Results 31 to 40 of about 724,876 (319)

Extension of the QuickFF force field protocol for an improved accuracy of structural, vibrational, mechanical and thermal properties of metal-organic frameworks [PDF]

, 2018
QuickFF was originally launched in 2015 to derive accurate force fields for isolated and complex molecular systems in a quick and easy way. Apart from the general applicability, the functionality was especially tested for metal-organic frameworks (MOFs),
Van Speybroeck, Veronique, Vandenbrande, Steven, Vanduyfhuys, Louis, Verstraelen, Toon, Waroquier, Michel, Wieme, Jelle   +5 more
core   +2 more sources

Analyzing false positives of four questions in the Force Concept Inventory

Physical Review Physics Education Research, 2018
In this study, we analyze the systematic error from false positives of the Force Concept Inventory (FCI). We compare the systematic errors of question 6 (Q.6), Q.7, and Q.16, for which clearly erroneous reasoning has been found, with Q.5, for which ...
Jun-ichiro Yasuda, Naohiro Mae, Michael M. Hull, Masa-aki Taniguchi   +3 more
doaj   +1 more source

Expanding Space: the Root of all Evil? [PDF]

, 2007
While it remains the staple of virtually all cosmological teaching, the concept of expanding space in explaining the increasing separation of galaxies has recently come under fire as a dangerous idea whose application leads to the development of ...
Chodorowski, Dicke, Geraint F. Lewis, Grøn, Hobson, J. Berian James, Luke A. Barnes, Matthew J. Francis, Rees, Weinberg, Whiting   +10 more
core   +1 more source

Probing Pulsar Winds Using Inverse Compton Scattering [PDF]

, 1999
We investigate the effects of inverse Compton scattering by electrons and positrons in the unshocked winds of rotationally-powered binary pulsars. This process can scatter low energy target photons to produce gamma rays with energies from MeV to TeV. The
Aschenbach, Ball, Bell, Chernyakova, de Jager, Emmering, Harding, Hester, Hirayama, Ho, J.G. Kirk, Johnston, Johnston, Johnston, Johnston, Jones, Kaspi, Kaspi, Kennel, Kirk, Lewis Ball, Luo, Mastichiadis, Melatos, Qiao, Rees, Tavani, Tavani, Yoshikoshi, Zhang   +29 more
core   +3 more sources

Experimental assessment for non-monolithic slab-column connections

Ain Shams Engineering Journal, 2021
It is common practice to use non-monolithic connections to connect the new flat slabs to the existing columns for upgrading the stories number of the existing buildings, despite the lack of design guidelines for the non-monolithic connection.
Ahmed Abdel-hady, Shady Salem, Ayman Khalil, Hazam Abdel-Latif   +3 more
doaj   +1 more source

Full and half-wavelength ultrasonic percussive drills [PDF]

, 2018
Ultrasonic-percussive drills are a leading technology for small rock drilling applications where power and weight-on-bit are at a premium. The concept uses ultrasonic vibrations to excite an oscillatory motion in a free-mass, which then delivers ...
Harkness, Patrick, Li, Xuan, Lucas, Margaret   +2 more
core   +1 more source

Mass loss by a scalar charge in an expanding universe [PDF]

, 2002
We study the phenomenon of mass loss by a scalar charge -- a point particle that acts a source for a noninteracting scalar field -- in an expanding universe.
A.S. Eddington, Abraham I. Harte, B.S. DeWitt, E. Seidel, Eric Poisson, I.H. Redmount, L.M. Burko, Lior M. Burko, M.W. Choptuik, P.A.M. Dirac, P.A.M. Dirac, R.H. Dicke, T.C. Quinn, W.E. Thirring   +13 more
core   +2 more sources

Effects of Four Types of Pre-swirls on the Leakage, Flow Field, and Fluid-Induced Force of the Rotary Straight-through Labyrinth Gas Seal

Chinese Journal of Mechanical Engineering, 2019
The labyrinth seal in turbomachinery is a key element that restricts leakage flow among rotor-stator clearances from high-pressure regions to low-pressure regions.
Qingfeng Wang, Lidong He
doaj   +1 more source

Unification of the four forces in the Spin(11,1) geometric algebra

Physica Scripta, 2023
Abstract SO(10), or equivalently its covering group Spin(10), is a well-known promising grand unified group that contains the standard-model group. The spinors of the group Spin(N) of rotations in N spacetime dimensions are indexed by a bitcode with [N/2] bits. Fermions in Spin(10) are described by five bits yzrgb, consisting of two weak
Andrew J S Hamilton, Tyler McMaken
openaire   +2 more sources

Structural and functional asymmetry of the lower limb related to gravitational acceleration tolerance

iScience
Summary: This study investigates the physiological effects of intensive physical training on femoral cartilage morphology and limb asymmetry in strength in air force cadets.
Jun-Young Sung, In-Ki Kim, Kyu-Lim Lee
doaj   +1 more source