GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Two-dimensionally conjugated molecules: The importance of low molecular symmetry for large third-order nonlinear optical effects
    AIP Publishing ; 1998
    In:  Applied Physics Letters Vol. 73, No. 17 ( 1998-10-26), p. 2396-2398
    Details
    In: Applied Physics Letters, AIP Publishing, Vol. 73, No. 17 ( 1998-10-26), p. 2396-2398
    Abstract: Low molecular symmetry with regard to the conjugation path of the delocalized electrons was found to be a good guideline towards linearly conjugated molecules with large second-order hyperpolarizabilities γ. We show that this guideline is also valid for two-dimensionally conjugated systems. We experimentally demonstrate this by third-harmonic generation measurements of two-dimensionally conjugated organic molecules, and show that the observed effects can be explained by the symmetry of the electronic wave functions. In addition, the positive impact of the substitution of phenyl rings by thienyl rings on γ is discussed.
    Type of Medium: Online Resource
    ISSN: 0003-6951 , 1077-3118
    URL: Article
    DOI: 10.1063/1.122445
    RVK:
    UA 1000
    Language: English
    Publisher: AIP Publishing
    Publication Date: 1998
    detail.hit.zdb_id: 211245-0
    detail.hit.zdb_id: 1469436-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Heliospheric termination shock motion in response to LISM variations: Spherically symmetric model
    American Geophysical Union (AGU) ; 1997
    In:  Geophysical Research Letters Vol. 24, No. 13 ( 1997-07), p. 1659-1662
    Details
    In: Geophysical Research Letters, American Geophysical Union (AGU), Vol. 24, No. 13 ( 1997-07), p. 1659-1662
    Abstract: The unsteady spherically symmetric one‐dimensional gasdynamic model appears to be a powerful tool in the investigation of the termination shock motion. Such a model has previously been used to examine the response of the heliospheric termination shock to variations in upstream solar wind conditions [ Ratkiewicz et al., 1996]. In the current paper we apply the same model to study response of the shock to variations in the interstellar medium. The initial‐boundary conditions for the unsteady calculations are given by the pressure as a function of time on an outer boundary either alone or with the density as a function of time on an inner boundary. The motion of the termination shock is caused by fluctuations in both solar wind and interstellar plasma parameters and has a rather complicated behavior, characterized by a sequence of perturbations that hit the termination shock and are reflected from the outer boundary.
    Type of Medium: Online Resource
    ISSN: 0094-8276 , 1944-8007
    URL: Article
    DOI: 10.1029/97GL01537
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1997
    detail.hit.zdb_id: 2021599-X
    detail.hit.zdb_id: 7403-2
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Heliospheric termination shock motion due to fluctuations in the solar wind upstream conditions: Spherically symmetric model
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Space Physics Vol. 101, No. A12 ( 1996-12), p. 27483-27497
    Details
    In: Journal of Geophysical Research: Space Physics, American Geophysical Union (AGU), Vol. 101, No. A12 ( 1996-12), p. 27483-27497
    Abstract: Large‐scale fluctuations in the solar wind plasma upstream of the heliospheric termination shock (TS) will cause inward and outward motions of the shock. Using numerical techniques, we extend an earlier, strictly one‐dimensional (planar) analytic gasdynamic model [ Barnes , 1993] to spherical symmetry to investigate the features of global behavior of shock motion. Our starting point is to establish a steady numerical solution of the gasdynamic equations describing the interaction between the solar wind and the interstellar medium. We then introduce disturbances of the solar wind dynamic pressure at an inner boundary and follow the subsequent evolution of the system, especially the motion of the termination shock. Our model solves spherically symmetric gasdynamic equations as an initial‐boundary value problem. The equations in conservative form are solved using a fully implicit total variation diminishing (TVD) upwind scheme with Roe‐type Riemann solver. Boundary conditions are given by the solar wind parameters on an inner spherical boundary, where they are allowed to vary with time for unsteady calculations and by a constant pressure (roughly simulating the effect of the local interstellar medium) on an outer boundary. We find that immediately after the interaction, the shock moves with speeds given by the earlier analogous analytic models. However, as the termination shock propagates, it begins to slow down, seeking a new equilibrium position. In addition, the disturbance transmitted through the TS, either a shock or rarefaction wave, will encounter the outer boundary and be reflected back. The reflected signal will encounter the TS, causing it to oscillate. The phenomenon may be repeated for a number of reflections, resulting in a “ringing” of the outer heliosphere.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/96JA02233
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
    detail.hit.zdb_id: 161666-3
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Centrosymmetric or Noncentrosymmetric? Case Study, Generalization and Structural Redetermination of Sr 5 Nb 5 O 17
    International Union of Crystallography (IUCr) ; 1998
    In:  Acta Crystallographica Section B Structural Science Vol. 54, No. 4 ( 1998-08-01), p. 399-416
    Details
    In: Acta Crystallographica Section B Structural Science, International Union of Crystallography (IUCr), Vol. 54, No. 4 ( 1998-08-01), p. 399-416
    Abstract: The possibility that the structure of the novel semiconducting perovskite-related material strontium niobium oxide, Sr 5 Nb 5 O 17 , refined by Schmalle et al. [ Acta Cryst. (1995), C 51 , 1243–1246] in space group Pnn 2, might instead belong to space group Pnnm has been investigated following an analysis of the atomic coordinates that indicated the latter space group to be more likely. All I obs were carefully remeasured, first those within a hemisphere containing c * , then all that lay within the full sphere of reflection. Refinement was undertaken, with each of two different sets of weights, in each space group. Each data set was used under three limiting intensity conditions: I obs 〉 4σ( I obs ), I obs 〉 2σ( I obs ) and finally with all reflections, but setting magnitudes with I obs ≤ 0 equal to 0. Fourteen separate tests based only upon the X-ray diffraction data may be used to distinguish between Pnn 2 and Pnnm . Nine tests favored the latter choice, four were indeterminate and one was not used. Seven further tests may be made on the basis of physical measurement; of these, three strongly indicated Pnnm , one was indeterminate and three could not be used. The evidence clearly suggests the space group is Pnnm . The use of all reflections, including those with negative magnitude set equal to zero, is essential to avoid ambiguity in the X-ray diffraction tests and achieve the highest reliability. Refinement with weights based on variances of Type A and Type B [Schwarzenbach et al. (1995). Acta Cryst. A 51 , 565–569] resulted in improved reliability compared with that obtained from a popular empirical weighting scheme. The revised structure differs in several respects from that published previously.
    Type of Medium: Online Resource
    ISSN: 0108-7681
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    DOI: 10.1107/S0108768197019642
    DOI: 10.1107/S0108768197019642/br0066sup1.cif
    DOI: 10.1107/S0108768197019642/br0066A11sup2.sft
    DOI: 10.1107/S0108768197019642/br0066A21sup3.sft
    DOI: 10.1107/S0108768197019642/br0066A31sup4.sft
    DOI: 10.1107/S0108768197019642/br0066A41sup5.sft
    Language: Unknown
    Publisher: International Union of Crystallography (IUCr)
    Publication Date: 1998
    detail.hit.zdb_id: 6043-4
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    On the processes in the terrestrial magnetosheath: 2. Case study
    American Geophysical Union (AGU) ; 1999
    In:  Journal of Geophysical Research: Space Physics Vol. 104, No. A10 ( 1999-10), p. 22357-22373
    Details
    In: Journal of Geophysical Research: Space Physics, American Geophysical Union (AGU), Vol. 104, No. A10 ( 1999-10), p. 22357-22373
    Abstract: We test a new scheme to study the magnetosheath. The scheme uses the solar wind measurements as the input into the gasdynamic convected field model, and the model output is compared with magnetosheath observations. In our four test cases there is a significant overall success in the model prediction. This scheme works better than other methods in magnetosheath studies and is potentially useful for space weather forecasts and nowcasts. The direction of the magnetic field is modeled most accurately. The prediction of the size of the magnetosphere is accurate within a few percent. The predicted thickness of the magnetosheath is accurate up to 90%. With a double‐normalization procedure developed in this study, we are able to separate the processes intrinsic in the magnetosheath from those due to large‐scale upstream temporal variations. The test cases confirm the existence of a compressional front one third of the distance from the magnetopause to the bow shock near the stagnation streamline. The magnetosheath density profile near the stagnation streamline is consistent with the models that add a compressional front between the two depletion processes described by the plasma depletion model. A major unexpected feature is that the magnetosheath flow pattern is very different from that described by the model and maybe by most other models, including MHD models. The magnetosheath flow near the stagnation streamline does not slow down gradually toward the stagnation point. It moves rapidly until reaching a very small region near the magnetopause.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/1999JA900246
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1999
    detail.hit.zdb_id: 161666-3
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    On the processes in the terrestrial magnetosheath: 1. Scheme development
    American Geophysical Union (AGU) ; 1999
    In:  Journal of Geophysical Research: Space Physics Vol. 104, No. A10 ( 1999-10), p. 22345-22355
    Details
    In: Journal of Geophysical Research: Space Physics, American Geophysical Union (AGU), Vol. 104, No. A10 ( 1999-10), p. 22345-22355
    Abstract: We propose a new method to study the structure of the magnetosheath and thereby determine the underlying processes that create this structure. This method provides a systematic means of separating perturbations due to the solar wind variations from those generated within the magnetosheath. As a result, we are able to study the magnetosheath processes as well as the dynamic solar wind‐magnetopause interaction. We use the solar wind measurements from an upstream monitor as the input to the gasdynamic convected field model and then compare the model output with the in situ magnetosheath observations. We introduce three parameters to scale the model prediction to match the timings of the magnetopause crossing, bow shock crossing, and upstream variations. With this procedure the relationship between the upstream measurements and the magnetosheath observations and the location of the magnetosheath satellite relative to the magnetopause and bow shock boundaries are highly constrained. We then introduce a series of normalization procedures that provide the means to remove the effects of the solar wind variations. The systematic differences between the model prediction and observation indicate physical processes that are not included in the gasdynamic model. An application of this approach is presented in a companion paper.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/1999JA900247
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1999
    detail.hit.zdb_id: 161666-3
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Evidence for reverse draping of magnetosheath field around the magnetosphere in IMP 8 observations for northward interplanetary magnetic field
    American Geophysical Union (AGU) ; 1996
    In:  Journal of Geophysical Research: Space Physics Vol. 101, No. A6 ( 1996-06), p. 13321-13326
    Details
    In: Journal of Geophysical Research: Space Physics, American Geophysical Union (AGU), Vol. 101, No. A6 ( 1996-06), p. 13321-13326
    Abstract: Fedder and Lyon [1995] recently showed the results from a global three‐dimensional magnetohydrodynamic (MHD) model of the solar wind interaction with the Earth's magnetic field for northward interplanetary magnetic field (IMF) that exhibited a “tadpole”‐shaped closed magnetosphere. One consequence of this configuration is that the inner magnetosheath or boundary layer fields exhibit reverse draping at the flanks compared to what is expected from the classical gas dynamic picture. This reverse draping, which occurs as a result of nearcusp merging in the MHD model, appears to be present in the statistical field pattern observed on IMP 8 at x ≈ −25–31 R E . The implication is that boundary layer field configurations for northward IMF produce very different J × B forces on the local boundary layer plasma than would be inferred from classical draping and thus may be responsible for some of the observed IMF dependence of the low‐latitude boundary layer properties.
    Type of Medium: Online Resource
    ISSN: 0148-0227
    URL: Article
    DOI: 10.1029/96JA00509
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 1996
    detail.hit.zdb_id: 161666-3
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Electro-optic properties of the organic salt 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate
    AIP Publishing ; 1996
    In:  Applied Physics Letters Vol. 69, No. 1 ( 1996-07-01), p. 13-15
    Details
    In: Applied Physics Letters, AIP Publishing, Vol. 69, No. 1 ( 1996-07-01), p. 13-15
    Abstract: We show that the organic salt 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate (DAST) is a very interesting material for electro-optic applications in the near infrared. The electro-optic coefficients, namely r111, r221, r331, r113, r223, and r333, were determined in the spectral range of 700 up to 1535 nm using optical samples cut from large high quality bulk crystals. DAST combines large electro-optic coefficients, e.g., r111=77±8 pm/V at λ=800 nm and r111=47±8 pm/V at λ=1535 nm, with low dielectric constants, e.g., ε1=5.2±0.4. This combination leads to large polarization-optical coefficients.
    Type of Medium: Online Resource
    ISSN: 0003-6951 , 1077-3118
    URL: Article
    DOI: 10.1063/1.118101
    RVK:
    UA 1000
    Language: English
    Publisher: AIP Publishing
    Publication Date: 1996
    detail.hit.zdb_id: 211245-0
    detail.hit.zdb_id: 1469436-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Tetraethynylethene molecular scaffolding: Nonlinear optical, redox, and amphiphilic properties of donor functionalized polytriacetylene and expanded radialenes
    Wiley ; 1997
    In:  Advanced Materials Vol. 9, No. 4 ( 1997-04), p. 339-343
    Details
    In: Advanced Materials, Wiley, Vol. 9, No. 4 ( 1997-04), p. 339-343
    Abstract: Polymers with polytriacetylene (PTA) backbone (see the Figure), and also expanded radialenes (a new class of macrocycles with large conjugated all‐carbon cores), are of interest because of their intrinsic two‐dimensional π‐electron conjugated pathways. The synthesis, electrochemical characteristics, and linear and nonlinear optical properties of donor‐functionalized polytriacetylene and donor end‐capped expanded radialenes are reported and discussed. magnified image
    Type of Medium: Online Resource
    ISSN: 0935-9648 , 1521-4095
    URL: Issue
    URL: Article
    DOI: 10.1002/adma.v9:4
    DOI: 10.1002/adma.19970090412
    RVK:
    UA 1538
    Language: English
    Publisher: Wiley
    Publication Date: 1997
    detail.hit.zdb_id: 1012489-5
    detail.hit.zdb_id: 1474949-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    One- and Two-Dimensionally Conjugated Tetraethynylethenes:  Structure versus Second-Order Optical Polarizabilities
    American Chemical Society (ACS) ; 1998
    In:  The Journal of Physical Chemistry B Vol. 102, No. 1 ( 1998-01-01), p. 29-32
    Details
    In: The Journal of Physical Chemistry B, American Chemical Society (ACS), Vol. 102, No. 1 ( 1998-01-01), p. 29-32
    Type of Medium: Online Resource
    ISSN: 1520-6106 , 1520-5207
    URL: Article
    DOI: 10.1021/jp971918o
    RVK:
    VA5430.B
    Language: English
    Publisher: American Chemical Society (ACS)
    Publication Date: 1998
    detail.hit.zdb_id: 1357799-2
    detail.hit.zdb_id: 2006039-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...