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Acoustic Impedance Inversion Via Wavelet Transform Constraints

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Communications in Nonlinear Science and Numerical Simulation 1998年第1期3卷 3-5页

作者： Huiyan ZHANG and Bainian LU (Graduate school, Research institute of Petrolem Expl. & Dev. Beijing,100083,china) +(institute of Computational and Applied Mathematics, Xiangtan university, 411105, china) *(institute of Applied physics Graduate school Research Institute of Petrolem Expl. & Dev. Beijing 100083 China institute of Computational and Applied Mathematics Xiangtan University Xiangtan 411105 China institute of Applied physics and Computational Mathematics Beijing 100088 China Graduate school of china Academy of Engineering physics Beijing 100088 China

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ＩｎｔｒｏｄｕｃｔｉｏｎＷａｖｅｌｅｔｔｒａｎｓｆｏｒｍ，ＷＴ，ｔｈｅｏｒｙｈａｓｄｅｖｅｌｏｐｅｄｒａｐｉｄｌｙｄｕｒｉｎｇｔｈｅｌａｓｔｆｅｗｙｅａｒｓａｎｄｈａｓｂｅｅｎｓｕｃｃｅｓｆｕｌｙａｐｐｌｉｅｄｉｎｍａｎｙｄｉｆｅｒｅｎｔｆｉｅｌｄｓ...

关键词： acoustic impedance inversion wavelet transform priori scale information

Influence of Yb^(3+) concentration on the upconversion luminescence of oxyfluoride material doped with Er^(3+)

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Science china(physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3 1 institute of Optoelectronic Technology,Key Laboratory of Luminescence and Optical information (Beijing Jiaotong university),Ministry of Education,Beijing 100044,china 2 Department of physics,Chinese People’s Public Security university,Beijing 100038,china 3 physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya university,Menouf 32952,Egypt institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing China Department of physics Chinese People’s Public Security University Beijing China physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya university Menouf Egypt

In this paper,a new upconversion luminescent material co-doped with Erbium and Ytterbium is reported. The upconversion luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3+ concentration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upconversion mechanism.

关键词： upconversion luminescence Er3+ Yb3+

VERTICAL HEREDITY VS. HORIZONTAL GENE TRANSFER: A CHALLENGE TO BACTERIAL CLASSIFICATION

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Journal of Systems Science & Complexity 2003年第3期16卷 307-314页

作者： HAO Bailin(institute of theoretical physics, Academy of Chinese Sciences, Beijing 100080, china Senior International Fellow of the Santa Fe institute T-Life Research Center, Fudan university,Shanghai 200433, china)QI Ji(institute of theoretical physics, Beijing 100080, china) institute of theoretical physics Academy of Chinese Sciences 北京 100080 institute of theoretical physics Chinese Academy of Sciences 北京 100080

The diversity and classification of microbes has been a long-standing *** phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable tree of life in the late 1970s. How-ever, the availability of more and more complete bacterial genomes has brought about complications instead of refinement of the tree. In particular, it turns out that different choice of genes may tell different history. This might be caused by possible horizontal gene transfer (HGT) among species. There is an urgent need to develop phylogenetic methods that make use of whole genome data. We describe a new approach in molecular phylogeny,namely, tree construction based on K-tuple frequency analysis of the genomic *** aside the technicalities, we emphasize the transition from randomness to determin-ism when the string length K increases and try to comment on the challenge mentioned in the title.

关键词： prokaryote phylogeny horizontal gene transfer fitness compositionaldistance

A general information theoretical proof for the second law of thermodynamics

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Science china(physics,Mechanics & Astronomy) 2008年第7期51卷 813-816页

作者： ZHANG QiRen Department of Technical physics, Peking university, Beijing 100871, china Department of Technical physics Peking University Beijing China

It is shown that the conservation and the non-additivity of the information, together with the additivity of the entropy, make the entropy increase in an isolated system. The collapse of the entangled quantum state offers an example of the information non-additivity. Nevertheless, the non-additivity of information is also true in other fields in which the interaction information is important. Examples are classical statistical mechanics, social statistics and financial processes. The second law of thermodynamics is thus proven in its most general form. It is exactly true not only in quantum and classical physics but also in other processes in which the information is conservative and non-additive.

关键词： information conservation non-additivity of information entropy increase

PDMS prism-glass optical coupling for surface plasmon resonance sensors based on MEMS technology

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Science china(information Sciences) 2010年第10期53卷 2144-2158页

作者： GENG ZhaoXin 1,2 , LI Qing 3 , WANG Wei 1 & LI ZhiHong 1 1 institute of Microelectronics, Peking university, Beijing 100871, china 2 school of information engineering, Minzu university of china, Beijing 100081, china 3 school of Sciences, Changchun university of Science and Technology, Changchun 130000, china institute of Microelectronics Peking University Beijing China school of information engineering Minzu University of China Beijing China school of Sciences Changchun University of Science and Technology Changchun China

A miniaturized surface plasmon resonance (SPR) chip has been developed for biomedical and chem-ical analysis with low cost and high performance. The techniques of bulk silicon micromachining and polymer replication were used to fabricate the Kretschmann SPR sensor composed of a Polydimethylsiloxane (PDMS) prism, a coupling glass and microchannels. The plasmon properties of thin metal films were investigated theoret-ically based on Fresnel analysis, with optical boundary conditions pertaining to the surface plasmon resonance at the gold/water and gold/air interfaces. The theoretical results show that difference in the refractive index (RI) between the PDMS prism and the coupling glass layer affect the precision of the SPR angle and the SPR curve. Meanwhile, the period of the interference fringe attaching on the SPR curve increases with an increase in wavelength and a decrease in the refractive index of the coupling glass layer. The gold thickness of 50 nm is required while employing a fixed incident wavelength of 650 nm, to achieve optimum SPR excitation conditions and the sensor sensitivity. The characteristics of this SPR sensor were evaluated in the angular interrogation mode of employing the incident wavelength of 650 nm in air and water media, respectively. The obtained SPR angles were approximately consistent with the theoretical ones.

关键词： surface plasmon resolance polymer microfluidic PDMS

PREPARATION AND SURFACE CHARACTERIZATION OF TiO2 THIN FILMS ON GLASS BY MAGNETRON SPUTTERING METHOD

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 207-209页

作者： L.S.Yin1,3), H. Shen2) and J.X. Zhang3) 1)College of information Engineering, Central South university, Changsha 410075, china 2)Guangzhou institute of Energy Conversion, CAS, Guangzhou 510070, china 3)Department of physics, Zhongshan university, Guang Coll. of Info. Eng. Central South Univ. Changsha 410075 China

Ti thin films were firstly deposited on glass substrates by magnetron sputtering method, then sintered the Ti thin films in air atmosphere and finally TiO2 transparence thin films on glass substrates were obtained. The structure and surface morphologies of the thin films were characterized by X-ray diffraction and SEM. The growth process of the thin films has been observed. The annealing time and annealing temperatures have an affect on the growth of the films.

关键词： TiO2. thin film. magnetron sputtering

Excitation Spectrum of Spin-1 Bosonic Atoms in Mort Insulating Phase

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Communications in theoretical physics 2006年第1期 87-94页

作者： HOU Jing-Min~(1,2,+) TIAN Li-Jun~31 Department of physics,Southeast university,Nanjing 210096,china2 theoretical physics Division,Nankai institute of Mathematics,Nankai university,Tianjin 300071,china3 Department of physics,Shanghai university,Shanghai 200436,china

The effective action for spin-1 bosonic atom in an optical lattice is *** quasiparticle and quasiholedispersions are calculated for different cases by using a functional integral *** all cases,the excitation spectraar... 详细信息

关键词： collective excitations optical lattice Mott-insulating phase spinor atoms

Structures and stability of isomers of[C,N,N,P]system

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Science china Chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2, ZHONG Hua1, YU Haitao1, FU Honggang1,3 & SUN Jiazhong1,3 1. school of Chemistry and Materials Science, Heilongjiang university, Harbin 150080, china 2. school of Chemistry and Chemical Engineering, Qiqihar university, Qiqihar 161006, china 3. State Key Laboratory of theoretical and Computational Chemistry, institute of theoretical Chemistry, Jilin university, Changchun 130023, china school of Chemistry and Materials Science Heilongjiang University Harbin China school of Chemistry and Chemical Engineering Qiqihar University Qiqihar China Jilin university Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2df) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2A′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

Perturbative Painleve Analysis of General KdV System and Its Exact Soliton Solutions

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Communications in theoretical physics 2005年第8期44卷 197-202页

作者： LIN Ji YE Li-Jun LI Hua-Mei institute of Nonlinear physics, Zhejiang Normal university, Jinhua 321004, china institute of Nonlinear physics Zhejiang Normal University Jinhua 321004 China

Using the standard Painlevé analysis ad the perturbative method,the Painlevé test for the logarithmicbranch is investigated. Nine arbitrary functions are obtained and the B cklund transformation of the logarithmic b... 详细信息

关键词： Painlevé analysis perturbative method Jacobi elliptic solution