Particle parameter analyzing system

An X-Y plotter circuit apparatus is described which displays an input pulse representing particle parameter information, that would ordinarily appear on the screen of an oscilloscope as a rectangular pulse, as a single dot positioned on the screen where the upper right hand corner of the input pulse would have appeared. If another event occurs, and it is desired to display this event, the apparatus is provided to replace the dot with a short horizontal line

A solid-state low-noise preamplifier

Solid state low noise preamplifier for particle detector of electrostatic accelerator syste

Oscilloscope used as X-Y plotter or two-dimensional analyzer

Oscilloscope used as an X-Y plotter or two-dimensional analyzer tags each point with a yes or no, depending on a third parameter. The usual square-wave pulse is replaced on the scope by a single information-bearing dot which lengthens to a dash in response to a simultaneous event

Aoyama Gakuin University, Japan

Poster created by students in the 2019 IWU Freeman Asia Internship Program

Immiscible two-phase flow in porous media: Effective rheology in the continuum limit

It is becoming increasingly clear that there is a regime in immiscible two-phase flow in porous media where the flow rate depends of the pressure drop as a power law with exponent different than one. This occurs when the capillary forces and viscous forces both influence the flow. At higher flow rates, where the viscous forces dominate, the flow rate depends linearly on the pressure drop. The question we pose here is what happens to the linear regime when the system size is increased. Based on analytical calculations using the capillary fiber bundle model and on numerical simulations using a dynamical network model, we find that the non-linear regime moves towards smaller and smaller pressure gradients as the system size grows.Comment: 10 pages, 6 figure

Acid-base properties of carbon black surfaces

The surface properties of carbon blacks reflect not only Van der Waals forces due to carbon, but also chemical properties of groups formed on carbon black surfaces by reactions with environmental substances (e.g. water, oxygen, etc.). The present work constitutes a study of such groups

Flow-Area Relations in Immiscible Two-Phase Flow in Porous Media

We present a theoretical framework for immiscible incompressible two-phase flow in homogeneous porous media that connects the distribution of local fluid velocities to the average seepage velocities. By dividing the pore area along a cross-section transversal to the average flow direction up into differential areas associated with the local flow velocities, we construct a distribution function that allows us not only to re-establish existing relationships between the seepage velocities of the immiscible fluids, but also to find new relations between their higher moments. We support and demonstrate the formalism through numerical simulations using a dynamic pore-network model for immiscible two-phase flow with two- and three-dimensional pore networks. Our numerical results are in agreement with the theoretical considerations.Comment: 12 pages, 5 figure