Oxygen-17 and Silicon-29
2012-12 · NMR Basic Principles and Progress 17 knyga · Springer Science & Business Media
El. knyga
238
Puslapiai
reportĮvertinimai ir apžvalgos nepatvirtinti. Sužinokite daugiau
Apie šią el. knygą
Although it was shown very early [1] that the isotope 29Si is very valuable for NMR research, severe technical difficulties had to be overcome before silicon spectra could be recorded. This was due to the low sensitivity of the isotope resulting from its low gyro magnetic ratio, its low abundance and the rather long relaxation times. The introduction of the Fourier-Transform-Technique (FT-NMR) helped to surmount most of these problems, with the result, that more and more papers concerning silicon NMR appear. Thus, it seems now that most of the salient features of 29Si-NMR are known today. Some resume of the state of the art of 29Si_NMR have been reported [1-4]. Although the theory of 29Si-NMR is not yet understood beyond the basic features, it promises to be of value mainly for two reasons: 1. Silicon is strategically located in the Periodic Table of the elements between the elements carbon, aluminum and phosphorus. For an unified theory of chemical shifts and coupling constants of the heavier elements silicon NMR values will be important. 2. The normal coordination number of silicon is four. If the current view of the chemical shifts of the heavier elements is correct, then the paramagnetic part is dominant for the measured shift data. Two of the parameters used for the calcu lation of the paramagnetic part are bond orders and angles. Bond angles are rare ly determined experimentally with high precision.
Įvertinti šią el. knygą
Pasidalykite savo nuomone.
Skaitymo informacija
Išmanieji telefonai ir planšetiniai kompiuteriai
Įdiekite „Google Play“ knygų programą, skirtą „Android“ ir „iPad“ / „iPhone“. Ji automatiškai susinchronizuojama su paskyra ir jūs galite skaityti tiek prisijungę, tiek neprisijungę, kad ir kur būtumėte.
Nešiojamieji ir staliniai kompiuteriai
Galite klausyti garsinių knygų, įsigytų sistemoje „Google Play“ naudojant kompiuterio žiniatinklio naršyklę.
El. knygų skaitytuvai ir kiti įrenginiai
Jei norite skaityti el. skaitytuvuose, pvz., „Kobo eReader“, turite atsisiųsti failą ir perkelti jį į įrenginį. Kad perkeltumėte failus į palaikomus el. skaitytuvus, vadovaukitės išsamiomis pagalbos centro instrukcijomis.
