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  • 1
    Electronic Resource
    Electronic Resource
    Source localization of EEG versus MEG: Empirical comparison using visually evoked responses and theoretical considerations (1991)
    Springer
    Brain topography 4 (1991), S. 133-142 
    Details
    ISSN: 1573-6792
    Keywords: Visual EPs ; MEG ; Source localization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Theoretically, the information we can obtain about the functional localization of a source of brain activity from the scalp, for instance evoked by a sensory stimulus, is the same whether one uses EEG or MEG recordings. However, the nature of the sources and, especially of the volume conductor, poses constraints such that appreciable differences between both types of data may exist. We present here empirical and theoretical data that illustrate which are the main constraints and to what extent they may affect electric potential and magnetic field maps. The empirical data consists of visual evoked potential and magnetic fields to the appearance of a checkerboard pattern (half-visual field stimulation). The concept of equivalent dipole is presented and its limitations are discussed. It is considered that the concept of equivalent dipole (ED) yields only an approximate description of the activity of a patch of cortex. A main difference between EEG and MEG recordings is the fact that radially oriented dipoles can hardly be seen in the MEG in contrast with the EEG. Accordingly, a weak tangential dipole component is difficult to distinguish in the EEG if a strong radial component is also present. However, a combination of both methods can give useful complementary information in such cases. A factor that influences largely such differences is the model of volume conductor used. A four concentric spheres model, as commonly used for solving the inverse problem of source localization, causes appreciable errors when EEG data are used but much less in case of the MEG. The use of a model consisting of eccentric spheres fitting the four compartments, brain, CSF, skull and scalp, provides a better approximation of the real geometry of the head and allows to obtain comparable results for visual evoked potentials and magnetic fields. It is emphasized that for precise localization of EDs, especially based on EEG recordings, a realistic model of the different compartments of the head is necessary. The latter must be tailor made to a given subject using MRI-scans, in view of the large variability in head geometry between subjects.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01132770
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  • 2
    Electronic Resource
    Electronic Resource
    The influence of the volume conductor on electric source estimation (1993)
    Springer
    Brain topography 5 (1993), S. 337-345 
    Details
    ISSN: 1573-6792
    Keywords: MEG ; EEG ; Inverse solution ; Volume conduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01128687
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  • 3
    Electronic Resource
    Electronic Resource
    The estimation of a realistic localization of dipole layers within the brain based on functional (EEG, MEG) and structural (MRI) data: A preliminary note (1993)
    Springer
    Brain topography 5 (1993), S. 327-330 
    Details
    ISSN: 1573-6792
    Keywords: EEG ; MEG ; MRI ; Dipole Layers ; Functional localization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01128685
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  • 4
    Electronic Resource
    Electronic Resource
    Application of the Richardson extrapolation in simulation studies of EEGs (1987)
    Springer
    Medical & biological engineering & computing 25 (1987), S. 222-226 
    Details
    ISSN: 1741-0444
    Keywords: EEG ; Fredholm integral equation of the second kind ; MEG ; Multicompartment models ; Neumann equation ; Richardson extrapolation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02442855
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  • 5
    Electronic Resource
    Electronic Resource
    Controlling mechanism in the aqueous absorption of nitrogen oxides (1955)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 1 (1955), S. 105-111 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The reactions involved in the removal of nitrogen oxides from gases by reaction with water are reversible and proceed at a finite rate. It is possible therefore that the over-all process is controlled by the rate of the chemical reactions. On this basis an analysis of the process has been developed by the application of chemical kinetics, with consideration of reactions involving both nitrogen dioxide and dinitrogen tetroxide. The resulting differential equation has been simplified and integrated to give a final equation which can be tested experimentally.Theoretical methods are presented for predicting the extent of absorption of nitrogen oxides at various gas rates and concentrations and are compared with the experimental results.The paper presents some new concepts of the factors which control the rate of absorption of nitrogen dioxide and dinitrogen tetroxide in water. An understanding of the controlling factors in the process should indicate methods for improving the design of absorption towers in nitric acid plants and aid in the design of scrubbers for removing nitrogen oxides from waste gases.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690010116
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  • 6
    Electronic Resource
    Electronic Resource
    Simulation of particulate removal in gas-solid fluidized beds (1982)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 28 (1982), S. 39-49 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A mathematical model for simulating particulate removal in gas-solid fluidized beds is developed based on bubble assemblage concepts and particulate collection mechanisms. The importance of fluidization mechanics on the overall fluidized bed filtration performance is emphasized in the present study. Model predictions of fluidized bed filtration efficiencies are shown to compare favorably to the experimental results of various investigations. Because of the general formulation of the proposed model, it is believed to be applicable in the design of fluidized bed filtration operations.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690280107
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  • 7
    Electronic Resource
    Electronic Resource
    Processing MRI data for electromagnetic source imaging (1993)
    Springer
    Medical & biological engineering & computing 31 (1993), S. 600-606 
    Details
    ISSN: 1741-0444
    Keywords: EEG ; Image processing ; MEG ; MRI ; Segmentation ; Three-dimensional rendering
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Estimation of the source of activity in the brain from electro- and magneto-encephalographic measurements is becoming increasingly common. Structural information could assist in improving the calculation of the sources as well as providing the context of the source location. Magnetic resonance images are very useful for this purpose, but they still need to undergo various processing steps. The paper describes in details a practical method for full automatic processing of MRI images of a head, including segmentation of the images and triangulation of the surfaces.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02441808
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  • 8
    Electronic Resource
    Electronic Resource
    Ursachen, Bedeutung und Kontrolle der Stickstoff/Sauerstoff-Verbindungen in der LuftverunreinigungPlenarvortrag auf dem Jahrestreffen der Verfahrens-Ingenieure, 1. bis 3. Oktober 1968 in Stuttgart. (1969)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 41 (1969), S. 593-599 
    Details
    ISSN: 0009-286X
    Keywords: Chemistry ; Industrial Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Die Bedeutung der verschiedenen Arten der Stickoxide und ihr Beitrag zur Luftverunreinigung wird analysiert. Als Stickoxid-Quellen sind in dieser Hinsicht Kraftfahrzeuge von besonderer Bedeutung. Bei der Analyse der Methoden zur Verringerung des Stickoxid-Gehaltes von Abgasen wird der Entstehung von Stickstoff-Verbindungen in Verbrennungsmotoren und ihrer Verringerung durch direkte katalytische Reduktion besondere Aufmerksamkeit geschenkt. Zukünftig notwendige Forschungs- und Entwicklungsvorhaben werden behandelt, wobei neue, die Luft nicht verschmutzende Transportmittel für den Massenverkehr in die Betrachtungen mit einbezogen werden.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330411002
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  • 9
    Electronic Resource
    Electronic Resource
    Kristall- und Molekülstruktur von SbI3 · 9S3 (9S3 = 1,4,7-Trithiacyclononan) (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 727-730 
    Details
    ISSN: 0044-2313
    Keywords: Antimonytriiodide complex with trithiacyclononane ; synthesis ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal and Molecular Structure of SbI3 · 9S3 (9S3 = 1.4.7-Trithiacyclononane).SbI3 forms a 1:1 adduct with 1.4.7-trithiacyclononane. The crystal structure exhibits discrete complexes with a distorted octahedral coordination of antimony(III). In comparison with molecular SbI3 the Sb—I distances are elongated from 271.9 to 290.4 pm (mean). The mean value of the Sb—S distances is 287.5 pm. The planes through iodine and sulfur atoms, respectively, are nearly coplanar. There is no significant stereochemical influence of the Sb(III) lone pair.
    Notes: SbI3 bildet ein 1:1-Addukt mit 1,4,7-Trithiacyclononan. Die Kristallstruktur enthält diskrete Komplexe mit verzerrt oktaedrischer Koordination von Antimon(III). Im Vergleich zum molekularen SbI3 ist der Sb—I-Abstand von 271,9 auf 290,4 pm aufgeweitet. Der mittlere Sb—S-Abstand beträgt 287,5 pm. Die Ebenen durch die drei Iod- und drei Schwefelatome sind nahezu koplanar. Ein signifikanter stereochemischer Einfluß des nichtbindenden Elektronenpaares von Sb(III) ist nicht zu erkennen.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936190415
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  • 10
    Electronic Resource
    Electronic Resource
    Neutrale Thiolate und ein Iodidthiolat von Antimon(III). Die Kristallstrukturen von Sb(SC6H5)3, Sb(SC6H2Me3-2,4,6)3 und SbI(SC6H2Me3-2,4,6)2 (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 2119-2123 
    Details
    ISSN: 0044-2313
    Keywords: Antimony(III)-thiolates ; Antimony(III)-iodothiolate ; Crystal Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Neutral Thiolates and a Iodothiolate of Antimony(III). Crystal Structures of Sb(SC6H5)3, Sb(SC6H2Me3-2,4,6)3, and SbI(SC6H2Me3-2,4,6)2The crystal structures of Sb(SC6H5)3 (1), Sb(SC6 · H2Me3-2,4,6)3 (2), and the novel compound SbI(SC6H2Me3-2,4,6)2 (3) have been determined by X-ray crystallography. In addition to the expected trigonal pyramidal coordination of antimony intermolecular interactions are observed for 1 (Sb … O: 363.3 pm) and 3 (Sb … S: 2 × 369.4 pm) but not for 2. The reasons for these differences are discussed.
    Notes: Die Kristallstrukturen von Sb(SC6H5)3 (1), Sb(SC6H2Me3-2,4,6)3 (2) sowie der neuen Verbindung SbI(SC6H2Me3-2,4,6)2 (3) wurden mit Hilfe von Röntgenbeugungsmethoden bestimmt. Zusätzlich zu der erwarteten trigonal pyramidalen Umgebung von Antimon werden für 1 und 3, nicht jedoch für 2, intermolekulare Wechselwirkungen beobachtet (1: Sb … C: 363,3 pm; 3: Sb … S: 2 × 369,4 pm). Die Ursachen für diese Unterschiede werden diskutiert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19966221221
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