533 research outputs found
A numerical method for analyzing a passive fault current limiter considering hysteresis
Structural Basis of the Association of HIV-1 Matrix Protein with DNA
HIV-1 matrix (MA) is a multifunctional protein that is synthesized as a polyprotein that is cleaved by protease during viral maturation. MA contains a cluster of basic residues whose role is controversial. Proposed functions include membrane anchoring, facilitating viral assembly, and directing nuclear import of the viral DNA. Since MA has been reported to be a component of the preintegration complex (PIC), we have used NMR to probe its interaction with other PIC components. We show that MA interacts with DNA and this is likely sufficient to account for its association with the PIC
Effect of lattice volume and strain on the conductivity of BaCeY-oxide ceramic proton conductors
In-situ electrochemical impedance spectroscopy was used to study the effect
of lattice volume and strain on the proton conductivity of the yttrium-doped
barium cerate proton conductor by applying the hydrostatic pressure up to 1.25
GPa. An increase from 0.62 eV to 0.73 eV in the activation energy of the bulk
conductivity was found with increasing pressure during a unit cell volume
change of 0.7%, confirming a previously suggested correlation between lattice
volume and proton diffusivity in the crystal lattice. One strategy worth trying
in the future development of the ceramic proton conductors could be to expand
the lattice and potentially lower the activation energy under tensile strain
Field Distribution of a Flux-Concentration Type Linear Induction Motor
This paper has reported the eddy current and secondary-core flux density distributions of a flux-concentration type linear induction motor (FCLIM) based on the effect of flux-concentration by eddy currents. In the developed FCLIM, the slot leakage flux is reduced and as a result more flux is concentrated into the air gap. Thrust characteristics are also determined using the parameters of the equivalent circuit. It is observed from the calculated and experimental results that the developed FCLIM has better performance than that of the normal type tubular LIM
A Numerical Method for Analyzing a Passive Fault Current Limiter Considering Hysteresis
Fast transient analysis of a passive fault current limiter (FCL) using permanent magnets can be done by direct numerical solution of a single non-linear differential equation. The non-linear B-H excursion that is caused by hysteresis is incorporated in the computation using a transient hysteresis model. Rational fractions are used to represent the parent hysteresis loop curves. Since the method uses preconstructed expressions as applicable to FCL schemes only, computation time required is less
Application of the Repulsive-Type Magnetic Bearing for Manufacturing Micromass Measurement Balance Equipment
金沢大学環日本海域環境研究センター生体機能計測研究部
Dopant site selectivity in BaCe0.85M0.15O3-δ by extended x-ray absorption fine structure
Mapping the encounter state of a transient protein complex by PRE NMR spectroscopy
Many biomolecular interactions proceed via a short-lived encounter state, consisting of multiple, lowly-populated species invisible to most experimental techniques. Recent development of paramagnetic relaxation enhancement (PRE) nuclear magnetic resonance (NMR) spectroscopy has allowed to directly visualize such transient intermediates in a number of protein-protein and protein-DNA complexes. Here we present an analysis of the recently published PRE NMR data for a protein complex of yeast cytochrome c (Cc) and cytochrome c peroxidase (CcP). First, we describe a simple, general method to map out the spatial and temporal distributions of binding geometries constituting the Cc-CcP encounter state. We show that the spatiotemporal mapping provides a reliable estimate of the experimental coverage and, at higher coverage levels, allows to delineate the conformational space sampled by the minor species. To further refine the encounter state, we performed PRE-based ensemble simulations. The generated solutions reproduce well the experimental data and lie within the allowed regions of the encounter maps, confirming the validity of the mapping approach. The refined encounter ensembles are distributed predominantly in a region encompassing the dominant form of the complex, providing experimental proof for the results of classical theoretical simulations
The effect of compressive strain on the Raman modes of the dry and hydrated BaCe0.8Y0.2O3 proton conductor
The BaCe0.8Y0.2O3-{\delta} proton conductor under hydration and under
compressive strain has been analyzed with high pressure Raman spectroscopy and
high pressure x-ray diffraction. The pressure dependent variation of the Ag and
B2g bending modes from the O-Ce-O unit is suppressed when the proton conductor
is hydrated, affecting directly the proton transfer by locally changing the
electron density of the oxygen ions. Compressive strain causes a hardening of
the Ce-O stretching bond. The activation barrier for proton conductivity is
raised, in line with recent findings using high pressure and high temperature
impedance spectroscopy. The increasing Raman frequency of the B1g and B3g modes
thus implies that the phonons become hardened and increase the vibration energy
in the a-c crystal plane upon compressive strain, whereas phonons are relaxed
in the b-axis, and thus reveal softening of the Ag and B2g modes. Lattice
toughening in the a-c crystal plane raises therefore a higher activation
barrier for proton transfer and thus anisotropic conductivity. The experimental
findings of the interaction of protons with the ceramic host lattice under
external strain may provide a general guideline for yet to develop epitaxial
strained proton conducting thin film systems with high proton mobility and low
activation energy
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