15 resultados para non-destructive reconstruction

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Fulgides are one kind of organic photochromic compound, which are famous for their thermal irreversibility. In this report, from the difference spectra of the absorption A() of one kind of pyrrylfulgide, the spectral refractive index change n() was calculated by the Kramers-Kronig relation (KKR), and a good correlation of theoretically derived values and the experimental values of the n measured by a modified Michelson interferometer was found. Further, it is demonstrated that it was possible to calculate the spectral dependence of diffraction efficiency from the easily accessible absorption changes. This method will be a useful tool for the characterization and optimization of fulgide films. The results show that the diffraction efficiency is high at 488 and 750 nm, where the absorption is very small, so we can realize non-destructive reconstruction.

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It is to investigate molecule interactions between antigen and antibody with ellipsometric imaging technique and demonstrate some features and possibilities offered by applications of the technique. Molecule interaction is an important interest for molecule biologist and immunologist. They have used some established methods such as immufluorcence, radioimmunoassay and surface plasma resonance, etc, to study the molecule interaction. At the same time, experimentalists hope to use some updated technique with more direct visual results. Ellipsometric imaging is non-destructive and exhibits a high sensitivity to phase transitions with thin layers. It is capable of imaging local variations in the optical properties such as thickness due to the presence of different surface concentration of molecule or different deposited molecules. If a molecular mono-layer (such as antigen) with bio-activity were deposited on a surface to form a sensing surface and then incubated in a solution with other molecules (such as antibody), a variation of the layer thickness when the molecules on the sensing surface reacted with the others in the solution could be observed with ellipsometric imaging. Every point on the surface was measured at the same time with a high sensitivity to distinguish the variation between mono-layer and molecular complexes. Ellipsometric imaging is based on conventional ellipsometry with charge coupled device (CCD) as detector and images are caught with computer with image processing technique. It has advantages of high sensitivity to thickness variation (resolution in the order of angstrom), big field of view (in square centimeter), high sampling speed (a picture taken within one second), and high lateral resolution (in the order of micrometer). Here it has just shown one application in study of antigen-antibody interaction, and it is possible to observe molecule interaction process with an in-situ technique.

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概述了绿松石的使用历史和产地来源。利用质子激发X射线荧光光谱(PIXE)、X射线衍射(XRD)及扫描电镜(SEM)技术对来自伊朗、湖北郧县和西藏等地的绿松石样品进行岩石矿物学特征分析,从成分组成方面探讨绿松石的呈色机理。结果显示,不同产地、不同质地绿松石的成分组成存在较大差别,但主成分含量基本一致;绿松石的颜色主要由其中CuO和Fe2O3的含量比值变化决定,比值由大至小,实现了绿松石颜色由天蓝色到绿色的转变。

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蛇纹石玉是我国利用最早的玉石之一。采用外束质子激发x射线荧光(PIXE)、x射线衍射(XRD)和拉曼光谱(Raman)技术对我国出土的古玉器以及辽宁省岫岩县出产的蛇纹石玉石进行矿物特征分析。通过对古玉器和玉石的对比研究,成功地对古玉器中的蛇纹石质玉器进行了无损鉴定,总结得出了蛇纹石质古玉器的无损鉴别方法,对于深化我国古玉器的研究具有重要意义。微量元素特征分析有助于探索古玉器玉料的来源。

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河南南阳独山玉的开采历史可以追溯到新石器时代,在我国玉文化中占有重要地位。鉴于当前对独山玉进行无损鉴别的方法较少,利用质子激发X荧光技术(proton induced X-ray emission,PIXE)、X射线衍射(X-ray diffraction,XRD)、激光Raman光谱(laser Raman spectroscopy,LRS)和扫描电子显微镜(scanning electron microscope,SEM)等技术对河南南阳独山玉料进行岩石矿物学分析。结果表明:独山玉主要由钙长石矿物构成,晶粒细小且结合紧密的显微结构与独山玉具有极高的稳定性有较大关系。PIXE,XRD和Raman技术作为无损分析方法为鉴定独山玉提供了准确有效的方法,为研究贵重的古玉样品提供了技术支持。

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Optical waveguide propagation loss measurement method based on optical multiple reflections detection is presented in this paper. By using a precision reflectometer, uncertain influence on waveguide propagation loss measurement caused by fiber-waveguide coupling can be eliminated effectively and the waveguide net propagation loss can be measured accurately. To demonstrate this, the propagation loss of a Silicon-on-Insulator (SOI) rib waveguide fabricated by RIE is measured with the obtained value being 4.3 dB/cm. This method provides a non-destructive means for evaluating waveguide propagation loss. (c) 2005 Elsevier B.V. All rights reserved.

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The ground and excited state excitonic transitions of stacked InAs self-organized quantum dots (QDs) in a laser diode structure are studied. The interband absorption transitions of QDs are investigated by non-destructive PV spectra, indicating that the strongest absorption is related to the excited states with a high density and coincides with the photon energy of lasing emission. The temperature and excitation (electric injection) intensity dependences of photoluminescence and electroluminescence indicate the influence of state filling effect on the luminescence of threefold stacked QDs. The results indicate that different coupling channels exist between electronic states in both vertical and lateral directions.

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We present photoelectron spectroscopic and low energy electron diffraction measurements of water adsorption on flat Si samples of the orientations (001), (115), (113), (5,5,12) and (112) as well as on curved samples covering continuously the ranges (001)-(117) and (113)-(5,5,12)-(112). On all orientations, water adsorption is dissociative (OH and H) and non-destructive. On Si(001) the sticking coefficient S and the saturation coverage Theta(sat) are largest. On Si(001) and for small miscuts in the [110]-azimuth, S is constant nearly up to saturation which proves that the kinetics involves a weakly bound mobile precursor state. For (001)-vicinals with high miscut angles (9-13 degrees), the step structure breaks down, the precursor mobility is affected and the adsorption kinetics changed. On (115), (113), (5,5,12) and (112), the values of S and Theta(sat) are smaller which indicates that not all sites are able to dissociate and bind water. For (113) the shape of the adsorption curves Theta versus exposure shows the existence of two adsorption processes, one with mobile precursor kinetics and one with Langmuir-like kinetics. On (5,5,12), two processes with mobile precursor kinetics are observed which are ascribed to adsorption on different surface regions within the large surface unit cell. From the corresponding values of S and Theta(sat), data for structure models are deduced. (C) 1997 Elsevier Science B.V.

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The ground and excited state excitonic transitions of stacked InAs self-organized quantum dots (QDs) in a laser diode structure are studied. The interband absorption transitions of QDs are investigated by non-destructive PV spectra, indicating that the strongest absorption is related to the excited states with a high density and coincides with the photon energy of lasing emission. The temperature and excitation (electric injection) intensity dependences of photoluminescence and electroluminescence indicate the influence of state filling effect on the luminescence of threefold stacked QDs. The results indicate that different coupling channels exist between electronic states in both vertical and lateral directions.

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为了在线、实时、无损检测高温高压条件下运行的加氢反应器的多层器壁中原子氢的渗透速率和在任何指定剖面上的体浓度分布,发展了一种新型的检测技术.介绍了检测仪的结构设计及其特征。

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With development of industry and acceleration of urbanization, problems of air quality as well as their influences on human health have recently been regarded highly by current international communities and governments. Generally, industrializations can result in exhausting of a lot of industry gases and dusts, while urbanization can cause increasing of modern vehicles. Comparing with traditional chemical methods, magnetic method is simple, rapid, exact, low-cost and non-destructive for monitoring air pollution and has been widely applied in domestic and international studies. In this thesis, with an aim of better monitoring air pollution, we selected plants (highroad-side perennial pine trees (Pinus pumila Regel) along a highroad linking Beijing City and the Capital International Airport, and tree bark and tree ring core samples (willow, Salix matsudana) nearby a smelting industry in northeast Beijing) for magnetic studies. With systemic magnetic measurements on these samples, magnetic response mechanism of contamination(e.g. tree leaves, tree ring)to both short- and long-term environmental pollution has been constructed, and accordingly the pollution range, degree and process of different time-scale human activities could be assessed. A series of rock magnetic experiments of tree leaves show that the primary magnetic mineral of leaf samples was identified to be magnetite, in pseudo-single domain (PSD) grain size range of 0.2-5.0 μm. Magnetite concentration and grain size in leaves are ascertained to decrease with increasing of sampling distance to highroad asphalt surface, suggesting that high magnetic response to traffic pollution is localized within a distance of about 2 m away from highroad asphalt surface. On the other hand, highroad-side trees and rainwater can effectively reduce the concentration of traffic pollution-induced particulate matters (PMs) in the atmosphere. This study is the first time to investigate the relationship of smelting factory activities and vicissitudes of environment with tree rings by magnetic methods. Results indicate that magnetic particles are omnipresent in tree bark and trunk wood. Magnetic techniques including low-temperature experiment, successive acquisition of IRM, hysteresis loops and SIRM measurements suggest that magnetic particles are predominated by magnetite in pseudo-single domain state. Comparison of magnetic properties of tree trunk and branch cores collected from different directions and heights implies that collection of magnetic particles depends on both sampling direction and height. Pollution source-facing tree trunk wood contains significantly more magnetic particles than other sides. These indicate that magnetic particles are most likely intercepted and collected by tree bark first, then enter into tree xylem tissues by translocation during growing season, and are finally enclosed in a tree ring by lignifying. Correlation between magnetic properties such as time-dependent SIRM values of tree ring cores and the annual steel yields of the smelting factory is significant. Considering the dependence of magnetic properties in sampling directions, heights, and ring cores, we proposed that magnetic particles in the xylem cannot move between tree rings. Accordingly, the SIRM and some other magnetic parameters of tree ring cores from the source-facing side could be contributed to historical study of atmospheric pollution produced by heavy metal smelting activities, isoline diagrams of SIRM values of all the tree rings indicate that air pollution is increasing worse. We believed that a synthetic rock magnetic study is an effective method for determining concentration and grain size of ferromagnets in the atmospheric PMs, and then it should be a rapid and feasible technique for monitoring atmospheric pollution.

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It has been a difficult problem faced by seismologists for long time that how exactly to reconstruct the earth's geometric structure and distribution of physical attributes according to seismic wave's kinematical and dynamic characteristics, obtained in seismological observation. The jointing imaging of seismic reflector and anisotropy attributes in the earth interior is becoming the research hot spot. The limitation of shoot and observation system makes that the obtained seismic data are too scarce to exactly reconstruct the geological objects. It is popular that utilizing only seismic reflection traveltimes or polarizations information make inversion of the earth's velocity distribution by fixing seismic reflector configuration (vice versa), these will lead to the serious non-uniqueness reconstruction due to short of effective data, the non-uniqueness problem of reconstructing anisotropy attributes will be more serious than in isotropy media. Obviously it is not enough to restrict the media structure only by information of seismic reflection traveltimes or polarizations, which even sometimes will lead to distorted images and misinterpretation of subsurface structure. So we try to rebuild seismic reflection structure (geometry) and media anisotropic structure (physics) in the earth interior by jointing data of seismic wave kinematics and dynamics characteristics, we carry out the new experiment step by step, and the research mainly comprises of two parts: one is the reconstruction of P-wave vertical velocity and anisotropic structure(Thomsen parameter s and 8) in the transversely isotropic media with vertical symmetrical axis(VTI) by fixing geometrical structure, and the other is the simultaneous inversion of the reflector surface conformation and seismic anisotropic structure by jointing seismic reflection traveltimes and polarizations data. Simulated annealing method is used to the first research part, linear inversion based on BG theory and Simulated annealing are applied to the second one. All the research methods are checked by model experiments, then applied to the real data of the wide-angle seismic profile from Tunxi, Anhui Province, to Wenzhou, Zhejiang Province. The results are as following The inversion results based on jointing seismic PP-wave or PSV-wavereflection traveltimes and polarizations data are more close to real model than themodels based simply on one of the two data respectively. It is shown that the methodwe present here can effectively reconstruct the anisotropy attributes in the earth'sinterior when seismic reflector structure is fixed.The layer thickness, P-wave vertical velocity and Thomsen anisotropicparameters {s and 8) could be resolved simultaneously by jointing inversion ofseismic reflection traveltimes and polarizations with the linear inversion methodbased on BG theory.The image of the reflector structure, P-wave vertical velocity and theanisotropy parameters in the crust could be obtained from the wide-angle seismicprofile from Tunxi (in Anhui Province), to Wenzhou (in Zhejiang Province). Theresults reveal the difference of the reflector geometrical structure and physicalattributes in the crust between Yangtze block and Cathaysia block, and attempt tounderstand the characteristics of the crustal stress field in the areas.

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The sinipercids represent a group of 12 species of freshwater percoid fish, including nine in Siniperca and three species in Coreoperca. Despite several classification attempts and a preliminary molecular phylogeny, the phylogenetic relationships and systematic position of sinipercids remained still unsolved. The complete cytochrome b gene sequences from nine sinipercid species four non-sinipercid fish species were cloned, and a total of 12 cyt b sequences from 10 species of sinipercids and 11 cyt b sequences from 10 species of non-sinipercid fish also in Perciformes were included in the phylogenetic analysis. As expected, the two genera Siniperca and Coreoperca within sinipercids are recovered as monophyletic. However, nine species representing Moronidae, Serranidae, Centropomidae, Acropomatidae, Emmelichtyidae, Siganidae and Centrarchidae included in the present study are all nested between Coreoperca and Siniperca, which provides marked evidence for a non-monophyly of sinipercid fishes. Coreoperca appears to be closest to Centrachus representing the family Centrarchidae. Coreoperca whiteheadi and C. herzi are sibling species, which together are closely related to C. kawamebari. In the Siniperca, the node between S. roulei and the remaining species is the most ancestral, followed by that of S. fortis. S. chuatsi and S. kneri are sibling species, sister to S. obscura. However, the sinipercids do not seem to have a very clear phylogenetic history, for different methods of phylogenetic reconstruction result in different tree topologies, and the only conclusive result in favor of a paraphyletic origin of the two sinipercid genera is the parametric bootstrap test. The paraphyly of Sinipercidae may suggest that the "synapomorphs" such as cycloid scales, upon which this family is based, were independently derived at least twice within sinipercid fishes, and further study should be carried out to include the other two Siniperca species and to incorporate other genes.

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松鼠科隶属于哺乳纲、啮齿目,是一类世界广布性动物,全世界共计36 属 234 种。本文通过形态分析及分子生物学方法,研究了我国松鼠科动物的分类及 系统发育关系,内容包括以下两个方面: 一、中国松鼠科动物的分类 本研究查看了中科院昆明动物研究所、中科院动物研究所、云南大学、四川 省林业科学研究院、四川大学、陕西师范大学、陕西动物研究所、西北大学、上 海自然历史博物馆、广东昆虫所馆藏该科各类群标本。同时,结合相关文献,对 各类群的外形特征进行了详细的描述和系统分类整理,我国共计10 属34 种。测 取可量性状数据共计20800 个(完整头骨共计1300 号),而且还运用多变量及单 变量分析方法进行数据分析,对部分类群的种下分类结果进行分析:1.探讨了分 布于中国境内的明纹花鼠(Tamiops mcclellandii)3 亚种的有效性。2.研究了 隐纹花鼠(Tamiops swinhoei)在中国的分化并描记了分布于四川马尔康地区的 隐纹花鼠为一新亚种(Tamiops swinhoei markamensis)。3.描记了分布于云南 省东北部昭通地区的赤腹松鼠为一新亚种:昭通亚种(Callosciurus erythraeus zhaotongensis)。4. 提出了分布于云南省无量山区的泊氏长吻松鼠为一新亚种: 无量山亚种(Dremomys pernyi wuliangshanensis)。 二、中国松鼠科动物的系统发育研究 2004-2005 年相继到滇西北高黎贡山、香格里拉,滇西南临沧地区,滇东 南马关、麻栗坡、富宁,滇东北昭通地区进行标本采集,基本收集到我国南方松 鼠科属、种样品进行分子生物学研究。 1.中国松鼠科动物各属的系统发育关系 在分析线粒体细胞色数b 基因(1040bp)序列的基础上,运用贝叶斯法 (Bayesian phylogenetic reconstruction approaches)、最简约法(Maximum parsimony method)、邻接法(Neighbor Joining method)构建中国松鼠科动物 所有属间系统发育树。结果表明:所分析的10 属分别聚集为3 群,巨松鼠属Ratufa单独成为一群,丽松鼠属Callosciurus、长吻松鼠属Dremomys、花松鼠属 Tamiops 以及线松鼠属Menetes 成为一群,松鼠属Sciurus、岩松鼠属 Sciurotamias、花鼠属Tamias、旱獭属Marmota 以及黄鼠属Spermophilus 成 为一群。在此基础上我们进一步探讨了中国松鼠科动物的分化与环境变化的关 系。 2.长吻松鼠属的系统发育关系 在分析线粒体细胞色数b 基因(378bp)序列的基础上,我们重建了长吻松 鼠属内5 个类群间的系统发育关系,结合对5 类群外部形态特征的详细比较,我 们探讨并论证了红腿长吻松鼠、橙喉长吻松鼠作为种的地位的有效性,同时论证 了该属内泊氏长吻松鼠最早分化,其次为橙腹长吻松鼠,第三是红腿长吻松鼠, 红颊长吻松鼠和橙喉长吻松鼠是最后分化的类群。