Planetary nebulae (PNe) exist in a range of different morphologies, from very simple and symmetric round shells, to elliptical, bipolar, and even quadrupolar shapes. They present extremely complex ensembles of filaments, knots, ansae, and shell multiplicity. It is then overwhelmingly complicated to derive reasonable evolutionary paths to justify the observed shapes of PNe. The confrontation bet...

Mach’s principle states that the local inertial properies of matter are determined by the global matter distribution in the universe. In 1958 Cocconi and Salpeter suggested that due to the quadrupolar assymetry of matter in the local galaxy about the earth, inertia on earth would be slightly anisotropic, leading to unequal level splittings of nuclei in a magnetic field [1,2]. Hughes, et al., Dr...

SOEs (sulfite-oxidizing enzymes) are physiologically vital and occur in all forms of life. During the catalytic cycle, the five-co-ordinate square pyramidal oxo-molybdenum active site passes through the Mo(V) state, and intimate details of the structure can be obtained from variable frequency pulsed EPR spectroscopy through the hyperfine and nuclear quadrupole interactions of nearby magnetic nu...

In this work we applied a quantum circuit treatment to describe the nuclear spin relaxation. From the Redfield theory, we were able to describe the quadrupolar relaxation as a computational process in the case of spin 3/2 systems, through a model in which the environment is comprised by five qubits and three different quantum noise channels. The interaction between the environment and the spin ...

Ž . We report the first observation of residual dipolar couplings in magic-angle-spinning MAS and multiple quantum Ž . magic-angle-spinning MQMAS NMR spectra of half-integer quadrupolar nuclei. In particular, the fine spectral splittings observed in the B MAS spectrum of crystalline triethanolamine borate are attributed to the residual B–N dipolar coupling, which is not completely averaged by M...

Heteronuclear multiple-quantum coherence (HMQC) pulse sequences for establishing heteronuclear correlation in solid-state nuclear magnetic resonance (NMR) between 35Cl and 1H nuclei chloride salts under fast (60 kHz) magic-angle spinning (MAS) at high field (a Larmor frequency of 850 MHz) are investigated. Specifically, recoupling the 35Cl–1H dipolar interaction using rotary with phase inversio...

We study the time-fluctuating magnetic gradient noise mechanisms in pairs of Si/SiGe quantum dots using exchange echo spectroscopy. find through a combination spectral inversion and correspondence to theoretical modeling that quadrupolar precession $^{73}$Ge nuclei play key role spin-echo decay time $T_2$, with characteristic dependence on field width Si well. The peaks appear at fundamental fi...

Classical trajectory (Monte Carlo) calculation is used to calculate collision rate constants of ion-quadrupolar molecule interactions for the H¯+C2H2 system. The method presented here takes into account the effect of the induced dipole-induced dipole potential on ion-quadrupolar molecule collision rate constants. It is also assumed that the colliding particles have a d...

We describe the catalytic applications of new solid-state NMR experiments, which provide high-resolution two-dimensional heteronuclear correlation (HETCOR) spectra using through-space and through-bond interactions between nuclear spins. These methods are applied to several microporous framework aluminophosphates and to a new type of ZSM-5-based petrochemical catalysts. Solid-state nuclear magne...