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91.
Ryan F. LeBouf Bon Ki Ku Bean T. Chen David G. Frazer Jared L. Cumpston Aleksandr B. Stefaniak 《Journal of nanoparticle research》2011,13(12):7029-7039
Inhalation toxicology studies generally use the Brunauer, Emmett, and Teller (BET) gas adsorption method to measure total
surface area of particles whereas occupational exposures are more readily measured by real-time mobility-based surface areas
or active surface area measured with diffusion charger-based instruments. Three surface area measurement methods were studied:
filter-based inert gas adsorption (BET method), diffusion charging, and mobility-based methods. The goal of the project was
to investigate and develop a correlation between the measurement methods. The experimental design consisted of measuring surface
area in a series of five trials for each of two powder types, fine and ultrafine titanium dioxide with primary particle sizes
of 440 and 20 nm, respectively, and two aerosol concentrations. Diffusion charger instruments tended to underestimate the
total particle surface area measured by the BET, but were well correlated with mobility-based surface areas obtained from
a scanning mobility particle sizer. Filter-based gas adsorption methods and diffusion charging methods provide different but
valuable information on total and active surface areas of particles, respectively. Results indicate they should not be used
as predictors of one another. 相似文献
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Sergey K. Dedushenko Yurii D. Perfiliev Aleksandr A. Saprykin 《Hyperfine Interactions》2008,185(1-3):197-202
Oxidation of metallic iron by potassium superoxide leads to the formation of ferrate(V). Under room temperature this compound is unstable and instantly decomposes by disproportionation mechanism. Grinding the substance into powder accelerates the decomposition process. 相似文献
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Teodosio Luigi Alferi Giuseppe Genovese Andrea Farroni Flavio Mele Benedetto Timpone Francesco Sakhnevych Aleksandr 《Meccanica》2021,56(3):549-567
Meccanica - The characterization and reproduction of tyre behaviour for vehicle modelling is a topic of particular interest both for real-time driver in the loop simulations and for offline... 相似文献
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Vadim A. Babkin Gheorghe Cata-Danil Viacheslav M. Golovatyuk Aleksandr G. Molokanov Mihaela M. Paraipan Gennady N. Timoshenko 《Central European Journal of Physics》2010,8(4):683-688
A ridge carbon beam filter for Spreading Out the Bragg Peak (SOBP) up to 20 mm in the targeted area has been designed and experimentally tested. The instrument was constructed of Plexiglas with a density of 1.165 g/cm3 and has a “teeth” structure with a period of 2.5 mm. The design is based on a simple analytical model and detailed GEANT4 Monte Carlo simulations. In-beam test measurements were performed with a 500-MeV/u 12C beam at the Nuclotron facility of the Joint Institute for Nuclear Research (JINR) in Dubna. The filter can be used as a static device positioned in front of patients undergoing carbon therapy. 相似文献