Search NASA⌕ Search

SEARCH · Search NASA

Results for “SCANDIUM 59”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

2 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Nuclear Data Sheets for A=59☆

-- Abstract: Evaluated spectroscopic data and level schemes from radioactive decay and nuclear reaction studies are presented for {sup 59}Sc, {sup 59}Ti, {sup 59}V, {sup 59}Cr, {sup 59}Mn, {sup 59}Fe, {sup 59}Co, {sup 59}Ni, {sup 59}Cu, {sup 59}Zn, {sup 59}Ga, and {sup 59}Ge. This evaluation for A=59 supersedes the earlier one by C. M. Baglin (2002Ba42) and updates for some nuclides in the ENSDF database. Highlights: of this evaluation are the following: In {sup 59}Fe, a new level at 568.45 keV (3/2{sup −}) has been added. This resolves a doublet at 570 keV, which was reflected in earlier evaluations (1983An22, 1993Ba85, 2002Ba42) and literature as well. Conflicting spin assignments for 2153.62 keV level of {sup 59}Co [9/2,13/2 in (α,pγ); (13/2) in ({sup 15}N,4nγ); 15/2 in (p,p′γ), (7/2{sup −}) in (n,n′γ)] exist in the literature and additional experimental work is needed to resolve the issue.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Trivalent rare earth metal cofactors confer rapid NP-DNA polymerase activity

Here, a DNA polymerase with a single mutation and a divalent calcium cofactor catalyzes the synthesis of unnatural N3'→P5' phosphoramidate (NP) bonds to form NP-DNA. However, this template-directed phosphoryl transfer activity remains orders of magnitude slower than native phosphodiester synthesis. Here, we used time-resolved x-ray crystallography to show that NP-DNA synthesis proceeds with a single detectable calcium ion in the active site. Using insights from isotopic and elemental effects, we propose that one-metal-ion electrophilic substrate activation is inferior to the native two-metal-ion mechanism. We found that this deficiency in divalent activation could be ameliorated by trivalent rare earth and post–transition metal cations, substantially enhancing NP-DNA synthesis. Scandium(III), in particular, confers highly specific NP activity with kinetics enhanced by more than 100-fold over calcium(II), yielding NP-DNA strands up to 100 nucleotides in length.

59 BASIC BIOLOGICAL SCIENCES↗