Mapping microscopic electronic

Qualitative and quantitative elemental analysis and elemental maps inside electron microscope. With Be window detector Na —> U, with thin window detector C —> U analyzed. Detection limit 0.1%. 

Cytochrome C4 A Prototype for Microscopic Electronic Mapping of Multicenter Redox Metalloproteins... 

Examinations of the microstructure were carried out on an optical microscope Leica QWin and in the scanning electron microscope SEM XL30, Philips. In order to illustrate microstructures (the phase contrast and crystallographic orientation maps) backscattered electrons (BSE) and diffractions of them (EBSD) in SEM were used. For observations of surface morphology secondary electrons (SE) were used. 

Fig. 2. Consensus structure of the E. coli 70S ribosome and its subunits. A. B, C and D are different orientations of the large (SOS) subunit E, F, G and H are two orientations of the small (30S) subunit On the large subunit, E, M and P represent the nascent protein exit site, the membrane binding site, and the peptidyl transferase site, respectively. 23S 3 indicates the position of the 3 terminus of 23S rRNA. On the small subunit, IF-1,2,3 represents the probable location of initiation factors 1, 2 and 3. EF-Tu represents the binding site of the EF- Tu GTP aminoacyl-tRNA complex (see Protein biosynthesis). EF-G represents the binding site of elongation factor G (see Protein biosynthesis) near the interface area with the large subunit. 16S 3 and 16S 5 indicate the positions of the 3 and 5 termini of 16S rRNA. Numbers preceded by S and L represent ribosomal proteins of the small and large subunits, respectively, which have been mapped by electron microscopic visualization of subunit-antibody complexes. / is a diagrammatic representation of the whole ribosome, showing the probable location of mRNA and newly synthesized polypeptide, and the position and orientation of the ribosome with respect to the membrane of the endoplasmic reticulum during synthesis of secreted proteins.

That the description of electrons as waves is not simply a mathematical construct but is visibly real can be demonstrated by using a device called a scanning tunneling microscope (STM). This instrument allows the mapping of electron distributions in molecules at the atomic level. The picture shows an orbital image of tetracyanoethene deposited on a Ag surface, taken at 7 K. [Picture courtesy of Dr. Daniel Wegner, University of Munster, and Professor Michael F. Crommie, University of California at Berkeley]... 

If an incident electron beam of sufficient energy for AES is rastered over a surface in a manner similar to that in a scanning electron microscope (SEM), and if the analyzer is set to accept electrons of Auger energies characteristic of a particular element, then an elemental map or image is again obtained, similar to XPS for the Quantum 2000 (Sect. 2.1.2.5). 

IMS is a new, developing technique to visualize biomolecule maps in tissue. IMS has opened a new frontier in medicine as well as in clinical applications. Lipids and low-molecular-weight compounds in tissue sections cannot be observed with conventional microscopic or electron microscopic techniques therefore, no distribution map of these molecules in a tissue structure has been described in the scientific literature or in medical textbooks. However, IMS is bringing to light the characteristic distribution map of lipids (Fig. 21.11) this map made a major impact to lipid research. 

Various optical detection methods have been used to measure pH in vivo. Fluorescence ratio imaging microscopy using an inverted microscope was used to determine intracellular pH in tumor cells [5], NMR spectroscopy was used to continuously monitor temperature-induced pH changes in fish to study the role of intracellular pH in the maintenance of protein function [27], Additionally, NMR spectroscopy was used to map in-vivo extracellular pH in rat brain gliomas [3], Electron spin resonance (ESR), which is operated at a lower resonance, has been adapted for in-vivo pH measurements because it provides a sufficient RF penetration for deep body organs [28], The non-destructive determination of tissue pH using near-infrared diffuse reflectance spectroscopy (NIRS) has been employed for pH measurements in the muscle during... 

From the above discussion, we can see that the purpose of this paper is to present a microscopic model that can analyze the absorption spectra, describe internal conversion, photoinduced ET, and energy transfer in the ps and sub-ps range, and construct the fs time-resolved profiles or spectra, as well as other fs time-resolved experiments. We shall show that in the sub-ps range, the system is best described by the Hamiltonian with various electronic interactions, because when the timescale is ultrashort, all the rate constants lose their meaning. Needless to say, the microscopic approach presented in this paper can be used for other ultrafast phenomena of complicated systems. In particular, we will show how one can prepare a vibronic model based on the adiabatic approximation and show how the spectroscopic properties are mapped onto the resulting model Hamiltonian. We will also show how the resulting model Hamiltonian can be used, with time-resolved spectroscopic data, to obtain internal... 

However, its was found possible to infer all four microscopic tensor coefficients from macroscopic crystalline values and this impossibility could be related to the molecular unit anisotropy. It can be shown that the molecular unit anisotropy imposes structural relations between coefficients of macroscopic nonlinearities, in addition to the usual relations resulting from crystal symmetry. Such additional relations appear for crystal point group 2,ra and 3. For the monoclinic point group 2, this relation has been tested in the case of MAP crystals, and excellent agreement has been found, triten taking into account crystal structure data (24), and nonlinear optical measurements on single crystal (19). This approach has been extended to the electrooptic tensor (4) and should lead to similar relations, trtten the electrooptic effect is primarily of electronic origin. 

Fig. 10. X-ray elemental map in the electron microscope of metal-substituted aluminophosphate (MAPO-36 (with M = Zn)) catalyst. The map shows a uniform distribution of the elements in the sample.

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