Space-resolved

Pulsed spark sources, in which the material to be analyzed is part of one electrode, are used for semiquantitative analyses. The numerous and complex processes involved in spark discharges have been studied in detail by time- and space-resolved spectroscopy (94). The temperature of d-c arcs, into which the analyte is introduced as an aerosol in a flowing carrier gas, eg, argon, is approximately 10,000 K. Numerous experimental and theoretical studies of stabilized plasma arcs are available (79,95). 

Figure 6. Scheme of microwave-electrochemical setup showing time-resolved, space-resolved and potential-dependent measurement techniques, as well as combinations of these. 

Figure 7 shows an example of a space-resolved microwave conductivity measurement of the semiconducting surface of a natural pyrite (FeS2) sample (from Murgul, Turkey). The overflow of the PMC signal (white color) was adjusted to a level that shows the patterns of distribution of low photoeffects (dark areas). Figure 8 shows a similar image in which,... 

Figure 7. Example of space-resolved photoinduced microwave conductivity mapping of semiconductor interface distribution of photoconductivity in natural pyrite (from Murgul, Turkey, surface etched in acid solution). The overflow was adjusted to show patterns of low photoactivity. For color version please see color plates opposite p. 452.

Preliminary measurements with space-resolved PMC techniques have shown that PMC images can be obtained from nanostructured dye sensitization cells. They showed a chaotic distribution of PMC intensities that indicate that local inhomogeneities in the preparation of the nanostructured layer affect photoinduced electron injection. A comparison of photocurrent maps taken at different electrode potentials with corresponding PMC maps promises new insight into the function of this unconventional solar cell type. 

Matsui, Y., Kamimoto, T., and Matsuoka, S., A Study on the Time and Space Resolved Measurement of Flame Temperature and Soot Concentration in a D.I. Diesel Engine by the Two-Color Method, SAE, 790491,1974. 

Dendrimers with a polyphenyl core around a central biphenyl unit decorated at the rim with peryleneimide chromophores have been investigated both in bulk and at the single-molecule level in order to understand their time and space-resolved behavior [28]. The results obtained have shown that the conformational distribution plays an important role in the dynamics of the photophysical processes. Energy transfer in a series of shape-persistent polyphenylene dendrimers substituted with peryleneimide and terryleneimide chro-mophoric units (4-7) has been investigated in toluene solution [29]. 

S. D. Beyea, B. J. Balcom, T. W. Bremn-er, R. L. Armstrong, P. E. Grattan-Bellew 2003, (Detection of microcracking in cementious materials with space resolved 1H nuclear magnetic resonance relaxometry), J. Am. Ceram. Soc. 86 (5), 800-805. 

Summary. This Chapter focuses on the investigation of fast electron transport studies in solids irradiated at relativistic laser intensities. Experimental techniques based upon space-resolved spectroscopy are presented in view of their application to both ultrashort Ka X-ray sources and fast ignition studies. Spectroscopy based upon single-photon detection is unveiled as a complementary diagnostic technique, alternative to well established techniques based upon bent crystals. Application of this technique to the study of X-ray fluorescence emission from fast electron propagation in multilayer targets is reported and explored as an example case. 

In space-resolved immunoassays, a smooth metal slide is coated with an antibody monolayer, and a parallel laser beam is used to quantitate surface bound fluorophore.1(37,38) Scattered light is low since the excitation is reflected into a different space, although scatter still remains the principal source of background. 

W. K Wang, L. T. Ho, and Y. Chiang, Space-resolved fluoroimmunoassay for quantifying os-fetoprotein in serum, Clin. Chem. 39, 1659-1661 (1993). 

Huang, Y. S., Karashkna, T., Yamamoto, M., and Hamaguchi, H. 2006. Molecular-level investigation of the structure, transformation, and bioactivity of single living flssion yeast cells by time- and space-resolved Raman spectroscopy. Biochemistry. 44 10009-19. 

Figure 50. Snapshots of oxygen incorporation experiments in Fe-doped SrTi03, recorded by in situ time and space resolved optical absorption spectroscopy.256 Rhs column refers to the corresponding oxygen concentration profiles, in a normalized representation. Top row refers a predominantly diffusion controlled case (single crystal), center row to a predominandy surface reaction controlled case (single crystal), bottom row to transport across depletion layers at a bicrystal interface.257,258 For more details on temperature, partial pressure, doping content, structure see Part I and Ref.257-259 Reprinted from J. Maier, Solid State Ionics, 135 (2000) 575-588. Copyright 2000 with permission from Elsevier.

Time- and space-resolved fluctuation data for flame gas temperature and major species densities have been obtained from Raman scattering and from stronger inelastic scattering processes. When combined with information about velocity from laser velocimetry, these data and their correlations provide key new information for flow field and combustion field modeling. 

Time- and space-resolved major component concentrations and temperature in a turbulent gas flow can be obtained by observation of Raman scattering from the gas. (1, 2) However, a continuous record of the fluctuations of these quantities is available only in those most favorable cases wherein high Raman scattering rate and/or slow rate of time variation of the gas allow many scattered photons (> 100) to be detected during a time resolution period which is sufficiently short to resolve the turbulent fluctuations. (2, 3 ) Fortunately, in other cases, time-resolved information still can be obtained in the forms of spectral densities, autocorrelation functions and probability density functions. (4 5j... 

The interaction of an ultrahigh-intensity laser with a dense plasma is of wide interest, as these lasers open up new horizons for research, such as fs X-ray radiation probing [1,2], energetic particle acceleration [3], and inertial confinement fusion [4,5]. A new spectroscopic method that provides the kind of time- and space-resolved information required to obtain a more quantitative understanding of energy deposition than that provided by particle measurements has been under development [5-8]. Because of the relatively low temperatures that can be accessed with current lasers, conventional K-shell line spectroscopy using near-fully ionized plasma is not suitable. 

A method to assay all phosphorous-containing metabolites at once is 31P-NMR spectroscopy (see the chapter by Sonnleitner in this volume - the section on NMR), the main limitation being the sensitivity for the very low-concentrated metabolites. NMR should be, in principle, also suitable for obtaining space-resolved (imaging) information [42], however, the technical difficulties have yet to be solved. 

Urakawa A, Baiker A. Space-resolved profiling relevant in heterogeneous catalysis. Top Catal. 2009 52 1312. 

M. Pauchard, S. Huber, R. Meallet-Renault, H. Maas, R. Pansu, and G. Calzaferri, Time- and Space-resolved Luminescence of a Photonic Dye-zeolite Antenna. Angew. Chem., Int. Ed., 2001, 40, 2839-2842. 

Figure 12.13 illustrates a versatile experimental set-up for microwave conductivity measurements with the microwave source (8 0 GHz), a circulator and a detector, which monitors the microwave energy reflected from the electrochemical or photovoltaic cell. The cell and electrode geometries are designed in such a way that the microwave power can reach the energy-converting interface (losses in metal contacts or aqueous electrolyte should be minimised). Depending on the experimental conditions, time-resolved, space-resolved or potential-dependent measurements are possible as well as combinations (for further details, see Schlichthbrl and Tributsch, 1992 Wiinsch et al., 1996 Chaparro and Tributsch, 1997 Tributsch, 1999). 

These techniques monitor the macroscopic changes of size or weight. They do not allow a discussion of the microscopic processes during swelling, the shape of the diffusion profile as well as the location and concentration of the diffusing liquid. All this information is available and can be visualized time- and space-resolved by imaging techniques, e.g., NMR imaging see Sect. 3.2. 

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