Results 31 to 40 of about 441,091 (198)

Morphological characteristics and permeability evolution of deep mine gas drainage boreholes

Frontiers in Earth Science, 2022
Structural coal has low permeability and high gas content. The increase of mining depth seriously restricts the safe mining of deep mines. Hydraulic flushing is the main means of gas extraction.
Xiao Liu, Tianxiang Jing, Haixiao Lin, Dequan Xuan, Yong Li, Sen Xu   +5 more
doaj   +1 more source

Quantum Schwarzschild geometry in effective field theory models of gravity [PDF]

Physical Review D, 2023
The Schwarzschild geometry is investigated within the context of effective-field-theory models of gravity. Starting from its harmonic-coordinate expression, we derive the metric in standard coordinates by keeping the leading one-loop quantum ...
Emmanuele Battista
semanticscholar   +1 more source

Flavor Twisted Boundary Conditions, Pion Momentum, and the Pion Electromagnetic Form Factor [PDF]

, 2006
We investigate the utility of partially twisted boundary conditions in lattice calculations of meson observables. For dynamical simulations, we show that the pion dispersion relation is modified by volume effects.
Aarts, Arndt, B.C. Tiburzi, Bedaque, Bedaque, Bernard, Bernard, Bonnet, Brommel, Bucarelli, Bunton, de Divitiis, Detmold, Donoghue, Draper, F.-J. Jiang, Flynn, Gasser, Gasser, Gasser, Golterman, Gross, Guadagnoli, Guagnelli, Hashimoto, Kim, Kim, Kiskis, Kiskis, Luscher, Martinelli, Roberge, Sachrajda, Sharpe, Sharpe, Sharpe, Tiburzi, Tiburzi, Wiese, Zinn-Justin   +39 more
core   +2 more sources

Research on determination method of effective drainage radius of gas drainage borehole

Gong-kuang zidonghua, 2020
In order to solve the problems of complex process and lower accuracy in current determination method of effective drainage radius of gas drainage borehole, a determination method of effective drainage radius was put forward, which is based on the law of ...
LIU Dianping, MA Wenwei
doaj   +1 more source

Simulation and analysis of solenoidal ion sources [PDF]

, 2008
We present a detailed analysis and simulation of solenoidal, magnetically confined electron bombardment ion sources, aimed at molecular beam detection. The aim is to achieve high efficiency for singly ionized species while minimizing multiple ionization.
A. P. Jardine, A. R. Alderwick, Bassi D., Boyd T. J. M., Brown I. G., D. A. MacLaren, H. Hedgeland, J. Ellis, MacLaren D. A., W. Allison   +9 more
core   +1 more source

From representative volume element of interacting particles to the extraction of their effective properties.

Optics Express, 2021
The main concern of this investigation was the relation between the representative volume element of the scattered flux from 2D random agglomerates, composed of sub-wavelength interacting particles, and the extraction of their effective electromagnetic ...
Timothée Guerra, D. D. S. Meneses, O. Rozenbaum, C. Blanchard   +3 more
semanticscholar   +1 more source

Study and application on influence mechanism of instability and collapse of drainage borehole on gas drainage

Meitan xuebao, 2023
The instability and collapse of drainage boreholes is one of the key problems that hinder the efficient extraction of coal-bed methane (CBM). In order to solve the problem of instability and collapse of extraction boreholes in soft coal seams, based on ...
Xuebo ZHANG, Hao WANG, Ming YANG, Pan WANG, Linxiu HAN   +4 more
doaj   +1 more source

Characteristic extraction tool for gravitational waveforms [PDF]

, 2011
We develop and calibrate a characteristic waveform extraction tool whose major improvements and corrections of prior versions allow satisfaction of the accuracy standards required for advanced LIGO data analysis. The extraction tool uses a characteristic
Babiuc, M. C., Szilágyi, B., Winicour, J., Zlochower, Y.   +3 more
core   +3 more sources

Morphological characteristics of hydraulic punching holes and optimization of gas extraction parameters

Meikuang Anquan, 2023
At present, in drilling design and evaluation, the shape of hydraulic flushing hole is usually equivalent to cylinder, which is one of the important bases to determine the effective extraction radius.
LIU Xiao, JING Tianxiang, XUAN Dequan, HU Shixiong, LI Yong1, XU Sen
doaj   +1 more source

Extraction of nucleon axial charge and radius from lattice QCD results using baryon chiral perturbation theory [PDF]

, 2017
We calculate the nucleon axial form factor up to the leading one-loop order in a covariant chiral effective field theory with the $\Delta(1232)$ resonance as an explicit degree of freedom.
D. Yao, L. Alvarez-Ruso, M. Vicente-Vacas   +2 more
semanticscholar   +1 more source