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This public dataset contains openly-documented, machine readable digital research data corresponding to figures published in J.D. Weberski et al., “Taylor Limit Studies for Local Helicity Injection Plasma Startup,” Physics of Plasmas 32 , 062510 (2025).
This public dataset contains openly-documented, machine readable digital research data corresponding to figures published in C.E. Schaefer et al., “Modeling of Injected Current Stream-Induced 3D Perturbations in Local Helicity Injection Plasmas,” accepted for publication in Physics of Plasmas.
This public dataset contains openly-documented, machine readable digital research data corresponding to figures published in A.S. Rajendra et al. , “Damage to Injector Component Surfaces During Local Helicity Injection in Pegasus-III,” accepted for publication in Journal of Fusion Energy .
This public dataset contains openly-documented, machine readable digital research data corresponding to figures published in C. Rodriguez Sanchez et al., “ Impurity Dynamics and Radiative Losses During Local Helicity Injection Startup in the Pegasus-III Spherical Tokamak,” accepted for publication in Physics of Plasmas .
The twist-bend nematic liquid crystal phase is a three-dimensional fluid in which achiral bent molecules spontaneously form an orientationally ordered, macroscopically chiral, heliconical winding of a ten nanometer-scale pitch in the absence of positional ordering. Here, the structure of the twist-bend phase of the bent dimer CB7CB and its mixtures with 5CB is characterized, revealing a hidden invariance of the self-assembly of the twist-bend structure of CB7CB, such that over a wide range of concentrations and temperatures, the helix pitch and cone angle change as if the ground state for a pitch of the TB helix is an inextensible heliconical ribbon along the contour formed by following the local molecular long axis (the director). Remarkably, the distance along the length for a single turn of this helix is given by 2πR mol , where R mol is the radius of bend curvature of a single all-trans CB7CB molecule. This relationship emerges from frustrated steric packing due to the bent molecular shape: space in the fluid that is hard to fill attracts the most flexible molecular subcomponents, a theme of nanosegregation that generates self-assembled, oligomer-like correlations of interlocking bent molecules in the form of a brickwork-like tiling of pairs of molecular strands into duplex double-helical chains. At higher temperatures in the twist-bend phase, the cone angle is small, the director contour is nearly along the helix axis z, and the duplex chains are sequences of biaxial elements formed by overlapping half-molecule pairs, with an approximately 45° rotation of the biaxis between each such element along the chain.
By extending our analysis and simulations of our K -decay data set to allow the asymmetry with respect to nuclear spin to vary with energy , we have gained sensitivity to new physics that depends on a helicity factor for the , . In particular, we constrain Lorentz scalar and tensor quark-lepton interaction strengths at a sensitivity complementary to the similar Fierz interference term in neutron decay. Our result for that new physics is = 0.033 0.084 (stat) 0.039 (syst), consistent with the standard model electroweak interaction value . We consider presently achieved complementarity to -decay and particle physics experiments, along with projectable technical improvements to our method.
Isolation of closely spaced transmitting and receiving frequencies of an antenna without insertion loss by filtering the receiver input is accomplished by an inner conductor with two winding helices and an outer conductor of aluminum. A tuning slug is at either end of the inner conductor form.
End effect and pressure patterns in viscoseal with smooth rotor and stationary helically grooved housing
Helical groove viscosity seal using sodium and water as sealed fluids
Helical seal is used to seal bolted flange joints in a high temperature environment. The seal design incorporates a new cross-sectional shape, a metal strip with a slight radius, and the use of premolded asbestos. It provides equal load distribution under compression loads, allows for minimum loss and recovery values, and increases the temperature range.
Dielectric constant of plasma in direct pinch magnetic field and in direct helical magnetic field
Helical instability of positive column in crossed fields and in annular plasma configurations
Calculation of electron gun for producing helical electron beams with prescribed high transverse over longitudinal electron energy ratio
Systems design analysis of helically-wound magnetic tape and mechanical tape transport
FORTRAN subroutines for determining intersections of nuclear particle flight path and wall of helical tubular duct
Single tube-in-shell water-boiling heat exchanger performance with helical wire insert and flow stabilizing devices
Helical instability theory for positive hollow plasma column in magnetic field with shear
Radial profile of perturbation density at onset of helical instability in positive plasma column