Results 121 to 130 of about 44,482 (164)

Counter-Rotating Ring Currents in Coronene and Corannulene

Angewandte Chemie International Edition, 2001
Explicit ab initio current-density maps contradict the annulene-within-an-annulene model of [n]circulenes: in both coronene and corannulene the expected diamagnetic current on the perimeter is opposed by the central, paramagnetic ring current.
Steiner, E., Fowler, P.W., Jenneskens, L.W.   +2 more
openaire   +3 more sources

A Counter Rotating Power Drill for Needle Biopsy

Clinical Orthopaedics and Related Research, 1984
A new needle biopsy instrument and technique are described. The needle is powered and due to its scissor-like arrangement can provide a core of both soft and hard tissue, preserving histologic detail. The needle has been used in 25 patients, in all of whom an appropriate specimen was obtained.
L S, Matthews, E M, Braunstein
openaire   +2 more sources

Diffractively corrected counter-rotating Risley prisms

Applied Optics, 2015
Using the vector refraction equation and the vector diffraction equation, we obtain the expressions of the direction cosines of the refractive rays for the two wedge prisms, and the direction cosines of the diffractive rays for two wedge grisms, in which diffractive gratings were etched into the prism faces to correct the chromatic aberrations.
Xin, Nie, Hongfang, Yang, Changxi, Xue
openaire   +2 more sources

Counter rotating STOL discs

Aircraft Engineering and Aerospace Technology, 1972
A ROTATING PLASTIC DISC, such as a Frisbee, indicates high lift coefficients. To examine this phenomenon, experimental research was conducted, using a specially‐constructed rotating water tank. Test results demonstrated both lift increase and drag decrease for rotating discs compared to values for nonrotating discs.
openaire   +1 more source

The counter-rotating terms in the superradiance

Il Nuovo Cimento D, 1986
It is pointed out that the counter-rotating terms play an important role in the superradiance of the first kind, in which the atomic system is initially in an uncorrelated state with maximal dipole moment. If the counter-rotating terms are added to the master equation for the Dicke model derived by Agarwal and Bonifacioet al., the numerical solutions ...
openaire   +1 more source

Visualisation of counter-rotating ring currents in kekulene

Chemical Communications, 2001
Current-density maps for kekulene 1 computed using an ab initio all-electron distributed-origin method show global diamagnetic and paramagnetic circulations around outer and inner perimeters (‘rim’ and ‘hub’), subsuming six local benzenoid diamagnetic π circulations, in qualitative agreement with the Huckel–London π model, but in ...
Steiner E., Fowler P. W., Jenneskens L. W., Acocella A.   +3 more
openaire   +3 more sources

A Study on Counter Rotating Turbine/Counter Rotating Propfan Integrated Performance Simulation Methodology

2023 7th International Conference on Electrical, Mechanical and Computer Engineering (ICEMCE), 2023
Dalu Cao, Xiyun Wu, Xuerui Zeng, Huairong Chen   +3 more
openaire   +1 more source

Kantowski Sachs universes with counter-rotating dust

Classical and Quantum Gravity, 2002
In 1939, Einstein solved the field equations of general relativity to describe a cluster of particles moving in circular orbits about the center of the system. These Einstein clusters have been studied extensively. In a series of recent papers (see Zbl 0999.83072, Zbl 1001.83032, and Zbl 1005.83043), the author presented a solution of Einstein's ...
openaire   +2 more sources

The effect of constraining mediolateral ankle moments and foot placement on the use of the counter-rotation mechanism during walking

Journal of Biomechanics, 2022
Joke Spildooren, J H Van Dieën, S M Bruijn   +2 more
exaly  

Insights into the nonlinear behaviors of dual-rotor systems with inter-shaft rub-impact under co-rotation and counter-rotation conditions

International Journal of Non-Linear Mechanics, 2022
Yu Pingchao
exaly