Download or read book PHTALOCYANINES ET NAPHTALOCYANINES RADICALAIRES written by MARCEL.. BOUVET and published by . This book was released on 1992 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: NOUS AVONS SYNTHETISE DES NAPHTALOCYANINES DE LUTECIUM: LA BISNAPHTALOCYANINE NPC#2LU, UN MELANGE DE PHTALO-NAPHTALOCYANINES PN#NNN#8##NLU (N4), ET LA PHTALO-NAPHTALOCYANINE DISSYMETRIQUE PCLUNPC. LES POTENTIELS D'OXYDO-REDUCTION DES PRODUITS ONT ETE MESURES. LA DIFFERENCE E ENTRE LES POTENTIELS DE PREMIERE OXYDATION ET DE PREMIERE REDUCTION DU MELANGE PN#NNN#8##NLU (N4) EST PLUS FAIBLE QUE POUR PC#2LU (0,37 CONTRE 0,48 V). PCLUNPC, PAR CONTRE, POSSEDE LES MEMES POTENTIELS QUE PC#2LU. LES CONDUCTIVITES ELECTRIQUES DE PN#NNN#8##NLU (N4) ET PCLUNPC SONT EGALES A 5.10##5 ##1 CM##1 (SOUS VIDE). LES ENERGIES D'ACTIVATION THERMIQUE VALENT RESPECTIVEMENT 0,38 ET 0,48 EV. LES FILMS PREPARES AVEC LA PHTALOCYANINE ET LA NAPHTALOCYANINE DE LITHIUM, PCLI ET NPCLI, POSSEDENT DES CONDUCTIVITES DE 2.10##6 ##1 CM##1, AVEC DES ENERGIES D'ACTIVATION EGALES A 0,9 ET 1,0 EV. TOUS CES COMPOSES, QUI SONT DES ESPECES RADICALAIRES, SONT DONC DES SEMI-CONDUCTEURS MOLECULAIRES. DANS UN SEMI-CONDUCTEUR CLASSIQUE LE NOMBRE DE PORTEURS DE CHARGE EST RELIE A L'ENERGIE D'ACTIVATION THERMIQUE DE LA CONDUCTIVITE PAR UNE LOI D'ARRHENIUS. POUR LES MATERIAUX MOLECULAIRES, LE MEME TYPE DE RELATION PEUT ETRE OBTENU A PARTIR DE L'EQUATION DE NERNST. NOUS AVONS MONTRE QUE E ETAIT EGAL A L'ENERGIE D'ACTIVATION THERMIQUE DE LA CONDUCTIVITE, ET AUSSI EGALE A L'ENERGIE DE LA BANDE DE TRANSFERT DE CHARGE INTERMOLECULAIRE. L'ETUDE DES FILMS PAR SPECTROSCOPIE DE PHOTOELECTRONS A PERMIS DE MONTRER QUE LA DIFFERENCE ENTRE LE NIVEAU DE FERMI ET LE DERNIER NIVEAU OCCUPE (E#F-E#V) ETAIT EGLAE A 1/2 (E#0#R#E#D-E#0#O#X). C'EST CE QUE NOUS ATTENDIONS POUR DES SEMI-CONDUCTEURS INTRINSEQUES. DANS LE CAS DE PC#2LU, LA PHASE TEXTUREE, QUI SE FORME DANS DES FILMS D'EPAISSEUR SUPERIEURE A 500 A, EST PLUS CONDUCTRICE QUE LA PHASE AMORPHE. LES FILMS DE PCLUNPC ET DE PN#NNN#8##NLU (N4) ETUDIES SONT EUX TOUJOURS AMORPHES

Download or read book Free Radical Induced DNA Damage and Its Repair written by Clemens Sonntag and published by Springer Science & Business Media. This book was released on 2006-03-20 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: The free-radical chemistry of DNA had been discussed in some detail in 1987 in my book The Chemical Basis of Radiation Biology. Obviously, the more recent developments and the concomitant higher level of understanding of mechanistic details are missing. Moreover, in the living cell, free-radical DNA damage is not only induced by ionizing radiation, but free-radical-induced DNA damage is a much more general phenomenon. It was, therefore, felt that it is now timely to review our present knowledge of free-radical-induced DNA damage induced by all conceivable free-radical-generating sources. Originally, it had been thought to include also a very important aspect, the repair of DNA damage by the cell’s various repair enzymes. Kevin Prise (Cancer Campaign, Gray Laboratory, L- don) was so kind to agree to write this part. However, an adequate description of this strongly expanding area would have exceeded the allocated space by much, and this section had to be omitted. The directors of the Max-Planck-Institut für Strahlenchemie (now MPI für Bioanorganische Chemie), Karl Wieghardt and Wolfgang Lubitz, kindly allowed me to continue to use its facilities after my retirement in 2001. Notably, our - brarian, Mrs. Jutta Theurich, and her right-hand help, Mrs. Rosemarie Schr- er, were most helpful in getting hold of the literature. I thank them very much. Without their constant help, this would have been very difficult indeed.