scholarly journals A Comparative Study of Two Bicyclic Ethers, Eucalyptol and 1,4-Cineole, by Broadband Rotational Spectroscopy

2016 ◽  
Vol 230 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Chris Medcraft ◽  
Melanie Schnell
Keyword(s):  
Fourier Transform ◽  
Comparative Study ◽  
Functional Group ◽  
Three Dimensional ◽  
Microwave Spectroscopy ◽  
Dimensional Structure ◽  
Rotational Spectroscopy ◽  
Chirped Pulse ◽  
Three Dimensional Structure ◽  
Rotational Spectra

AbstractThe rotational spectra of the two structurally related molecules, 1,4-cineole and 1,8-cineole (eucalyptol), were measured between 2–8.5 GHz with chirped pulse Fourier transform microwave spectroscopy. The structures of these two molecules only differ in the connectivity of an ether functional group. This results in a significant change in the three dimensional structure of the molecule and consequently large differences in the rotational spectra. Only one conformer of each molecule was detected in the molecular jet and no line splittings due to internal rotations were detected. A substitution structure (

scholarly journals Generation and structural characterization of Ge carbides GeCn (n = 4, 5, 6) by laser ablation, broadband rotational spectroscopy, and quantum chemistry

2019 ◽  
Vol 21 (35) ◽  
pp. 18911-18919
Author(s):  
Kin Long Kelvin Lee ◽  
Sven Thorwirth ◽  
Marie-Aline Martin-Drumel ◽  
Michael C. McCarthy
Keyword(s):  
Fourier Transform ◽  
Laser Ablation ◽  
Structural Characterization ◽  
Quantum Chemical ◽  
Microwave Spectroscopy ◽  
Rotational Spectroscopy ◽  
Chirped Pulse ◽  
Rotational Spectra ◽  
High Level

Rotational spectra of three Ge carbides, linear GeC4, GeC5, and GeC6 have been observed using chirped pulse and cavity Fourier transform microwave spectroscopy via laser ablation, guided by new high-level quantum chemical calculations.

scholarly journals Electron-withdrawing effects on the molecular structure of 2- and 3-nitrobenzonitrile revealed by broadband rotational spectroscopy and their comparison with 4-nitrobenzonitrile

2018 ◽  
Vol 20 (34) ◽  
pp. 22210-22217 ◽  
Author(s):  
Jack B. Graneek ◽  
William C. Bailey ◽  
Melanie Schnell
Keyword(s):  
Molecular Structure ◽  
Fourier Transform ◽  
Microwave Spectroscopy ◽  
Rotational Spectroscopy ◽  
Frequency Range ◽  
Chirped Pulse ◽  
Rotational Spectra ◽  
Fourier Transform Microwave Spectroscopy

The rotational spectra of 2- and 3-nitrobenzonitrile were recorded via chirped-pulse Fourier transform microwave spectroscopy in the frequency range of 2–8 GHz.

scholarly journals Rotational spectra of van der Waals complexes: pyrrole–Ne and pyrrole–Ne2

2020 ◽  
Vol 22 (44) ◽  
pp. 25652-25660 ◽  
Author(s):  
Isabel Peña ◽  
Carlos Cabezas
Keyword(s):  
Fourier Transform ◽  
Van Der Waals ◽  
Microwave Spectroscopy ◽  
Frequency Region ◽  
Van Der Waals Complexes ◽  
Chirped Pulse ◽  
Rotational Spectra ◽  
Fourier Transform Microwave Spectroscopy

Rotational spectra of van der Waals complexes pyrrole–Ne and pyrrole–Ne2 have been investigated by chirped pulse Fourier transform microwave spectroscopy in the 2–8 GHz frequency region.

The Superposition of Caledonoid Folds on an Older Fold-System in the Dalradians of Malin Head, Co. Donegal

1954 ◽  
Vol 91 (6) ◽  
pp. 417-444 ◽  
Author(s):  
Doris L. Reynolds ◽  
Arthur Holmes
Keyword(s):  
Comparative Study ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Three Dimensional Structure ◽  
Fold System ◽  
Geological Map ◽  
Plasticine Models

AbstractIn the Malin Head promontory an Older fold-system, with thrusting and folding about N.W.-trending axes, was followed by Caledonoid folding about N.E.-trending axes. The limbs of the Older folds, both major and minor, now lie in the sheet- dip of the Caledonoid folds, the dips of the Caledonoid limbs being equivalent to the plunges of the axes of the Older folds. Most of the S-planes are shared in common by the two fold-systems. The only exceptions are those that outline the closures and rising parts of the Older fold-system, and these form zones in which the S-planes strike at right angles to the Caledonoid trend. By reference to the outcrop-forms in the area described, and with the aid of plasticine models, it is demonstrated that the outcrop-forms of folded folds are readily recognjzable, and that they provide visible evidence of the approximate axial directions and relative ages of the two fold-systems. By comparative study of outcrop-forms on the models and structures seen in sections cut at right angles to each of the fold-axes, it is found that the structures differ radically from those constructed by projecting the outcrop-forms on planes normal to the axes. The “down-the-plunge” method of viewing a geological map thus provides no clue to the actual three-dimensional structure of folded folds.

Reconstruction of Three Dimensional Structures from Electron Micrographs: The Equivalence of Two Methods

1971 ◽  
Vol 29 ◽  
pp. 90-91 ◽  
Author(s):  
James A. Lake
Keyword(s):  
Fourier Transform ◽  
Fourier Transformation ◽  
Bacteriophage T4 ◽  
Three Dimensional ◽  
Degree Of Approximation ◽  
Dimensional Structure ◽  
Transmission Electron Micrograph ◽  
Mathematical Operation ◽  
Three Dimensional Structure ◽  
Inverse Fourier Transformation

A transmission electron micrograph is to a good degree of approximation a projection of a three dimensional structure. Provided that a sufficient number of projections are available, it is possible to reconstruct a three dimensional structure which is consistent with the projections. Among the methods which have been proposed for generating a three dimensional structure from projections, two methods alone produce single, unique structures which are consistent, in a least squares sense, with the projections from which they are derived.The first of these was demonstrated by DeRosier and Klug in a reconstruction of the tail of the bacteriophage T4. Their technique is illustrated in figure 1. A three dimensional structure, represented by the duck, is Fourier transformed to yield a three dimensional Fourier transform. (Fourier transformation is a mathematical operation readily performed on a digital computer.) An inverse Fourier transformation exists and the Fourier transform of the duck may be inversely transformed to recreate the three dimensional duck structure.

The Three-dimensional structure of frozen-hydrated nudaurelia capensis β virus

1987 ◽  
Vol 45 ◽  
pp. 650-651
Author(s):  
N. H. Olson ◽  
T. S. Baker ◽  
Wu Bo Mu ◽  
J. E. Johnson ◽  
D. A. Hendry
Keyword(s):  
South African ◽  
Rna Virus ◽  
Carbon Film ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Electron Dose ◽  
Total Electron ◽  
Three Dimensional Structure ◽  
Negative Stain ◽  
Dimensional Reconstruction

Nudaurelia capensis β virus (NβV) is an RNA virus of the South African Pine Emperor moth, Nudaurelia cytherea capensis (Lepidoptera: Saturniidae). The NβV capsid is a T = 4 icosahedron that contains 60T = 240 subunits of the coat protein (Mr = 61,000). A three-dimensional reconstruction of the NβV capsid was previously computed from visions embedded in negative stain suspended over holes in a carbon film. We have re-examined the three-dimensional structure of NβV, using cryo-microscopy to examine the native, unstained structure of the virion and to provide a initial phasing model for high-resolution x-ray crystallographic studiesNβV was purified and prepared for cryo-microscopy as described. Micrographs were recorded ∼1 - 2 μm underfocus at a magnification of 49,000X with a total electron dose of about 1800 e-/nm2.

Three Dimensional structure and organization of diploid chromosomes by optical section microscopy

1987 ◽  
Vol 45 ◽  
pp. 633-635
Author(s):  
David A. Agard ◽  
Yasushi Hiraoka ◽  
John W. Sedat
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Developmental State ◽  
Mitotic Cell ◽  
Biological Properties ◽  
Dimensional Structure ◽  
Specific Gene ◽  
Three Dimensional Structure ◽  
Complementary Techniques ◽  
Dynamic Structures

In an effort to understand the complex relationship between structure and biological function within the nucleus, we have embarked on a program to examine the three-dimensional structure and organization of Drosophila melanogaster embryonic chromosomes. Our overall goal is to determine how DNA and proteins are organized into complex and highly dynamic structures (chromosomes) and how these chromosomes are arranged in three dimensional space within the cell nucleus. Futher, we hope to be able to correlate structual data with such fundamental biological properties as stage in the mitotic cell cycle, developmental state and transcription at specific gene loci.Towards this end, we have been developing methodologies for the three-dimensional analysis of non-crystalline biological specimens using optical and electron microscopy. We feel that the combination of these two complementary techniques allows an unprecedented look at the structural organization of cellular components ranging in size from 100A to 100 microns.

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