγ is solvable, with 13/15 〈γ≤ 1, where Pγ = {p ｜p = [m^1/γ], for integer m and prime p} is t... 详细信息

关键词： Circle method Sieve method Goldbach problem