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Field application of the Numobag as a portable disposable isolation unit and for treating chemical, radiological or biologically induced wounds

Miller, A.K.; Vaughn, Mark R.

Numotech Inc. has developed the Numobag{trademark}, a disposable, lightweight, wound healing device which produces Topical Hyperbaric Oxygen Therapy (THOT). The Numobag{trademark} is cost effective and has been clinically validated to heal large skin lesions rapidly and has proven to arrest wound advancement from several insidious forms of biological attack including dermal anthrax, small pox, necrotizing fasciitis etc. The Numobag{trademark} can treat mass casualties wounded by chemical/radiological burns or damaging biological exposures. The Numobag{trademark} can be a frontline tool as an isolation unit, reducing cross-contamination and infection of medical personnel. The heightened oxygen content kills organisms on the skin and in the wound, avoids expensive hospital trash disposal procedures, and helps the flesh heal. The Numobag{trademark} requires high purity oxygen. Numotech Inc. is teaming with Sandia National Laboratories and Spektr Conversion in Russia to develop a cost effective, portable, low power oxygen generator.

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Diversionary device history and revolutionary advancements

Grubelich, Mark C.

Diversionary devices also known as flash bangs or stun grenades were first employed about three decades ago. These devices produce a loud bang accompanied by a brilliant flash of light and are employed to temporarily distract or disorient an adversary by overwhelming their visual and auditory senses in order to gain a tactical advantage. Early devices that where employed had numerous shortcomings. Over time, many of these deficiencies were identified and corrected. This evolutionary process led to today's modern diversionary devices. These present-day conventional diversionary devices have undergone evolutionary changes but operate in the same manner as their predecessors. In order to produce the loud bang and brilliant flash of light, a flash powder mixture, usually a combination of potassium perchlorate and aluminum powder is ignited to produce an explosion. In essence these diversionary devices are small pyrotechnic bombs that produce a high point-source pressure in order to achieve the desired far-field effect. This high point-source pressure can make these devices a hazard to the operator, adversaries and hostages even though they are intended for 'less than lethal' roles. A revolutionary diversionary device has been developed that eliminates this high point-source pressure problem and eliminates the need for the hazardous pyrotechnic flash powder composition. This new diversionary device employs a fuel charge that is expelled and ignited in the atmosphere. This process is similar to a fuel air or thermobaric explosion, except that it is a deflagration, not a detonation, thereby reducing the overpressure hazard. This technology reduces the hazard associated with diversionary devices to all involved with their manufacture, transport and use. An overview of the history of diversionary device development and developments at Sandia National Laboratories will be presented.

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Central-station solar hydrogen power plant

Kolb, Gregory J.; Diver, Richard B.; Siegel, Nathan P.

Solar power towers can be used to make hydrogen on a large scale. Electrolyzers could be used to convert solar electricity produced by the power tower to hydrogen, but this process is relatively inefficient. Rather, efficiency can be much improved if solar heat is directly converted to hydrogen via a thermochemical process. In the research summarized here, the marriage of a high-temperature ({approx}1000 C) power tower with a sulfuric acid/hybrid thermochemical cycle was studied. The concept combines a solar power tower, a solid-particle receiver, a particle thermal energy storage system, and a hybrid-sulfuric-acid cycle. The cycle is 'hybrid' because it produces hydrogen with a combination of thermal input and an electrolyzer. This solar thermochemical plant is predicted to produce hydrogen at a much lower cost than a solar-electrolyzer plant of similar size. To date, only small lab-scale tests have been conducted to demonstrate the feasibility of a few of the subsystems and a key immediate issue is demonstration of flow stability within the solid-particle receiver. The paper describes the systems analysis that led to the favorable economic conclusions and discusses the future development path.

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Sequestration of radionuclides and heavy metals by hydroxyapatite doped with Fe, Cu and Sn

Helean, Katheryn B.; Walton, Fotini W.; Neidel, Linnah L.; Larese, Kathleen C.; Salas, Fred S.

Apatite, Ca{sub 5}(PO{sub 4}){sub 3}(F,OH,Cl)(P6{sub 3}/m, Z=2), is the most abundant phosphate mineral on Earth. The end-member hydroxyapatite, Ca{sub 5}(PO{sub 4}){sub 3}OH(P2{sub 1}/b), is the primary mineral component in bones and teeth and tends to scavenge and sequester heavy metals in the human body. Hydroxyapatite has also been shown to be effective at sequestering radionuclides and heavy metals in certain natural systems (Dybowska et al., 2004). Hydroxyapatite has been the focus of many laboratory studies and is utilized for environmental remediation of contaminated sites (Moore et al., 2002). The crystal structure of apatite tolerates a great deal of distortion caused by extensive chemical substitutions. Metal cations (e.g. REE, actinides, K, Na, Mn, Ni, Cu, Co, Zn, Sr, Ba, Pb, Cd, Fe) substitute for Ca, and oxyanions (e.g. AsO{sub 4}{sup 3-}, SO{sub 4}{sup 2-}, CO{sub 3}{sup 2-}, SiO{sub 4}{sup 4-}, CrO{sub 4}{sup 2-}) replace PO{sub 4}{sup 3-} through a series of coupled substitutions that preserve electroneutrality. Owing to the ability of apatite to incorporate 'impurities'(including actinides) gives rise to its proposed use as a waste form for radionuclides. Recent work at Sandia National Laboratory demonstrated that hydroxyapatite has a strong affinity for U, Pu, Np, Sr and Tc reduced from pertechnetate (TcO{sub 4}{sup -}) by SnCl{sub 2} (Moore et al., 2002). Based on these earlier promising results, an investigation was initiated into the use of apatite-type materials doped with aliovalent cations including Fe, Cu and Sn as Tc-scavengers. Synthetic Fe and Cu-doped hydroxyapatite samples were prepared by precipitation of Ca, from Ca-acetate, and P, from ammonium phosphate. The Fe and Cu were introduced as chlorides into the Ca-acetate solution. Stannous chloride was used as a reducing agent and was apparently incorporated into the crystal structures of the hydroxyapatite samples in small, as yet undetermined quantities.

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Surfactant-assisted synthesis of water-soluble and biocompatible semiconductor quantum dot micelles

Nano Letters

Fan, Hongyou F.; Leve, Erik W.; Scullin, Chessa; Gabaldon, John; Tallant, David T.; Bunge, Scott; Boyle, Tim; Wilson, Michael C.; Brinker, C.J.

We report a simple, rapid approach to synthesize water-soluble and biocompatible fluorescent quantum dot (QD) micelles by encapsulation of monodisperse, hydrophobic QDs within surfactant/lipid micelles. Analyses of UV-vis and photo luminescence spectra, along with transmission electron microscopy, indicate that the water-soluble semiconductor QD micelles are monodisperse and retain the optical properties of the original hydrophobic QDs. The QD micelles were shown to be biocompatible and exhibited little or no aggregation when taken up by cultured rat hippocampal neurons. © 2005 American Chemical Society.

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Neutron reflectivity study of lipid membranes assembled on ordered nanocomposite and nanoporous silica thin films

Langmuir

Doshi, Dhaval A.; Dattelbaum, Andrew M.; Watkins, Erik B.; Brinker, C.J.; Swanson, Basil I.; Shreve, Andrew P.; Parikh, Atul N.; Majewski, Jaroslaw

Single bilayer membranes of l-palmitoyl-2-oleoyl-sn-glycero-3- phosphocholine (POPC) were formed on ordered nanocomposite and nanoporous silica thin films by fusion of small unilamellar vesicles. The structure of these membranes was investigated using neutron reflectivity. The underlying thin films were formed by evaporation induced self-assembly to obtain periodic arrangements of silica and surfactant molecules in the nanocomposite thin films, followed by photocalcination to oxidatively remove the organics and render the films nanoporous. We show that this platform affords homogeneous and continuous bilayer membranes that have promising applications as model membranes and sensors. © 2005 American Chemical Society.

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Results 85026–85050 of 96,771
Results 85026–85050 of 96,771