scholarly journals Indirect Electroreductive Cyclization of N-Allyl and N-Propargylamides Using a Nickel(II) Complex as an Electron-Transfer Catalyst: Selective Formation of Halogenated and Non-halogenated Pyrrolidinones.

1995 ◽  
Vol 43 (1) ◽  
pp. 32-36 ◽  
Author(s):  
Shigeko OZAKI ◽  
Hidenori MATSUSHITA ◽  
Miho EMOTO ◽  
Hidenobu OHMORI
Keyword(s):  
Electron Transfer ◽  
Selective Formation ◽  
Electroreductive Cyclization

Supramolecular Complexation of Porphyrin and Quinone with Two Coordination Bonds and Intramolecular Electron Transfer

1997 ◽  
Vol 01 (01) ◽  
pp. 55-66 ◽  
Author(s):  
HIROSHI IMAHORI ◽  
KOJI YAMADA ◽  
EIICHI YOSHIZAWA ◽  
KIYOSHI HAGIWARA ◽  
TADASHI OKADA ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Intramolecular Electron Transfer ◽  
Nmr Studies ◽  
Guest Molecules ◽  
H Nmr ◽  
Molecular Mechanics Calculation ◽  
Coordination Bonds ◽  
Supramolecular Complexation ◽  
Selective Formation ◽  
Porphyrin Dimer

V-shaped zinc porphyrin dimer and quinone with two pyridyl groups have been rationally designed and synthesized to assemble a porphyrin-quinone supramolecule with two coordination bonds. Selective formation of the 1:1 bridging structure between the host-guest molecules was seen by 1 H NMR and UV-Vis absorption spectroscopy. Molecular mechanics calculation suggests that the bridging structure has rigidity as well as flexibility in geometry between the redox pair, which supports the interpretation of 1 H NMR studies. Intramolecular photoinduced electron transfer from the excited singlet state of the porphyrin to the quinone was observed by steady-state fluorescence spectra and picosecond fluorescence lifetime measurements.

A light optical diffractometer for electron microscopical images operating in line

1978 ◽  
Vol 36 (1) ◽  
pp. 86-87
Author(s):  
P. Bonhomme ◽  
A. Beorchia
Keyword(s):  
Electron Microscopy ◽  
Electron Transfer ◽  
Electron Microscope ◽  
Image Converter ◽  
Coherent Light ◽  
Spatial Filters ◽  
Electron Image ◽  
Electron Microscopical ◽  
Working Parameters ◽  
Amorphous Part

We have already described (1.2.3) a device using a pockel's effect light valve as a microscopical electron image converter. This converter can be read out with incoherent or coherent light. In the last case we can set in line with the converter an optical diffractometer. Now, electron microscopy developments have pointed out different advantages of diffractometry. Indeed diffractogram of an image of a thin amorphous part of a specimen gives information about electron transfer function and a single look at a diffractogram informs on focus, drift, residual astigmatism, and after standardizing, on periods resolved (4.5.6). These informations are obvious from diffractogram but are usualy obtained from a micrograph, so that a correction of electron microscope parameters cannot be realized before recording the micrograph. Diffractometer allows also processing of images by setting spatial filters in diffractogram plane (7) or by reconstruction of Fraunhofer image (8). Using Electrotitus read out with coherent light and fitted to a diffractometer; all these possibilities may be realized in pseudoreal time, so that working parameters may be optimally adjusted before recording a micrograph or before processing an image.

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