Evaluation of a New Disinfection Approach: Efficacy of Chlorine and Bromine Halogenated Contact Disinfection for Reduction of Viruses and Microcystin Toxin

Contaminated drinking water is responsible for causing diarrheal diseases that kill millions of people a year. Additionally, toxin-producing blue-green algae associated with diarrhea and neurologic effects continues to be an issue for many drinking water supplies. Disinfection has been used to reduce these risks. A novel gravity-fed household drinking water system with canisters containing N-halamine bromine or chlorine media was challenged with MS2 bacteriophage and microcystin. Chlorine and bromine systems were effective against this virus, with an mean ± SE reduction of 2.98 ± 0.26 log10 and 5.02 ± 0.19 log10, respectively. Microcystin toxin was reduced by 27.5% and 88.5% to overall mean ± SE concentrations of 1,600 ± 98 ng/L and 259 ± 50 ng/L for the chlorine and bromine canisters, respectively. Only the bromine units consistently produced microcystin effluent < 1,000 ng/L (the World Health Organization recommended level) when challenged with 2,500 ng/L and consistently surpassed the U.S. Environmental Protection Agency virus reduction goal of 99.99%

Pollution release tied to invariant manifolds: A case study for the coast of Florida

High-resolution ocean velocity data has become readily available since the introduction of very high frequency (VHF) radar technology. The vast amount of data generated so far, however, remains largely unused in environmental prediction. In this paper, we use VHF data of the Florida coastline to locate Lagrangian coherent structures (LCS) hidden in ocean surface currents. Such structures govern the spread of organic contaminants and passive drifters that stay confined to the ocean surface. We use the Lagrangian structures in a real-time pollution release scheme that reduces the effect of industrial contamination on the coastal environment

Preliminary design of an amphibious aircraft by the multidisciplinary design optimization approach

In the past few decades, besides the important progress that the aeronautical and aerospace engineering have achieved, the requirement of improving aircrafts performances and features, and the need of devising crafts performing special missions were growing meanwhile. Nevertheless, developing unconventional or innovative configurations the reference data extrapolated by known standard configurations are useless. Thus, the concept of Multidisciplinary Design Optimization, MDO, for the preliminary design of aeronautical and aerospace structures is the natural answer to the challenge that aeronautical and aerospace structures represent especially if new configurations of crafts are requested. Hence, the aim of this paper is to present an MDO procedure and an associated overview of the work code called MAGIC, (Multidisciplinary Aircraft desiGn of Innovative Configurations), for conceptual design of non-conventional aircraft configurations in civil aviation. Accordingly, the relevance of an adequate modeling is an essential issue in order to obtain meaningful designing results. Thus, the intimate link between MDO, modeling, and simulations fields is evident. The algorithms used in MAGIC for modeling structures, aerodynamics, and aeroelasticity are first-principles based, since for innovative configurations the designer cannot rely upon past experience. In addition, we emphasize the conceptual design: thus, the algorithms used must be accurate and efficient, so as to produce accurate predictions with a relatively small computational effort. In the paper presented the structural analysis (statics -including the buckling analysis- and dynamics) has been performed using an external commercial FEM code. Furthermore, since the special condition of ground effect flight is considered, we have adopted the specific methodology introduced by Keldysh-Lavrentiev (KL) and available in the steady aerodynamic case for airfoils in bounded domain in order to evaluate the aerodynamic loads. The efficiency of the proposed methodology is illustrated by applications to specific configurations