ESEMs

Electron Spin Resonance Spectroscopy. Several ESR studies have been reported for adsorption systems [85-90]. ESR signals are strong enough to allow the detection of quite small amounts of unpaired electrons, and the shape of the signal can, in the case of adsorbed transition metal ions, give an indication of the geometry of the adsorption site. Ref. 91 provides a contemporary example of the use of ESR and of electron spin echo modulation (ESEM) to locate the environment of Cu(II) relative to in a microporous aluminophosphate molecular sieve. 

ESEM environmental scanning electron microscope ESI electron spectroscopic imaging... 

As a special development in recent years, SEMs have been designed which no longer necessitate high vacuum (enviromnental SEM, ESEM variable pressure SEM, VPSEM). This development is important for the imaging of samples with a residual vapour pressure, such as aqueous biological or medical samples, but also samples in materials science (wet rock) or organic chemistry (polymers). 

Paola, D. et al.. Characterization of the anthocyanin fraction of Sicilian hlood orange juice hy micro-HPLC-ESEMS, J. Agric. Food Chem., 51, 1173, 2003. 

PyFT-IR", CuPyMS", GC-FTIR, LD, FTICR, PDMS, LMMS", SSIMS", PDA, SEM", STEM", ESEM, PIXE... 

ECD (1) Electron-capture detector (2) Electrochemical detector E-SEM, ESEM Environmental scanning electron microscopy... 

Figure 11 Raman (left) and ESEM (right, SE and BSE) images (for explanation see text). (See Color Plate Section at the end of this book.)...

SEM was carried out using an FEI QUANTA ESEM. AFM was carried out using a JPK NanoWizard in contact mode. 

FIGURE 4.14 Schematic cross-section of the platform for in-vitro intracellular recording of ion concentration, designed for hepatocyte cell culture (a) and ESEM pictures of a micropipette (tilted at 75°) filled with the membrane cocktail. (From [102].)... 

Instrumentation, image formation, accessories, and applications of conventional scanning electron microscopy will be discussed. Information about the ESEM will also be presented. 

Following early ETEM investigations using environmental cells, environmental scanning electron microscopy (ESEM) has been developed for characterization of surface effects of bulk SEM samples in the presence of gaseous or wet environments (111-114). The method has been applied to the examination of food, wool fibers (111), and polymers (112) and in the conservation of cultural properties (113). Recently, fuel cell catalysts have been characterized using a low-voltage ESEM with a resolution capability of 2 nm (114). 

Information on the nature of the chemical environment of trace metal Ions adsorbed on clay minerals can be obtained by a number of spectroscopic methods, but the principal applications have used either XPS or ESR spectroscopy, or one of its related techniques, such as ENDOR and ESEM spectroscopy. 

ESR and ESEM studies of Cu(II) in a series of alkali metal ion-exchanged Tl-X zeolites were able to demonstrate the influence of mixed co-cations on the coordination and location of Cu(II) (60). The presence of Tl(l) forces of Cu(II) into the -cage to form a hexaaqua species, whereas Na and K result in the formation of triaqua or monoaqua species. In NaTl-X zeolite, both species are present with the same intensity, indicating that both cations can influence the location and coordination geometry of Cu(II). The Cu(II) species observed after dehydration of Tl-rich NaTl-X and KT1-X zeolites was able to interact with ethanol and DMSO adsorbates but no such interaction was observed with CsTl-X zeolites. This interaction with polar adsorbates was interpreted in terms of migrations of the copper from the -cages. 

ESEM results on the interaction of silica-exchanged Cu(II) with a range of adsorbates showed that one or two adsorbate molecules were able to coordinate to the Cu depending on the chemical interaction, polarity and size (7[2). Differences in A, were observed for N- and O-coordinated ligands, but these seem to reflect a change in coordination symmetry and not a difference in adsorbate ligand number. N-coordinated ligands form approximately square planar... 

Rosenqvist, M. (2000). The distribution of introduced acetyl groups and a bnseed oil model substance in wood examined by microradiography and ESEM. International Research Group on Wood Preservation, Doc. No. IRG/WP 00-40169. 

Alonso J, Angermeyer MC, Bernert S, et al (2004) Prevalence of mental disorders in Europe results from the European Study of the Epidemiology of Mental Disorders (ESEMeD) project. Acta Psychiatr Scand Suppl 420 21-27 Andrade L, Caraveo-Anduaga JJ, Berglund P, Bijl R, Kessler RC, Dernier O, Walters E, Kylyc C, Offord D, Ustun TB, Wittchen H-U (2000) Cross-national comparisons of the prevalences and correlates of mental disorders. Bull World Health Organ 78 413-426... 

N. Schrage, J. Becker, White precipitation after FeHe endotamponade. ESEM and EDXA analysis. Presented at the First Meeting on Heavy Tamponades, Telfs, (2003). 

ESEM (Danilotos 1990, 1997) is being used for in situ studies of polymers to understand a variety of surface effects in the presence of water such as swelling... 

In related work, Dong and coworkers reported using the hydrophobic IL [C4CiIm][PFg] mixed with MWCNs to form two types of MEs [35,36]. In one report, MWCNs were mixed with [C4CiIm][PFJ and applied to a GC electrode [35]. Environmental scanning electron microscopy (ESEM) images of the films showed homogeneously dispersed island-like particles that open up into a number of rope-like 3-D networks. They incorporated GOx into... 

Figure 19 Schematic representation of [VO(H20) +] and average intemuclear distances (A) from electron spin echo modulation (ESEM), electron nuclear double resonance (ENDOR) and X-ray diffraction studies4 ...

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