EC08-703 Drinking Water Treatment: An Overview

Consumers concerned about their water quality must sort through an assortment of information to determine what contaminants are present, which contaminants are of real concern and the appropriate response and treatment that will be most effective for their particular situation. This 2008 extension circular provides an overview of household water problems, causes and potential­ health effects. The problem then can be matched to appropriate treatment method(s) for further investigation. The treatment methods listed in this guide are for household water problems requiring prolonged treatment

G08-1489 Drinking Water Treatment: Activated Carbon Filtration

Activated carbon filtration can effectively reduce certain organic compounds and chlorine in drinking water. It can also reduce the quantity of lead, dissolved radon, and harmless taste- and odor-causing compounds. This 2008 NebGuide discusses the principles, processes, and requirements of activated carbon filtration systems for the domestic (household) user

SPH-based simulation of multi-material asteroid collisions

We give a brief introduction to smoothed particle hydrodynamics methods for continuum mechanics. Specifically, we present our 3D SPH code to simulate and analyze collisions of asteroids consisting of two types of material: basaltic rock and ice. We consider effects like brittle failure, fragmentation, and merging in different impact scenarios. After validating our code against previously published results we present first collision results based on measured values for the Weibull flaw distribution parameters of basalt.Comment: Accepted and to be published in Astronomical Note

Asteroid flux towards circumprimary habitable zones in binary star systems: I. Statistical Overview

So far, multiple stellar systems harbor more than 130 extra solar planets. Dynamical simulations show that the outcome of planetary formation process can lead to various planetary architecture (i.e. location, size, mass and water content) when the star system is single or double. In the late phase of planetary formation, when embryo-sized objects dominate the inner region of the system, asteroids are also present and can provide additional material for objects inside the habitable zone (hereafter HZ). In this study, we make a comparison of several binary star systems and their efficiency to move icy asteroids from beyond the snow-line into orbits crossing the HZ. We modeled a belt of 10000 asteroids (remnants from the late phase of planetary formation process) beyond the snow-line. The planetesimals are placed randomly around the primary star and move under the gravitational influence of the two stars and a gas giant. As the planetesimals do not interact with each other, we divided the belt into 100 subrings which were separately integrated. In this statistical study, several double star configurations with a G-type star as primary are investigated. Our results show that small bodies also participate in bearing a non-negligible amount of water to the HZ. The proximity of a companion moving on an eccentric orbit increases the flux of asteroids to the HZ, which could result into a more efficient water transport on a short timescale, causing a heavy bombardment. In contrast to asteroids moving under the gravitational perturbations of one G-type star and a gas giant, we show that the presence of a companion star can not only favor a faster depletion of our disk of planetesimals but can also bring 4 -- 5 times more water into the whole HZ.Comment: Accepted for publication in A&