Search results for "DOF"
showing 4 items of 84 documents
Cubic and Spirocyclic Radicals Containing a Tetraimidophosphate Dianion [P(NR)3(NR‘)]•2-
2005
The reaction of Cl3PNSiMe3 with 3 equiv of LiHNR (R = iPr, Cy, tBu, Ad) in diethyl ether produces the corresponding tris(amino)(imino)phosphoranes (RNH)3PNSiMe3 (1a, R = iPr; 1b, R = Cy; 1c, R = tBu; 1d, R = Ad); subsequent reactions of 1b−d with nBuLi yield the trilithiated tetraimidophosphates {Li3[P(NR)3(NSiMe3)]} (2a, R = Cy; 2b, R = tBu; 2c, R = Ad). The reaction of [(tBuNH)4P]Cl with 1 equiv of nBuLi results in the isolation of (tBuNH)3PNtBu (1e); treatment of 1e with additional nBuLi generates the symmetrical tetraimidophosphate {Li3[P(NtBu)4]} (2d). Compounds 1 and 2 have been characterized by multinuclear (1H, 13C, and 31P) NMR spectroscopy; X-ray structures of 1b,c were also obtai…
Il Microbiota delle piante, ovvero le piante hanno bisogno dei microrganismi
2017
Le relazioni tra le piante e i fattori ambientali (il clima, i nutrienti, l’acqua, la composizione del suolo, etc) sono da tempo ampiamente studiate. Resta invece ancora molto da capire sul ruolo che la componente biologica del suolo (ci sono oltre cento milioni di cellule microbiche in un grammo di suolo!) ha sullo sviluppo e la salute delle piante. Nella rizosfera soprattutto (la porzione di suolo influenzata dalla presenza di radici), gli essudati radicali favoriscono lo sviluppo di microrganismi (batteri, funghi, protozoi, virus) che interagiscono con le radici e con il suolo nell’influenzare i processi di trasformazione ed assorbimento dei nutrienti, la crescita della pianta e le infez…
Mūžzaļo rododendru vienpumpura spraudeņu ar lapu rizoģenēze no rododendru saknēm izolētu endofītisko sēņu Mortierella sp. un Calcarisporium arbuscula…
2016
Tā kā Latvijā un citviet pasaulē rododendrus plaši izmanto visa veida apstādījumos – gan pilsētu parkos, gan arī piemājas teritorijās, ir svarīgi tos pavairot iespējami īsākā laikā un iegūt kvalitatīvus jaunos augus. Visplašāk tiek izmantotas veģetatīvās pavairošanas metodes, jo šķirnēm ir būtiski saglabāt to ģenētisko materiālu. Ir novērota atsevišķu endofītisko sēņu pozitīvā ietekme uz apsakņošanās procesu, taču trūkst informācijas par endofītisko sēņu ietekmi uz rizoģenēzes procesu, pavairojot augus ar klasiskajām pavairošanas metodēm. Darba mērķis ir noskaidrot, kā no mūžzaļo rododendru šķirnes ‘Babītes Lavanda’ saknēm izolētās endofītiskās sēnes Calcarisporium arbuscula un Mortierella …
Synthesis and Structures of Aluminum and Magnesium Complexes of Tetraimidophosphates and Trisamidothiophosphates: EPR and DFT Investigations of the P…
2005
Reactions of (RNH)3PNSiMe3 (3a, R = tBu; 3b, R = Cy) with trimethylaluminum result in the formation of {Me2Al(μ-NtBu)(μ-NSiMe3)P(NHtBu)2]} (4) and the dimeric trisimidometaphosphate {Me2Al[(μ-NCy)(μ-NSiMe3)P(μ-NCy)2P(μ-NCy)(μ-NSiMe3)]AlMe2} (5a), respectively. The reaction of SP(NHtBu)3 (2a) with 1 or 2 equiv of AlMe3 yields {Me2Al[(μ-S)(μ-NtBu)P(NHtBu)2]} (7) and {Me2Al[(μ-S)(μ-NtBu)P(μ-NHtBu)(μ-NtBu)]AlMe2} (8), respectively. Metalation of 4 with nBuLi produces the heterobimetallic species {Me2Al[(μ-NtBu)(μ-NSiMe3)P(μ-NHtBu)(μ-NtBu)]Li(THF)2} (9a) and {[Me2Al][Li]2[P(NtBu)3(NSiMe3)]} (10) sequentially; in THF solutions, solvation of 10 yields an ion pair containing a spirocyclic tetraimid…