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  • 1
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Journal of Physics and Chemistry of Solids 46 (1985), S. 665-674 
    ISSN: 0022-3697
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Chemical Physics Letters 185 (1991), S. 393-398 
    ISSN: 0009-2614
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Journal of Molecular Structure 143 (1986), S. 305-308 
    ISSN: 0022-2860
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1573-482X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Laser-assisted processes are currently used in silicon technology. The response of the material to the laser beam depends strongly on its own physical properties and on the laser power density. The use of a microRaman system, allows the structural characteristics of the material to be analysed by varying the excitation laser power density on the sample over a large power range with a submicrometre lateral resolution. Results are reported on microindented crystalline silicon, showing that changes in the physical properties of the material, introducing grain boundaries, dislocations and cracking, result in a strong modification of the Raman spectrum. These spectral changes are enhanced for increasing laser power densities. Several mechanisms are pointed out as possible sources of the observed spectral modifications. These results show that Raman microprobe is a very promising technique for the diagnosis of technologically processed semiconductors and devices.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 24 (1993), S. 545-550 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The quantitative determination of crystallinites of polyethylene samples from the analysis of vibrational bands due to δ(CH2) twisting and v(CC) stretching in the Raman spectra between 950 and 1500 cm-1 was assessed. Several methods based on manual resolution of band envelopes and on computer-derived information using Gaussian and Lorentzian profiles were compared. The major source of error was found to be the estimation of the amorphous and crystalline interphase content, αb. A new method for the determination of sample crystallinity is proposed based on the time-dependent Fourier transform deconvolution of the spectral region between 950 and 1500 cm-1, which takes into account the baseline corrections and the influence of vibrational band shoulders in this region to obtain consistent values of αa, αb and αc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 25 (1994), S. 933-941 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A Raman spectroscopic study of aqueous solutions of MgSO4 as function of concentration and temperature was performed. From the analysis of the band profile of the internal vibrations of the sulphate ion, the spectroscopic ionic association constant was calculated at different temperatures. It was found that the association is solvent separated in the ranges of concentration and temperature studied. The large differences observed between the values obtained for the spectroscopic association constant and those obtained from macroscopic measurements were interpreted on the basis of a four-step solvent-separated dehydration mechanism. It is, assumed that the Raman spectra reflect only the short-distance force acting on the sulphate anions. The contribution of the long-range forces for the consecutive steps were calculated using the Bjerrum equation. Good agreement between the overall association constant thus calculated and the macroscopic value was found in the concentration and temperature ranges studied.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 25 (1994), S. 693-698 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A Raman spectroscopic study of aqueous solutions of sulphates with some mono- and divalent cations was performed. The dynamic properties of the sulphate ion were analysed in the wavenumber domain and in the time domain using Fourier transform methods. Special interest is devoted to those systems for which the ν1(SO42-) band shows an asymmetric profile. This asymmetry has been interpreted in two ways: (a) as arising from different S—O oscillators (associated and non-associated); their relative intensity is calculated using classical fitting methods, although the band parameters are obtained from a self-deconvolution method performed in the time domain; and (b) as arising from a perturbation of the water molecules in the vicinity of the sulphate ion. This perturbation is modelled in the time domain through a generalized correlation function. This latter represents a perturbed distribution of oscillators which undergo mutual interactions. These interactions are modelled by a feedback mechanism with two main parameters, the mutual coupling energy and the fraction of the distribution having mutual interaction. The correlation function thus modelled leads in the frequency domain to an asymmetric bandshape. The fitting of the experimental correlation function by this model gives essentially the same information as the fitting in the wavenumber domain for all the cases studied. Moreover, in the case of Li and Mg sulphates, both methods give the same value for the spectroscopically measured association enthalpy, 14 kJ mol-1 for Li and 21 kJ mol-1 for Mg.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 26 (1995), S. 663-668 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The Raman spectra of the v1(SO42-) band in aqueous solutions of Li2SO4, Na2SO4 and K2SO4 as a function of concentration at room temperature and for fixed concentrations in the temperature range 5 - 85°C were studied. It was found that the molar scattering coefficient for SO42- is virtually independent of the concentration and temperature in the studied range. Nevertheless, the v1(SO42) band shows some asymmetry on the high-wavenumber side for Li and Na and on the low-wavenumber side for K, which for these last two cases has not previously been reported. Moreover, the band position seems to be correlated with the sign and amount of the asymmetry as the concentration increases. On the other hand, temperature does not have a great effect on the band profile. In the case of Na and K, there is little narrowing of the band, whereas for Li there is slight broadening and an increase in the asymmetry. Quantitative analysis of these changes was performed using the vibrational correlation function. This was modelled considering the distribution of sulphate oscillators in the aqueous media as a convolution product of an unperturbed distribution by a perturbation function. This last function assumes a feedback mechanism in which the main parameters are the coupling energy and the fraction of the distribution having interactions. The dependence of these parameters and of the Gaussian and Lorentzian contributions to the band profile with concentration and temperature are discussed.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 20 (1989), S. 625-631 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A Raman spectroscopic study of aqueous solutions of KH2PO4 as a function of concentration and temperature has been made. Attention is focused on the analysis of the bands arising from the internal modes of the H2PO4- anions. The band profile of these internal modes has been analysed by a Fourier transform self-deconvolution method which allowed quantitative information about phosphate dimerization to be obtained. The results seem to indicate the existence of two different configurations for the dimers. The association constant for each dimer and their thermodynamic parameters were obtained from the spectroscopic data.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
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