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Topological Vortices in Superfluid Films

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Communications in Theoretical Physics 2005年第1X期44卷 160-164页

作者： WANGJun-Ping duanyi-Shi InstituteofTheoreticalPhysics LanzhouUniversityLanzhou730000China InstituteofScienceandTechnologyforOpto-electronicInformation YantaiUniversityYantai264005China

We study the topological structure of the vortex system in a superfiuid film. Explicit expressions for the vortex density and velocity field as functions of the superfluid order parameter are derived. The evolution of... 详细信息

关键词：拓扑旋涡超流体拓扑结构旋涡密度

Contribution of Disclination Lines to Free Energy of Liquid Crystals in Single-Elastic Constant Approximation

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Communications in Theoretical Physics 2004年第2X期42卷 185-188页

作者： YANGGuo-Hong WANGYu-Sheng duanyi-Shi DepartmentofPhysics ShanghaiUniversityShanghai200436China InstituteofTheoreticalPhysics LanzhouUniversityLanzhou730000China

In the light of φ-mapping method and topological current theory, the contribution of disclination lines to free energy density of liquid crystals is studied in the single-elastic constant approximation. It is pointed out that the total free energy density can be divided into two parts. One is the usual distorted energy density of director field around the disclination lines. The other is the free energy density of disclination lines themselves, which is shown to be centralized at the disclination lines and to be topologically quantized in the unit of kπ /2. The topological quantum numbers are determined by the Hopf indices and Brouwer degrees of the director field at the disclination lines, i.e. the disclination strengths. From the Lagrange's method of multipliers, the equilibrium equation and the molecular field of liquid crystals are also obtained. The physical meaning of the Lagrangian multiplier is just the distorted energy density.

关键词：向错线自由能液晶单弹性常数近似拉格朗日多项式

The specific carbon isotopic compositions of branched and cyclic hydrocarbons from Fushun oil shale

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Chinese Science Bulletin 2004年第4期49卷 369-373页

作者： duanyi WUBaoxiang ZHENGGuodong ZHANGHui ZHENGChaoyang Lanzhou Institute of Geology Chinese Academy of SciencesLanzhou730000China GRC School of EngineeringCardiff University Cardiff CF24 0YFUnited Kingdom

Various branched and cyclic hydrocarbons are isolated from the Fushun oil shale and their carbon isotopes are determined. The analytical results show that the branched and cyclic hydrocarbons are fully separated from n-alkanes by 5 molecular-sieve adduction using long time and cold solvent. The branched and cyclic hydrocarbon frac-tion obtained by this method is able to satisfy the analytic requests of GC-IRMS. The carbon isotopic compositions of these branched and cyclic hydrocarbons obtained from the sample indicate that they are derived from photoautotrophic algae, chemoautotrophic bacteria (-33.4—-39.0) and methanotrophic bacteria (-38.4—-46.3). However the long-chain 2-methyl-branched alkanes indicate that their carbon isotopic compositions reflect biological origin from higher plants. The carbon isotopic composition of C30 4-methyl sterane (-22.1? is the heaviest in all studied ste- ranes, showing that the carbon source or growth condition for its precursor, dinoflagellate, may be different from that of regular steranes. The variation trend of d 13C values between isomers of hopanes shows that 13C-enriched precursors take precedence in process of their epimerization. Methanotro-phic hopanes presented reveal the processes of strong trans-formation of organic matter and cycling of organic carbon in the water column and early diagenesis of oil shale.

关键词：油页岩碳氢化合物抚顺市碳同位素化合物

A cumulative damage model for predicting and assessing raveling in asphalt pavement using an energy dissipation approach

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 949-962页

作者： Kailing DENG duanyi WANG Cheng TANG Jianwen SITU Luobin CHEN School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510640China

Raveling is a common distress of asphalt pavements,defined as the removal of stones from the pavement *** predict and assess raveling quantitatively,a cumulative damage model based on an energy dissipation approach has been developed at the meso *** construct the model,a new test method,the pendulum impact test,was employed to determine the fracture energy of the stone-mastic-stone meso-unit,while digital image analysis and dynamic shear rheometer test were used to acquire the strain rate of specimens and the rheology property of mastic,*** of the model reveals that when the material properties remain constant,the cumulative damage is directly correlated with loading time,loading amplitude,and loading ***,damage increases with superimposed linear and cosine variations over time.A higher stress amplitude results in a more rapidly increasing rate of damage,while a lower load frequency leads to more severe damage within the same loading ***,an example of the application of the model has been presented,showing that the model can be utilized to estimate failure life due to *** model is able to offer a theoretical foundation for the design and maintenance of anti-raveling asphalt pavements.

关键词： asphalt pavement raveling cumulative damage dissipation energy theory

Single-beam two-photon three-dimensional optical storage in a pyrryl-substituted fulgide photochromic material

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Chinese Science Bulletin 2001年第22期46卷 1856-1859页

作者： Ningfang Liao Mali Gong duanyi Xu Guosheng Qi Kai Zhang Tsing Hua Univ Dept Precis Instruments Beijing 100084 Peoples R China

We introduce a high-density three-dimensional optical data storage approach by using a pyrryl-sub-stituted fulgide photochromic material with a method of single-beam two-photon recording and fluorescence confocal readout. The detailed information about the photochromic material and the experimental setup are presented. The experiments about multi-layered recording and readout are carried out with a 100-μm-thick transparent photochromic material film. The results show that the lateral resolution is better than 1 μm, and the longitudinal resolution is about 3 μm. Besides, the readout times for the recorded data aredesirable when using a readout laser power smaller than 5 mW.

关键词： two-photon optical data storage photochromic material confocal microscope.

Optical Data Storage and Application Systems

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Optical Data Storage and Application Systems

Regulation of HIF-1 α to Expression of N-myc Downstream Regulated Gene 1 in Colorectal Carcinoma

1992 International Conference on Lasers and Optoelectronics(ICLOE’92)

作者： duanyi Xu Microengineering Institute Tsinghua University

＜正＞Progress of optical data storage technology and application systems,which have been obtained recent years in Tsinghua University,are *** this paper,the new multifuction optical drive,miniaturizational optical head,high speed precise seeking system,automatic exchange disk system（jukebox）, controller interface adapter,data compression technology and various applicaion systems are reported.

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Wuhan University Journal of Natural Sciences 2007年第3期12卷 563-568页

作者： ZHAO duanyi LIU Zhisu JIANG Congqing BANGOURA Gassimou WU Kailang WU Jianauo Department of Colorectal Surgery Zhongnan Hospital of Wuhan University Wuhan 430071 Hubei China College of Life Sciences Wuhan University/National Key Laboratory of Virology Wuhan 430072 Hubei China

Plasmid expressing small interfering RNA （siRNA） against HIF-1α （pSilence-2.1-U6-siRNA） was constructed and transfected into LS174T cells in hypoxia *** expression of siRNA against HIF-1 α in LS174T cells, expressions of HIF-1 α and N-myc downstream regulated gene 1 （NDRG1） gene were inhibited significantly. HIF-1 cta transcripts were positive in 67.7% （42/62） and 44.4% （8/18） of colorectal adenocarcinoma and adenoma, re- spectively. The mean percentage of cells with positive hybridization of HIF-1 α mRNA increases with the development from Duke stage A to stage C＋D （p〈 0.05）. The positive staining rate of NDRG1 protein was significant higher in than that in colorectal adenoma colorectal adenocarcinoma group group （p〈 0.05）. The level of HIF-1 a transcripts was positively correlated with the level of NDRG1 protein （p 〈 0.05） during colorectal tumor progression. HIF-1α and its down stream gene NDRG1 may play roles in tumor progression of human colorectal carcinoma.

关键词： hypoxia inducible factor-1 α (HIF-1 α ) N-myc downstream regulated gene 1 small interfering RNA colorectal carcinoma

RECENT ADVANCES IN CODED MODULATION FOR FADING CHANNELS

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RECENT ADVANCES IN CODED MODULATION FOR FADING CHANNELS

International Conference on Electronics and Information Technology

作者： Wang duanyi Hu Zhengming P.O.Box 190 Beijing Univ.of Posts Telecommun.Beijing 100088P.R.China

＜正＞The recent advances in coded modulation for fading channels in the last decade are reviewed in this *** constructive schemes suitable for Rayleigh fading channels are extensively *** systematic design method for efficient coded modulation on fading channel is summarized. Some proposed shemes are compared according to the design method.

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翁端怡主任运用“和”理念治疗小儿咳嗽经验

福建中医药 2024年第7期55卷 23-24页

作者：叶锦霞翁端怡福建中医药大学附属人民医院福建福州350004

翁端怡主任认为儿童咳嗽最常见病因为风邪、痰邪,根据邪之寒热、感邪深浅、病程发展阶段的不同,以“和”理念为指导思想,用药以寒温并用、宣降相因、散收结合、肺脾同治为特点,小儿感邪后常表现为寒热并见,多取麻桂-石膏、辛夷-败酱草... 详细信息

翁端怡主任认为儿童咳嗽最常见病因为风邪、痰邪,根据邪之寒热、感邪深浅、病程发展阶段的不同,以“和”理念为指导思想,用药以寒温并用、宣降相因、散收结合、肺脾同治为特点,小儿感邪后常表现为寒热并见,多取麻桂-石膏、辛夷-败酱草等药对寒温并用以调节寒热;治咳嗽当宣发肺气,可选用麻黄、杏仁等宣降相因之药,同时佐以香附、郁金、苏梗行气宽胸或佛手、莱菔子等助运通降之品;根据病程不同阶段进行施治,病初痰盛时以川贝母、海浮石等祛散痰邪,病末邪尽时以五味子、乌梅敛肺止咳;此外,治咳时适当佐以陈皮、姜半夏、炒麦芽等以培土生金,肺脾同治,可获良效。

关键词：小儿咳嗽 “和”理念寒温并用宣降相因散收结合肺脾同治