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Vibrational microscopy

Fourier transform infrared microscopy. Vibrational Spectroscopy, 2002, 30, 147-156. [Pg.1868]

Clarke, R, Extracting process-related information from pharmaceutical dosage forms using near infrared microscopy. Vibrat. Spectrosc., 34 25-35 (2004). [Pg.611]

Stipe B C, Rezaei M A and Flo W 1998 Single-molecule vibrational spectroscopy and microscopy Science 280 1732... [Pg.319]

Microscopy methods based on nonlinear optical phenomena that provide chemical information are a recent development. Infrared snm-frequency microscopy has been demonstrated for LB films of arachidic acid, allowing for surface-specific imaging of the lateral distribution of a selected vibrational mode, the asymmetric methyl stretch [60]. The method is sensitive to the snrface distribntion of the functional gronp as well as to lateral variations in the gronp environmental and conformation. Second-harmonic generation (SHG) microscopy has also been demonstrated for both spread monolayers and LB films of dye molecules [61,62]. The method images the molecular density and orientation field with optical resolution, and local qnantitative information can be extracted. [Pg.67]

Fourier Transform (FT) Ranun spectroscopy (Model RFS 100/S, BRUKER Co.) using ND YAG laser was used to analyze the products on their structure electronic and vibration properties. The morphology of CNTs was observed by scanning dartron microscopy (SEM, Model S-4200, Hitach Co.) and transmission electron microscope (TEM, Modd JEOL 2000FX-ASID/EDS, Philips Co.). [Pg.750]

In our tip-enhanced near-field CARS microscopy, two mode-locked pulsed lasers (pulse duration 5ps, spectral width 4cm ) were used for excitation of CARS polarization [21]. The sample was a DNA network nanostructure of poly(dA-dT)-poly(dA-dT) [24]. The frequency difference of the two excitation lasers (cOi — CO2) was set at 1337 cm, corresponding to the ring stretching mode of diazole. After the on-resonant imaging, CO2 was changed such that the frequency difference corresponded to none of the Raman-active vibration of the sample ( off-resonant ). The CARS images at the on- and off- resonant frequencies are illustrated in Figure 2.8a and b, respectively. [Pg.29]

Knoll, B. and Keilmarm, F. (1999) Nearfield probing of vibrational absorption for chemical microscopy. Nature, 399, 134-137. [Pg.37]

Similarly, the first-order expansion of the p° and a of Eq. (5.1) is, respectively, responsible for IR absorption and Raman scattering. According to the parity, one can easily understand that selection mles for hyper-Raman scattering are rather similar to those for IR [17,18]. Moreover, some of the silent modes, which are IR- and Raman-inactive vibrational modes, can be allowed in hyper-Raman scattering because of the nonlinearity. Incidentally, hyper-Raman-active modes and Raman-active modes are mutually exclusive in centrosymmetric molecules. Similar to Raman spectroscopy, hyper-Raman spectroscopy is feasible by visible excitation. Therefore, hyper-Raman spectroscopy can, in principle, be used as an alternative for IR spectroscopy, especially in IR-opaque media such as an aqueous solution [103]. Moreover, its spatial resolution, caused by the diffraction limit, is expected to be much better than IR microscopy. [Pg.94]

Phospholipids, which are one of the main structural components of the membrane, are present primarily as bilayers, as shown by molecular spectroscopy, electron microscopy and membrane transport studies (see Section 6.4.4). Phospholipid mobility in the membrane is limited. Rotational and vibrational motion is very rapid (the amplitude of the vibration of the alkyl chains increases with increasing distance from the polar head). Lateral diffusion is also fast (in the direction parallel to the membrane surface). In contrast, transport of the phospholipid from one side of the membrane to the other (flip-flop) is very slow. These properties are typical for the liquid-crystal type of membranes, characterized chiefly by ordering along a single coordinate. When decreasing the temperature (passing the transition or Kraft point, characteristic for various phospholipids), the liquid-crystalline bilayer is converted into the crystalline (gel) structure, where movement in the plane is impossible. [Pg.449]

Stipe BC, Rezaei MA, Ho W (1998) Single-molecule vibrational spectroscopy and microscopy. Science 280(5370) 1732-1735... [Pg.31]

The present version of the book represents a completely revised update of the first edition as it appeared in 1993. Significant new developments in e.g. the scanning probe microscopies, imaging and vibrational techniques called for revision and additions to the respective chapters. But also the other chapters have been updated with recent examples, and references to relevant new literature. Many figures from the first version of the book have been improved to make them more informative. The chapter with case studies has been expanded with an example on polymerization catalysts. [Pg.11]

Forced-vibration instruments, 21 745 Force field calculations, 16 742 Force field energy, 16 742 Force field performance, 16 745 Force fields, 16 743-745 Force field simulations, 16 746-747 programs for, 16 746 Force modulation microscopy, 3 332 Forces, exponents of dimensions in absolute, gravitational, and engineering systems, 8 584t Forchlorfenuron, 13 43t, 53 Ford nuclear reactor, 17 594... [Pg.376]

We first experimented with the Quartz Crystal Microbalance (QCM) in order to measure the ablation rate in 1987 (12). The only technique used before was the stylus profilometer which revealed enough accuracy for etch rate of the order of 0.1 pm, but was unable to probe the region of the ablation threshold where the etch rate is expressed in a few A/pulse. Polymer surfaces are easily damaged by the probe tip and the meaning of these measurements are often questionable. Scanning electron microscopy (21) and more recently interferometry (22) were also used. The principle of the QCM was demonstrated in 1957 by Sauerbrey (22) and the technique was developed in thin film chemistiy. analytical and physical chemistry (24). The equipment used in this work is described in previous publications (25). When connected to an appropriate oscillating circuit, the basic vibration frequency (FQ) of the crystal is 5 MHz. When a film covers one of the electrodes, a negative shift <5F, proportional to its mass, is induced ... [Pg.413]

Ozensoy et al.127 also used PM-IRAS to study the CO adsorption behavior on Si02-supported Pd clusters. As mentioned above, these crystalline, ultrathin silica films possess the structural and electronic properties of the bulk analogues, but are thin enough to permit the use of vibrational and electronic spectroscopic techniques (and tunneling microscopy) without charging.39 40 As with the... [Pg.359]


See other pages where Vibrational microscopy is mentioned: [Pg.177]    [Pg.8788]    [Pg.177]    [Pg.8788]    [Pg.1214]    [Pg.1673]    [Pg.177]    [Pg.61]    [Pg.719]    [Pg.52]    [Pg.294]    [Pg.377]    [Pg.45]    [Pg.96]    [Pg.178]    [Pg.247]    [Pg.32]    [Pg.7]    [Pg.18]    [Pg.15]    [Pg.112]    [Pg.97]    [Pg.189]    [Pg.528]    [Pg.528]    [Pg.542]    [Pg.149]    [Pg.356]    [Pg.246]    [Pg.246]    [Pg.558]    [Pg.209]    [Pg.60]    [Pg.135]    [Pg.198]   
See also in sourсe #XX -- [ Pg.483 ]




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