SEARCH · Engineering Papers
Results for “PENETRATION”
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.
Dynamic Covalent Bond Exchange Enhances Penetrant Diffusion in Dense Vitrimers
Not provided.
Interfacial Penetration Drives Anomalous Domain Spacing in Strongly Segregated Linear-Bottlebrush Copolymers
Explore the source record for details and available documents.
Structure-Based Optimization of Selective and Brain Penetrant CK1δ Inhibitors for the Treatment of Circadian Disruptions
Not provided.
Vorasidenib (AG-881): A First-in-Class, Brain-Penetrant Dual Inhibitor of Mutant IDH1 and 2 for Treatment of Glioma
Abstract not provided
Cell-Penetrating Peptide Delivery of Nucleic Acid Cargo to Emiliania huxleyi , a Calcifying Marine Coccolithophore
Not provided.
Penetration and preferential binding of charged nanoparticles to mixed lipid monolayers: interplay o
Explore the source record for details and available documents.
Penetrant-induced plasticization in microporous polymer membranes
This review provides a comprehensive overview on the effects of plasticization on microporous polymer membranes, as well as strategies to mitigate this phenomenon for gas separation applications.
Analysis of thermal grooving effects on vortex penetration in vapor-diffused Nb 3 Sn
While Nb 3 Sn theoretically offers better superconducting radio-frequency (RF) cavity performance (Q 0 and E acc ) to Nb at any given temperature, peak RF magnetic fields consistently fall short of the ~400 mT prediction. The relatively rough topography of vapor-diffused Nb 3 Sn is widely conjectured to be one of the factors that limit the attainable performance of Nb 3 Sn-coated Nb cavities prepared via Sn vapor diffusion. Here we investigate the effect of coating duration on the topography of vapor-diffused Nb 3 Sn on Nb and calculate the associated magnetic field enhancement and superheating field suppression factors using atomic force microscopy topographies. It is shown that the thermally grooved grain boundaries are major defects which may contribute to a substantial decrease in the achievable accelerating field. Further, the severity of these grooves increases with total coating duration due to the deepening of thermal grooves during the coating process.
Empirical scaling of the n = 2 error field penetration threshold in tokamaks
Abstract not provided.
Solving the one-dimensional penetration problem for the fission channel in the statistical Hauser-Feshbach theory
Here we solve the Schrödinger equation for an arbitrary one-dimensional potential energy to calculate the transmission coefficient in the fission channel of compound nucleus reactions. We incorporate the calculated transmission coefficients into the statistical Hauser-Feshbach model calculation for neutron-induced reactions on 235,238 U and 239 Pu. The one-dimensional model reproduces the evaluated fission cross section data reasonably well considering the limited number of model parameters involved. A resonance-like structure appears in the transmission coefficient for a double-humped fission barrier shape that includes an intermediate well, which is understood to be a quantum mechanical effect in the fission channel. The calculated fission cross sections for the neutron-induced reactions on 235,238 U and 239 Pu all exhibit a similar structure.
Barrier penetration in a discrete-basis formalism
The dynamics of a many-particle system are often modeled by mapping the Hamiltonian into a Schrödinger equation. An alternative approach is to solve the Hamiltonian equations directly in a model space of many-body configurations. In a previous paper the numerical convergence of the two approaches was compared with a simplified treatment of the Hamiltonian representation. Here, we extend the comparison to the nonorthogonal model spaces that would be obtained by the generator-coordinate method. With a suitable choice of the collective-variable grid, a configuration-interaction Hamiltonian can reproduce the Schrödinger dynamics very well. Furthermore, the method as implemented here requires that the barrier height is not much larger than the zero-point energy in the collective coordinates of the configurations.
Role of momentum in the generator-coordinate method applied to barrier penetration
Nuclear fission at barrier-top energies is conventionally modeled by a one-dimensional Schrödinger equation applied to internal fission channels, but that treatment is hard to justify in the configuration-interaction approach to nuclear Hamiltonians. Here we show that inclusion of states of finite momentum by the generator coordinate method (GCM) considerably extends the range of energies at which GCM-based Hamiltonians could reproduce the Schrödinger treatment. Furthermore, the transmission probabilities for crossing the barrier are calculated by a discrete version of Kohn's variational method, which may also be useful for other systems of interacting fermions.
Evaluation of Data-Enhanced Hierarchical Control for Distribution Feeders With High PV Penetration
Not Available