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  • 1
    Electronic Resource
    Electronic Resource
    Photodissociation spectroscopy of Zn+(C2H4) (2001)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 115 (2001), S. 5823-5829 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have investigated the spectroscopy and photochemistry of Zn+(C2H4) in an angular reflectron time-of-flight mass spectrometer. We identify four absorption bands in the spectral range 220–550 nm. These bands are assigned to radiative transitions in the bimolecular complex correlating with Zn-centered and ethylene-centered absorptions, and with Zn–ethylene photo-induced charge transfer processes. The lowest energy band, assigned as 1 2B2←1 2A1, is a weak continuum consistent with a large geometry change and fast predissociation. The higher energy 1 2B1←1 2A1 band shows a long progression in the intermolecular stretch with a mode frequency of ωe=333.7 cm−1. The spectroscopic results, including partially resolved rotational structure, are consistent with a weakly bound, π-bonded complex in C2v symmetry. A Birge–Sponer analysis gave an estimate for the dissociation energies of the excited 1 2B1 state as De′=2.76 eV and the ground 1 2A1 state as De″=0.86 eV. A second structured band at still higher energies is tentatively assigned as 2 2B2←1 2A1 and shows activation of higher frequency intramolecular ethylene modes. Zn+ and C2H4+ fragment ions are observed over most of the spectral range. At higher energies (λ〈250 nm) we also see a significant branching to reactive products C2H2+ and C2H3+ that result from charge transfer accompanied by C–H bond cleavage. We propose a reaction mechanism that involves coupling through an excited charge-transfer state followed by C–H bond insertion. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1399299
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  • 2
    Electronic Resource
    Electronic Resource
    Photodissociation spectroscopy of Al+-acetaldehyde (2002)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 116 (2002), S. 4847-4852 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have investigated the photodissociation spectroscopy of the Al+-acetaldehyde bimolecular complex over the spectral range 212–345 nm. We find evidence for three overlapping molecular absorption bands in the near UV. Two of the bands are unstructured and are assigned as 1A″ and 2A″←1A′. These continuum bands are of mixed character with contributions from Al+-centered 3pπ(A″)←3sσ(A′), acetaldehyde-centered π*(A″)←n(A′), and Al-acetaldehyde charge transfer excitation processes. The third absorption band at short wavelengths, λ〉223 nm, shows a prominent vibrational progression with a mode frequency ωe=210±4 cm−1. The structured band is assigned as 2A′←1A′ and correlates to an Al+-centered 3pπ(A′)←3sσ(A′) radiative transition; the vibrational progression is assigned to the intermolecular Al+-acetaldehyde in-plane bend. Spectroscopic results are in good agreement with ab initio predictions. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1452729
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  • 3
    Electronic Resource
    Electronic Resource
    Photodissociation spectroscopy of Mg+–acetaldehyde (2001)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 114 (2001), S. 10288-10293 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have investigated the photodissociation spectroscopy of the Mg+–acetaldehyde bimolecular complex over the spectral range 220–400 nm. We find evidence for four distinct absorption bands in the near ultraviolet that correlate with Mg+-based and acetaldehyde-based transitions. Our results suggest that the Mg+-centered 3pπ(A″)←3sσ(A′) and acetaldehyde-centered π*(A″)←n(A′) transitions are mixed, and result in significant vibrational excitation in the complex leading to broad and unresolved absorption bands. In contrast, the predominantly Mg+-based excitation bands, assigned as 3pπ(A′)←3sσ(A′) and 3pσ(A′)←3sσ(A′), each show prominent vibrational progressions identified with intermolecular wagging modes of the complex. These intermolecular wag progressions are short and anharmonic indicating low barriers to isomerization. In the 3pσ(A′)←3sσ(A′) band several higher frequency vibrational modes are also active and have been assigned to the Mg–OCHCH3 intermolecular stretch, a CCO deformation mode, and the C–O stretch. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1374579
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  • 4
    Electronic Resource
    Electronic Resource
    A novel application of gas-diffusion electrodes as electrochemical gas sensors
    Amsterdam : Elsevier
    Journal of Electroanalytical Chemistry 248 (1988), S. 69-75 
    Details
    ISSN: 0022-0728
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0022-0728(88)85151-9
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  • 5
    Electronic Resource
    Electronic Resource
    Recruitment of functional GABA A receptors to postsynaptic domains by insulin (1997)
    [s.l.] : Macmillan Magazines Ltd.
    Nature 388 (1997), S. 686-690 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Modification of synaptic strength in the mammalian central nervous system (CNS) occurs at both pre- and postsynaptic sites,. However, because postsynaptic receptors are likely to be saturated by released transmitter, an increase in the number of active postsynaptic receptors may be a more ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/388686a0
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  • 6
    Electronic Resource
    Electronic Resource
    Towards an acoustoelastic theory for measurement of residual stress (1987)
    Springer
    Journal of elasticity 17 (1987), S. 159-182 
    Details
    ISSN: 1573-2681
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The rudiments of an acoustoelastic theory is developed within the framework of linear elasticity with initial stress. Since no assumption is made about the origin of the initial stress, our acoustoelastic theory will be applicable to evaluation of stress in plastically deformed bodies, provided that the superimposed ultrasonic waves be hyperelastic. New universal relations are deduced. An approach to evaluation of stress which does not use calibration specimens and makes full use of universal relations in our acoustoelastic theory is advocated. Examples are given which illustrate application of our theory to evaluate residual stress in plates. Preliminary corroborations of our theory are provided by the recent experiments of King & Fortunko and Thompson et al.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00043022
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  • 7
    Electronic Resource
    Electronic Resource
    A thought-experiment concerning an endochronic-type theory (1983)
    Springer
    Acta mechanica 48 (1983), S. 103-110 
    Details
    ISSN: 1619-6937
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01178501
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  • 8
    Electronic Resource
    Electronic Resource
    Elastic-plastic analysis of a flat ring subject to internal pressure (1977)
    Springer
    Acta mechanica 27 (1977), S. 155-172 
    Details
    ISSN: 1619-6937
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Für die Spannungen in einem flachen Ring, durch Druck belastet, wird eine exakte elastisch-plastische Lösung auf der Grundlage derJ 2 Deformationstheorie in Verbindung mit einem modifizierten Ramberg-Osgood-Gesetz erhalten. Die Ergebnisse werden auf der Basis des Kriteriums von Budiansky, für die Anwendbarkeit derJ 2 Deformationstheorie bewertet. Durch Verwendung exakter elastisch-plastischer Spannungen wird die radiale Aufweitung und die permanente Zunahme der Ringdicke am inneren Rand erhalten. Nach Wegnahme des Druckes werden Restspannungen am inneren Rand produziert.
    Notes: Summary An exact elastic-plastic solution for the stresses in a flat ring subject to pressure is obtained on the basis ofJ 2 deformation theory together with a modified Ramberg-Osgood law. The results are assessed on the basis of Budiansky's criterion for the acceptability ofJ 2 deformation theory. By using exact elastic-plastic stresses, the radial enlargement and the permanent increase in thickness of the ring at the hole are obtained. Upon release of the pressure, residual stresses are produced around the hole.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01180083
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  • 9
    Electronic Resource
    Electronic Resource
    A two-surface plasticity theory and its application to multiaxial loading (1987)
    Springer
    Acta mechanica 69 (1987), S. 43-57 
    Details
    ISSN: 1619-6937
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary A two-surface theory based upon experimental results is presented. The theory utilizes the concept of a yield surface and a loading surface to describe the essential features of the time-independent inelastic behavior of materials. The theory is implemented in a computer program and its predictions are compared to a variety of axial-torsional experimental data including both proportional and nonproportional loading.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01175713
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  • 10
    Electronic Resource
    Electronic Resource
    Measurement of stress based upon universal relations in acoustoelasticity (1989)
    Springer
    Experimental mechanics 29 (1989), S. 109-114 
    Details
    ISSN: 1741-2765
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A new approach to ultrasonic measurement of stress was proposed recently by Man and Lu. That approach is based on universal relations that result from material symmetry in an acoustoelastic theory applicable to plastically deformed bodies for which superimposed ultrasonic waves can be taken as elastic. When applicable, the Man-Lu approach circumvents the two main difficulties of the acoustic-birefringence method, namely those of unknown initial texture and plastic deformation. An experiment was performed to verify a new universal relation derived by Man and Lu in their earlier work. Plastic strain was developed during the test. The results were in basic accord with the prediction of the theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02321361
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