Modeling of Desalination Concentrate Storage Options for Future Recovery and Use

Ciudad Juárez, Chihuahua, a rapidly growing city across the Rio Grande from El Paso, Texas with a 2005 population in excess of 1.2 million, relies exclusively on ground water from an aquifer known as the Hueco Bolson. The aquifer’s fresh water is being depleted and it is degrading in quality due to the lateral inflow of brackish water. Although the Hueco Bolson’s fresh water is diminishing, it still contains a considerable quantity of brackish water. This paper defines the feasibility of using desalination technology in conjunction with concentrate storage to extend the ‘life’ of the Juárez portion of the Hueco Bolson. Well injection of the concentrate was analyzed based on the premise that the cones of depression created by well pumping could provide a storage area for the concentrate. So doing would enable the brackish concentrate to be ‘stored’ for future use when advances in desalination technology will render the stored concentrate into an economically recoverable resource , unlike evaporation ponds that result in the permanent loss of water due to vaporization. The research team used a combination of three software systems for this portion of the analysis: a ground water modeling software, a mass transport extension to the ground water modeling software, and GIS software to facilitate the visualization of model outputs. The technical report on which this paper is based was authored by Turner and Hamlyn (2004)

Picoradian deflection measurement with an interferometric quasi-autocollimator using weak value amplification

We present an "interferometric quasi-autocollimator" that employs weak value amplification to measure angular deflections of a target mirror. The device has been designed to be insensitive to all translations of the target. We present a conceptual explanation of the amplification effect used by the device. An implementation of the device demonstrates sensitivities better than 10 picoradians per root hertz between 10 and 200 hertz.Comment: To be published in Optics Letter

Interferometric Quasi-Autocollimator

Systems and method are disclosed for measuring small angular deflections of a target using weak value amplification. A system includes a beam source, a beam splitter, a target reflecting surface, a photodetector, and a processor. The beam source generates an input beam that is split into first and second beams by the beam splitter. The first and second beams are propagated to the target reflecting surface, at least partially superimposed at the target reflecting surface, and incident to the target reflecting surface normal to the target reflecting surface. The first beam is reflected an additional even number of times during propagation to the photodetector. The second beam is reflected an additional odd number of times during propagation to the photodetector. The first and second beams interfere at the photodetector so as to produce interference patterns. The interference patterns are interpreted to measure angular deflections of the target reflecting surface

Climate change in the subtropics: The impacts of projected averages and variability on banana productivity

The potential for bananas to produce year round is best expressed when water is abundant and daily temperatures are in the range of 20-30°C. Zones with these conditions produce fruit for the global market. However, banana production, mainly for national markets, has developed in many subtropical areas under less than optimum conditions. Bananas are an important cash crop in southern Brazil, Paraguay and Argentina, in countries of North Africa, the Middle East and southern Africa, and in China and northern India. In these regions, bananas are subject to sub-optimum temperatures and short days. Highly favorable temperatures and long days in the summer may also include short periods of extreme temperatures above 35°C, while rainfall is also highly variable. The effects of climate change on selected subtropical production areas were modeled in a two-step procedure using the EcoCrop model, under current growing conditions and for 2020 and 2050 using a set of 19 IPCC (Intergovernmental Panel on Climate Change) Global Climate Models (GCMs) under the SRES-A2 (business as usual) emission scenario. The modeling showed that current suitability for banana production in the subtropics is much lower than in the tropics with great variation in suitability within the subtropics. Of nine subtropical regions considered, two have improved conditions by 2020s, four are largely unaffected and three have a lower suitability. Our analysis also showed that, in terms of environmental conditions, certain sites are widely represented globally, offering options for technology transfer between sites. Other sites have few similar sites, which means that sites need to be carefully selected for approaches to technology development and transfer. The study leveraged site-specific information with widely available tools to understand potential effects of climate change in the subtropics. However, in order to fully understand the impacts of climate change on banana, the modeling tools used here need to be fully suited for semi-perennial crops to capture the effects of seasonal temperature and rainfall variability on crop cycle length and potential yields

A Bulloch Tapestry

The title for this collection was inspired by a poem by Rita Turner Wall. The poem is included in this book, along with articles by C.D. Sheley, Daniel Good, James D. Morgan, Gregory Alan Baker, Paul T. Marlott, and Charles Bonds, David R. Williams. Topics covered by these articles are the history of the Bill Olliff House; the historical geography of Arcola, New Hope, and Denmark, Georgia; the lives of Luetta Leverette Moore and Amanda Love Smith; and the letters of Confederate soldier Asbury Wesley Hodges. Also included are letters to Union soldier Perry Lovejoy, submitted by Bill Lovejoy and transcribed by Evelyn Mabry. The index to this collection was compiled by Julius Ariail.https://digitalcommons.georgiasouthern.edu/bchs-pubs/1001/thumbnail.jp