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Abstract We study the solar cycle dependence of various turbulence cascade rates based on the methodology developed by Adhikari et al. that utilizes Kolmogorov phenomenology. This approach is extended to derive the heating rates for an Iroshnikov–Kriachnan (IK) phenomenology. The observed turbulence cascade rates corresponding to the total turbulence energy, fluctuating magnetic energy density, fluctuating kinetic energy, and the normalized cross helicity are derived from WIND spacecraft plasma and magnetometer data from 1995 through 2020. We find that (i) the turbulence cascade rate derived from a Kolmogorov phenomenology and an IK phenomenology changes with solar cycle, such that the cascade rate is largest during solar maximum and smallest during solar minimum; (ii) the turbulence energy Kolmogorov cascade rate increases fromθUB(angle between mean magnetic field and velocity) = 0° to 90° and peaks nearθUB= 90°, and then decreases asθUBtends to 180°; (iii) the 2D turbulence heating rate is larger than the slab heating rate; (iv) the 2D and slab fluctuating magnetic energy density cascade rates are larger than the corresponding cascade rates of the fluctuating kinetic energy; and (v) the total turbulence energy cascade rate is positively correlated with the solar wind speed and temperature and the normalized cross-helicity cascade rate. Finally, we find that the total turbulent energy Kolmogorov cascade rate is larger than the IK cascade rate.
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Synthesis of Noraugustamine and Development of an Oxidative Heck/Aza-Wacker Cascade Cyclization
ABSTRACT: Radical and transition metal-catalyzed cascade cyclization strategies were investigated toward the syn-thesis of the tetracyclic core of the augustamine-type Amaryllidaceae alkaloids. These studies resulted in the synthesis of noraugustamine and the development of an oxidative Heck/aza-Wacker cascade forming two rings, a C–N bond, and an all-carbon quaternary center in a single step.
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- Award ID(s):
- 1800536
- PAR ID:
- 10326786
- Date Published:
- Journal Name:
- ACS
- ISSN:
- 1165-8223
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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