Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 82 (1985), S. 4524-4536 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: An extension of the low-pressure infrared chemiluminescence technique has allowed the measurement of energy partitioning in the atom/radical reactions: F+NH2→HF+NH, F+ND2→DF+ND. A complete numerical model of the experiment is described in detail including its parametrization. This model allows the unambiguous determination of the primary energy distribution of the above reactions. These reactions give inverted product energy distributions, in contrast to the isoelectronic F+OH→HF+O reaction. The inverted primary energy distribution for F+NH2/ND2 indicates a direct abstraction mechanism. Ab initio quantum chemical computations on some features of the relevant potential energy surfaces support this direct abstraction route. An energetically accessible transition state, having approximately zero barrier, is found on the triplet surface which directly correlates reagents and products. The geometry of this triplet transition state is also suggestive of strong HF vibrational excitation. Abstraction on the triplet surface provides an alternative pathway to reaction on the lowest singlet surface, which contains a deep potential energy well corresponding to NH2F.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 5 (1993), S. 1269-1271 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: As a generalization of the classical Rayleigh–Ritz technique for self-adjoint systems, a variational method that appears capable of providing rapid estimates of the dispersion relation for complicated, non-self-adjoint linear stability operators is outlined. The method is illustrated by examining the linear stability of Taylor–Dean flow against general three-dimensional disturbances. Relatively simple trial functions provide surprisingly accurate estimates for the dispersion relation.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 88 (1984), S. 356-363 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Fluid Mechanics 35 (2003), S. 113-133 
    ISSN: 0066-4189
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract A review is given of the stability of complex fluids subject to homogeneous states of shearing, a research field that is scarcely two decades old. For the benefit of fluid mechanicians, a brief, somewhat historical overview is presented of material instability in elastoplastic solids, where one finds a considerable body of experiment and a rich source of theoretical concepts including Hadamard instability, strain localization, and nonlocal constitutive models. A survey is then given of recent theoretical and experimental studies of instability with shear banding in various complex fluids, including micellar solutions, particulate suspensions, and rapidly sheared granular media. Various stability analyses are encapsulated in a mathematical dynamical-systems model for constitutive equations of the rate-type, and a general linear-stability theory is given for viscoelastic fluids in unbounded homogeneous shear flows. A general form of (Kelvin) wave-vector stretching is shown to play a key role in the growth of Fourier modes, as illustrated by recent computations for granular shear flow. The Fourier description also provides an explicit representation of higher-gradient (nonlocal) effects as higher-order powers of wave number.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 89 (1985), S. 1825-1830 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Industrial & engineering chemistry research 27 (1988), S. 551-555 
    ISSN: 1520-5045
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 97 (1992), S. 1638-1648 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The A˜ 1A‘–X˜ 1A' band systems of HCOCN and DCOCN have been studied in depth using the technique of pyrolysis jet spectroscopy. Ab initio predictions of molecular structures and vibrational frequencies for the ground and excited state were made, to assist in the assignment of the vibronic structure in the laser-induced fluorescence (LIF) spectra. A resolved emission spectrum obtained by laser population of the 81 level of the excited state was analyzed to establish the ground state vibrational frequencies. Both the LIF and resolved emission spectra are consistent with a substantial elongation of the C=O bond on excitation, and smaller changes in the other geometric parameters. The excited state inertial defect, the pattern of bands involving the antisymmetric vibrations, and the ab initio predictions all suggest that the excited state structure is only slightly nonplanar. A rotational analysis of the 910 band of the DCOCN LIF spectrum has provided the first experimental rotational constants for the ground state of formyl cyanide-d1, which should be useful in attempts to observe the microwave spectrum. The uv spectrum of formyl cyanide is found to be remarkably similar to that of propynal.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 60-70 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Spectra of jet-cooled germanium dichloride were obtained by pyrolysis of trichlorogermane in the throat of a supersonic jet. Laser-induced emission excitation spectra were recorded for the weak 450–400 nm and strong 320–300 nm band systems, both of which were vibrationally analyzed. Ab initio predictions of the excited state geometries, vibrational frequencies, and excitation energies were made to aid in assigning the spectra. The strong ultraviolet band system is assigned as A˜ 1B1–X˜ 1A1 with upper state vibrational frequencies of ν1=354 cm−1 and ν2=104 cm−1. It is the direct analog of the 580–440 nm band system of dichlorocarbene. The weaker band system in the visible is shown to be the a˜ 3B1–X˜ 1A1 transition, with upper state vibrational frequencies of ν1=393 cm−1 and ν2=118 cm−1. This is the first report of direct laser-induced phosphorescence detection of the excited triplet state of any of the carbene or heavier carbene analogs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 5 (1993), S. 2295-2297 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The impulsive-source distribution or Green's function for an unbounded n-dimensional Euclidean space filled by a material medium which undergoes a time-dependent homogeneous deformation and which is characterized by a time-dependent anisotropic diffusion tensor is derived. The special case of time-independent velocity gradients is considered (motions with constant stretch history), in which the anisotropic diffusivity is assumed to arise from the distortion of the otherwise isotropic medium supporting the diffusion process. Explicit reductions are given for steady simple-shearing (viscometric) flows. Also, a brief discussion is given of the relevance to general linear Brownian dynamical systems and the associated Taylor dispersion processes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...