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Liquid metal Galinstan (GaInSn) is corrosive in nature against other solid metals as its base component is gallium. This study experimentally investigated the compatibility of GaInSn with eight common metals at temperatures up to 200 [degrees]C for 2000 h, including aluminum, copper, brass, ferritic and austenitic stainless steels (E-brite, SS304L, SS316L), and nickel-chromium alloys (Inconel and Hastelloy). This assessment aims to assist in design and material selection of a liquid metal magnetohy-drodynamics system that houses Galinstan for power generation by low temperature natural heat sources or industrial waste heat. Design and fabrication of this renewable power system required assurance of material compatibility with common construction and instrumentation materials. The most severe corrosion effects of GaInSn on the metal alloys were observed on aluminum, copper, and brass, which confirms the results of previously conducted studies. No obvious corrosion on stainless steel or nickel-chromium alloys were observed by this study, which reveals that stainless steel has a good resistance to attack by GaInSn up to 200 [degrees]C. Six non-metals were also evaluated, including acronitrile butadiene styrene (ABS), acrylic, nitrile rubber (Buna N), nylon, polyvinyl chloride (PVC), and Teflon, which were deemed to be compatible with GaInSn up to the temperatures tested. Key words: Galinstan corrosion, gallium corrosion, liquid metal embrittlement, liquid metal corrosion, magnetohydrodynamics. Le galinstan (GaInSn) est un metal liquide de nature corrosive comparativement a d'autres metaux solides, car il est majoritairement compose de gallium. Les presents travaux ont porte sur l'etude experimentale de la compatibilite du galinstan avec huit metaux communs a des temperatures allant jusqu'a 200 [degrees]C pendant 2 000 heures, dont l'aluminium, le cuivre, le laiton, l'acier inoxydable ferritique et l'acier inoxydable austenitique (E-Brite, SS304L, SS316L), ainsi que des alliages de nickel-chrome (Inconel et Hastelloy). Cette evaluation vise a faciliter la selection des materiaux pour la conception d'un systeme magnetohy-drodynamique a metal liquide qui comprend du galinstan en vue de produire de l'energie a partir de sources de chaleur naturelles a basse temperature ou de dechets industriels. La conception et la fabrication de ce systeme de production d'energie renouvelable ont exige que l'on s'assure de la compatibilite des composants avec les materiaux de construction et d'instrumentation courants. Les effets de corrosion les plus importants du galinstan sur les alliages metalliques ont ete observes avec l'aluminium, le cuivre et le laiton, ce qui confirme les resultats d'etudes menees anterieurement. Aucune corrosion evidente sur les alliages d'acier inoxydable ou de chrome-nickel n'a ete observee dans le cadre de cette etude, ce qui indique que l'acier inoxydable presente une bonne resistance a l'attaque par le galinstan jusqu'a 200 [degrees]C. Nous avons egalement evalue six non-metaux, dont l'acrylonitrile-butadiene-styrene (ABS), l'acrylique, le caoutchouc nitrile (Buna N), le nylon, le polychlorure de vinyle (PVC) et le Teflon, qui se sont reveles compatibles avec le galinstan jusqu'aux temperatures evaluees. [Traduit par la Redaction] Mots-cles : corrosion du galinstan, corrosion du gallium, fragilisation de metal liquide, corrosion de metal liquide, magnetohydrodynamique., Introduction Galinstan (GaInSn) is a non-toxic liquid metal, a eutectic alloy of gallium (Ga), indium (In), and tin (Sn). The composition of GaInSn was patented in 2000 and its melting [...]

Diligent preparation and effective countermeasures are critical to mitigating future influenza pandemics. The 1918 influenza pandemic, the most severe in recent history, resulted in [approximately equal to] 50 million deaths [...]

Influenza pandemics occur when novel strains of the influenza virus emerge in human populations and spread worldwide (1). There were 3 influenza pandemics in the 20th century (1918, 1957, and [...]

Amine dissolved in alcohol is one of the possible biphasic absorbents for CO 2 capture. Monoethanolamine (MEA) and methylaminoethanol (MAE) in isooctanol and 1-heptanol, respectively, were tested as absorbents by using a self-made batch mode chemisorption apparatus. CO 2 absorption vapour-liquid equilibrium (VLE) curves were obtained. Phase separation of the absorbent MEA in alcohols occurred readily upon CO 2 absorption at the absorption temperature. The CO 2 bubbling absorption tests indicated that MAE in the alcohols did not experience phase separation in the whole possible operating temperature range from ambient to 90 °C. The principle for identifying potential CO 2 phase separation absorbents is by a good match of the relative strength of the polarity of the amines with the solvent (alcohol in this study), and its change upon CO 2 absorption and/or on further temperature increase of the CO 2 loaded absorbent. The VLE curves are one of the most important properties of a CO 2 /absorbent system, based on which, some of the engineering design and operation conditions of a CO 2 absorption process can be determined. [ABSTRACT FROM AUTHOR]

In order to improve corrosion resistance of a condensing heat exchanger, a fluoropolymer, perfluoroalkoxy alkane (PFA), fine powder in 30 wt% aqueous slurry was coated on metal coupons and a coating of high quality finish was obtained. The coating was characterized by microscopy and thickness measurements. The thickness of the coating can be controlled by the number of layers used for the application of wet spray. Hot acid bath corrosion tests showed that the coated coupon possesses the highest adhesion strength and excellent corrosion resistance (1.8-6.7 × 10−3 mm/year), comparable to super alloys such as Inconel (1.1-26.2 × 10−3 mm/year) and Hastelloy (0.3-19.8 × 10−3 mm/year). A heat transfer coefficient analysis showed that across a heat transfer metal tube coated with PFA, the heat transfer resistance of the gas side film is one order of magnitude larger than the resistance from the coated layer. The developed coating could provide an alternative material solution for condensing heat exchangers used in low-grade waste heat recovery. [ABSTRACT FROM AUTHOR]

In preparing for influenza pandemics, public health agencies stockpile critical medical resources. Determining appropriate quantities and locations for such resources can be challenging, given the considerable uncertainty in the timing and severity of future pandemics. We introduce a method for optimizing stockpiles of mechanical ventilators, which are critical for treating hospitalized influenza patients in respiratory failure. As a case study, we consider the US state of Texas during mild, moderate, and severe pandemics. Optimal allocations prioritize local over central storage, even though the latter can be deployed adaptively, on the basis of real-time needs. This prioritization stems from high geographic correlations and the slightly lower treatment success assumed for centrally stockpiled ventilators. We developed our model and analysis in collaboration with academic researchers and a state public health agency and incorporated it into a Web-based decision-support tool for pandemic preparedness and response. [ABSTRACT FROM AUTHOR]

Since the first disclosure of a patent on biphasic CO 2 capture absorbent in 2005, more and more research work has been carried out worldwide looking for new biphasic systems and expanding the earlier achievements. There are two types of biphasic absorbent systems: amine dissolved in alcohol, i.e., non-aqueous system; and less soluble amines (alkanolamines or lipophilic amines, single amine or a mixture of amines) dissolved in water, i.e., aqueous system. Phase separation could happen at absorption temperature or at higher temperature, resulting in a CO 2 -rich phase and a CO 2 -lean phase. Only the CO 2 -rich phase will be regenerated, rendering a smaller regenerator and lower regeneration energy consumption. Some of the biphasic absorbent systems show lower regeneration temperatures and higher regeneration depth compared to aqueous MEA (monoethanolamine), indicating even more potential merits. In this paper, the previous R&D results and data are summarized and reviewed. Future directions for research and development are discussed. [ABSTRACT FROM AUTHOR]

Developers of direct carbon fuel cell (DCFC) technology seek to convert carbon to a pure or highly concentrated carbon dioxide stream that could ultimately be transported and sequestered. Carbon black produced by natural gas cracking processes is very pure and is therefore a candidate for use in DCFCs. In this study the performance of As received and Treated carbon blacks are compared in a planar cell configuration. At a more viable operating temperature of 750 °C, the As received carbon was found to produce a peak power density of 51 mW/cm2 at a current density of 104 mA/cm2. The performance then increased to 105 mW/cm2 at a current density of 145 mA/cm2 at 850 °C. Acid treatment of the carbon was found to improve performance of the DCFC at 750 °C by 35% (69 mW/cm2 at 160 mA/cm2) and only by 5% at 850 °C (111 mW/cm2 at 201 mA/cm2). • A commercial carbon black was used to fuel a planar, direct carbon fuel cell (DCFC). • An acid treatment method applied to the carbon black increased its wettability. • A DCFC output higher power density with Treated than with As received carbon black. [ABSTRACT FROM AUTHOR]