The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform

John Wang - One of the best experts on this subject based on the ideXlab platform.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    Journal of Applied Crystallography, 2014
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal-space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry. The lattice parameters of single-crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of the raw unit Cell, and subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation. Two methods of this procedure are described: in three-dimensional reciprocal space and in six-dimensional G6 space. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 A for the lattice parameter of indium tin oxide film. This new RSV method provides a practical and concise route to the crystal structure study of epitaxial thin films and could also be applied to the investigation of surface and interface structures.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    arXiv: Materials Science, 2013
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry (HR-XRD). The lattice parameters of single crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of raw unit Cell, subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation.Two methods of this procedure are described in 3D reciprocal space and 6D G6-space, respectively. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 {\AA} for the lattice parameter of ITO (Indium tin oxide) film. This new RSV method provides a practical and concise route to crystal structure study of epitaxial thin films, which could also be applied to the investigation of surface and interface structures.

Ping Yang - One of the best experts on this subject based on the ideXlab platform.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    Journal of Applied Crystallography, 2014
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal-space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry. The lattice parameters of single-crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of the raw unit Cell, and subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation. Two methods of this procedure are described: in three-dimensional reciprocal space and in six-dimensional G6 space. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 A for the lattice parameter of indium tin oxide film. This new RSV method provides a practical and concise route to the crystal structure study of epitaxial thin films and could also be applied to the investigation of surface and interface structures.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    arXiv: Materials Science, 2013
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry (HR-XRD). The lattice parameters of single crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of raw unit Cell, subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation.Two methods of this procedure are described in 3D reciprocal space and 6D G6-space, respectively. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 {\AA} for the lattice parameter of ITO (Indium tin oxide) film. This new RSV method provides a practical and concise route to crystal structure study of epitaxial thin films, which could also be applied to the investigation of surface and interface structures.

Peter W Barlow - One of the best experts on this subject based on the ideXlab platform.

  • Patterned Cell development in the secondary phloem of dicotyledonous trees: a review and a hypothesis
    Journal of Plant Research, 2006
    Co-Authors: Peter W Barlow, Jacqueline Lück
    Abstract:

    The secondary phloem of dicotyledonous trees and shrubs is constructed of sieve tube Cells (S) and their companion Cells, as well as parenchyma (P) and fibre (F) Cells. Different species have characteristic sequences of these S, P and F Cells within the radial files of their phloem. The sequences are recurrent, and are evidence of rhythmic Cell Determination and differentiation. A model was devised to account for the sequences found in various dicot tree species. It is based on the pattern of radial displacement of Cells through a gradient of morphogen which supports secondary phloem development. According to this model, each tree species shows a particular pattern of post-mitotic Cellular displacement along each radial file as a result of a corresponding sequence of periclinal division in the cambial initial and its descendents. The divisions and displacements ensure that at each timestep (equivalent to an interdivisional interval) each Cell resides in a specific location within the morphogenic gradient. Cells then emerge from the post-mitotic zone of Cell Determination, having acquired different final positional values. These values lie above a series of thresholds that permit the respective Determination and subsequent differentiation of one or other of the three Cell types S, P and F. The recurrent nature of the sequences of the three Cell types within each radial Cell file, as well as their tangential banding, are a consequence of a shared rhythmic spatio-temporal pattern of periclinal cambial divisions. With a single set of morphogen parameters required for Cell Determination, and using three positions for cambial Cell divisions, all the Cellular sequences of secondary phloem illustrated in the literature can be accounted for.

  • patterned Cell Determination in a plant tissue the secondary phloem of trees
    BioEssays, 2005
    Co-Authors: Peter W Barlow
    Abstract:

    The secondary vascular tissues (xylem and phloem) of woody plants originate from a vascular cambium and develop as radially oriented files of Cells. The secondary phloem is composed of three or four Cell types, which are organised into characteristic recurrent Cellular sequences within the radial Cell files of this tissue. There is a gradient of auxin (indole acetic acid) across both the cambium and the immediately postmitotic Cells within the xylem and phloem domains, and it is believed that this morphogen, probably in concert with other morphogenic factors, is closely associated with the Determination and differentiation of the different Cells types in each tissue. A hypothesis is developed that, in conjunction with the positional values conferred by the graded radial distribution of morphogen, Cell divisions at particular positions within the cambium are sufficient to determine not only each of the phloem Cell types but also their recurrent pattern of differentiation within each radial Cell file. BioEssays 27: 533–541, 2005. © 2005 Wiley periodicals, Inc.

Huajun Liu - One of the best experts on this subject based on the ideXlab platform.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    Journal of Applied Crystallography, 2014
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal-space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry. The lattice parameters of single-crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of the raw unit Cell, and subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation. Two methods of this procedure are described: in three-dimensional reciprocal space and in six-dimensional G6 space. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 A for the lattice parameter of indium tin oxide film. This new RSV method provides a practical and concise route to the crystal structure study of epitaxial thin films and could also be applied to the investigation of surface and interface structures.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    arXiv: Materials Science, 2013
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry (HR-XRD). The lattice parameters of single crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of raw unit Cell, subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation.Two methods of this procedure are described in 3D reciprocal space and 6D G6-space, respectively. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 {\AA} for the lattice parameter of ITO (Indium tin oxide) film. This new RSV method provides a practical and concise route to crystal structure study of epitaxial thin films, which could also be applied to the investigation of surface and interface structures.

Lang Chen - One of the best experts on this subject based on the ideXlab platform.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    Journal of Applied Crystallography, 2014
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal-space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry. The lattice parameters of single-crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of the raw unit Cell, and subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation. Two methods of this procedure are described: in three-dimensional reciprocal space and in six-dimensional G6 space. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 A for the lattice parameter of indium tin oxide film. This new RSV method provides a practical and concise route to the crystal structure study of epitaxial thin films and could also be applied to the investigation of surface and interface structures.

  • unit Cell Determination of epitaxial thin films based on reciprocal space vectors by high resolution x ray diffractometry
    arXiv: Materials Science, 2013
    Co-Authors: Ping Yang, Huajun Liu, Zuhuang Chen, Lang Chen, John Wang
    Abstract:

    A new approach, based on reciprocal space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry (HR-XRD). The lattice parameters of single crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of raw unit Cell, subsequent conversion to the Niggli unit Cell and the Bravais unit Cell by matrix calculation.Two methods of this procedure are described in 3D reciprocal space and 6D G6-space, respectively. The estimation of standard error in the lattice parameters derived by this new approach is discussed. The whole approach is illustrated by examples of experimental data. The error of the best result is 0.0006 {\AA} for the lattice parameter of ITO (Indium tin oxide) film. This new RSV method provides a practical and concise route to crystal structure study of epitaxial thin films, which could also be applied to the investigation of surface and interface structures.