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Full-Text Articles in Physical Sciences and Mathematics

The Immersion Mode Ice Nucleation Behavior Of Mineral Dusts: A Comparison Of Different Pure And Surface Modified Dusts, S. Augustin-Bauditz, H. Wex, S. Kanter, M. Ebert, D. Niedermeier, F. Stolz, A. Prager, F. Stratmann Oct 2014

The Immersion Mode Ice Nucleation Behavior Of Mineral Dusts: A Comparison Of Different Pure And Surface Modified Dusts, S. Augustin-Bauditz, H. Wex, S. Kanter, M. Ebert, D. Niedermeier, F. Stolz, A. Prager, F. Stratmann

Michigan Tech Publications

In this study we present results from immersion freezing experiments with size-segregated mineral dust particles. Besides two already existing data sets for Arizona Test Dust (ATD), and Fluka kaolinite, we show two new data sets for illite-NX, which consists mainly of illite, a clay mineral, and feldspar, a common crustal material. The experiments were carried out with the Leipzig Aerosol Cloud Interaction Simulator. After comparing the different dust samples, it became obvious that the freezing ability was positively correlated with the K-feldspar content. Furthermore, a comparison of the composition of the ATD, illite-NX, and feldspar samples suggests that within the …


A Semi-Lagrangian View Of Ozone Production Tendency In North American Outflow In The Summers Of 2009 And 2010, B. Zhang, R. C. Owen, J A Perlinger, A. Kumar, S. Wu, M. Val Martin, L. Kramer, D. Helmig, R. E. Honrath Mar 2014

A Semi-Lagrangian View Of Ozone Production Tendency In North American Outflow In The Summers Of 2009 And 2010, B. Zhang, R. C. Owen, J A Perlinger, A. Kumar, S. Wu, M. Val Martin, L. Kramer, D. Helmig, R. E. Honrath

Michigan Tech Publications

The Pico Mountain Observatory, located at 2225 m a.s.l. in the Azores Islands, was established in 2001 to observe long-range transport from North America to the central North Atlantic. In previous research conducted at the observatory, ozone enhancement (> 55 ppbv) in North American outflows was observed, and efficient ozone production in these outflows was postulated. This study is focused on determining the causes for high d[O3] / d[CO] values (~1 ppbv ppbv−1) observed in the summers of 2009 and 2010. The folded retroplume technique, developed by Owen and Honrath (2009), was applied to combine upwind FLEXPART transport …


Surface Effects On Critical Dimensions Of Ferromagnetic Nanoparticles, Vartika Chaudhary Jan 2014

Surface Effects On Critical Dimensions Of Ferromagnetic Nanoparticles, Vartika Chaudhary

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This work studies surface effects on the critical dimensions of ferromagnetic nanoparticles. Iron nanoparticles with different mean diameters from 5.9 nm to 21.4 nm used in this research were prepared by thermal decomposition of iron pentacarbonyl in the presence of oleic acid/octyl ether at Cambridge University, United Kingdom. Heating response of these ferromagnetic nanoparticles suspended in water were measured experimentally during which same amount of iron nanoparticles and di-ionized water were irradiated by an alternating magnetic field and the increase in temperature of these samples was measured. Heating performance of nanoparticles was described in terms of Specific Absorption Rate (SAR) …


Thermal Properties Of Magnetic Nanoparticles In External Ac Magnetic Field, Anna Beata Lukawska Jan 2014

Thermal Properties Of Magnetic Nanoparticles In External Ac Magnetic Field, Anna Beata Lukawska

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This work studies thermal properties of magnetic nanoparticles in an external ac magnetic field. Dried iron and cobalt nanoparticles were prepared by thermal decomposition of iron pentacarbonyl (Fe(CO)5) and dicobalt octacarbonyl (Co2(CO)8), triscobalt nona(carbonyl)chloride (Co3(CO)9Cl), or tetracaobalt dodecacarbonyl (Co4(CO)12) [1]. The samples had different mean diameters: 5.6 - 21.4 nm for iron and 6.5 - 19.4 nm for cobalt. Each sample was exposed to ac magnetic field and the increase in temperature of the sample was measured. Results were analyzed to find the critical diameters for the transitions from multi-domain to single-domain and from single-domain to superparamagnetic regime. The nanoparticles …


Thin Film Growth Of Dielectric Materials By Pulsed Laser Deposition, Jason Christopher Anders Jan 2014

Thin Film Growth Of Dielectric Materials By Pulsed Laser Deposition, Jason Christopher Anders

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Thin films of SryCa1-yZr1-xTixO3 (SCZT) with x = 0.8, y = 0.01, CaHf1-xTixO3 (CHT) with x = 0.8, and xBiScO3 - (1-x) BaTiO3 with x = 0.36 (BSBT(36/64)) showing a high permittivity are useful both in capacitor applications. These dielectric thin films with a SrRuO3 (SRO) conductive bottom electrodes were prepared by using pulsed laser deposition on <100< La0.3Sr0.7Al0.65Ta0.35O3 (LSAT) single crystal substrates. In a search of optimal conditions to achieve epitaxially grown SCZT, CHT, …


Ultraviolet Rayleigh Scatter Imaging For Spatial Temperature Profiles In Atmospheric Microdischarges, James E. Caplinger Jan 2014

Ultraviolet Rayleigh Scatter Imaging For Spatial Temperature Profiles In Atmospheric Microdischarges, James E. Caplinger

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Spatially resolved temperature measurements within a microdischarge in atmospheric pressure air have been conducted using Rayleigh scattering of a pulsed ultraviolet laser. Scattering intensity images were used to generate a radial profile of translational temperature, with the analysis based on the ideal gas inverse relationship of temperature and gas density. Rayleigh scattering results were compared to standard optical emission spectral analyses of N2(C3Πu - B3Πg) bands, where the calculated rotational temperatures from emission were in reasonable agreement with the Rayleigh translational temperature profiles.


Curie Temperature Measurement Of Ferromagnetic Nanoparticles By Using Calorimetry, Xing Zhao Jan 2014

Curie Temperature Measurement Of Ferromagnetic Nanoparticles By Using Calorimetry, Xing Zhao

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This Thesis studies the relationship between diameter (size) of ferromagnetic nanoparticles and Curie temperature. Iron nanoparticles with different diameters from 5.9 nm to 21.4 nm were prepared by thermal decomposition of iron pentacarbonyl in the presence of oleic acid/octyl ether at Cambridge University, United Kingdom. Heating response of these ferromagnetic nanoparticles suspended in water were measured experimentally during which the same amount of iron nanoparticles and di-ionized water were subjected to an alternating magnetic field and the increase in temperature of these samples was measured. Heating performance of nanoparticles was described by Specific Absorption Rate (SAR). Heating and cooling rate …


Chemical Analysis Of Exhaled Breath By Means Of Terahertz Rotational Spectroscopy, Tianle Guo Jan 2014

Chemical Analysis Of Exhaled Breath By Means Of Terahertz Rotational Spectroscopy, Tianle Guo

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Terahertz spectroscopy, due to the high sensitivity and specificity that it affords, has been incorporated in many fields to aid in the chemical analysis of gases. One potential application is to detect bio-markers in human breath for early diagnosis. Our current aim of our research is to establish a relationship between several chemicals and the glucose levels from human exhaled breath. 20 chemical including Acetone, Carbon monoxide (CO), Methanol were studied. Volunteers' breath samples were processed through a pre-concentration system before being injected into the spectrometer. Initially, a commercial preconcentration system, Entech 7100A, was used. However, due to the limitations …