Search Results - "Hamann, W"

Determination of photoelectrochemical water oxidation intermediates on haematite electrode surfaces using operando infrared spectroscopy by Zandi, Omid, Hamann, Thomas W.

“…Semiconductor electrodes capable of using solar photons to drive water-splitting reactions, such as haematite (α-Fe 2 O 3 ), have been the subject of…”
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Early magnetic B-type stars: X-ray emission and wind properties by Oskinova, L. M., Todt, H., Ignace, R., Brown, J. C., Cassinelli, J. P., Hamann, W.-R.

“…We present a comprehensive study of X-ray emission by, and wind properties of, massive magnetic early B-type stars. Dedicated XMM-Newton observations were…”
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Enhanced Water Splitting Efficiency Through Selective Surface State Removal by Zandi, Omid, Hamann, Thomas W

“…Hematite (α-Fe2O3) thin film electrodes prepared by atomic layer deposition (ALD) were employed to photocatalytically oxidize water under 1 sun illumination…”
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High-resolution X-ray spectroscopy of bright O-type stars by Oskinova, L. M., Feldmeier, A., Hamann, W.-R.

“…Archival X-ray spectra of the four prominent single, non-magnetic O stars ζ Pup, ζ Ori, ξ Per and ζ Oph, obtained in high resolution with Chandra HETGS/MEG…”
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A COORDINATED X-RAY AND OPTICAL CAMPAIGN OF THE NEAREST MASSIVE ECLIPSING BINARY, δ ORIONIS Aa. IV. A MULTIWAVELENGTH, NON-LTE SPECTROSCOPIC ANALYSIS by Shenar, T., Oskinova, L., Hamann, W.-R., Corcoran, M. F., Moffat, A. F. J., Pablo, H., Richardson, N. D., Waldron, W. L., Huenemoerder, D. P., Maíz Apellániz, J., Nichols, J. S., Todt, H., Nazé, Y., Hoffman, J. L., Pollock, A. M. T., Negueruela, I.

“…ABSTRACT Eclipsing systems of massive stars allow one to explore the properties of their components in great detail. We perform a multi-wavelength, non-LTE…”
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Stellar winds and mass loss from extreme helium stars by Jeffery, C. S., Hamann, W.-R.

“…Extreme helium stars are very rare low-mass supergiants in a late stage of evolution. They are probably contracting to become white dwarfs following a violent…”
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Performance Enhancement and Limitations of Cobalt Bipyridyl Redox Shuttles in Dye-Sensitized Solar Cells by Klahr, Benjamin M, Hamann, Thomas W

“…A series of one-electron outersphere cobalt bipyridyl redox couples were used as redox shuttles in dye-sensitized solar cells (DSSCs). Atomic layer deposition…”
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Enhanced Charge Separation and Collection in High-Performance Electrodeposited Hematite Films by Zandi, Omid, Schon, Abraham R, Hajibabaei, Hamed, Hamann, Thomas W

“…Hematite electrodes with variable morphologies were prepared via a simple electrodeposition (ED) method. The photoelectrochemical (PEC) properties of planar…”
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Searching for a magnetic field in Wolf–Rayet stars using FORS 2 spectropolarimetry by Hubrig, S., Scholz, K., Hamann, W.-R., Schöller, M., Ignace, R., Ilyin, I., Gayley, K. G., Oskinova, L. M.

“…To investigate if magnetic fields are present in Wolf–Rayet stars, we selected a few stars in the Galaxy and one in the Large Magellanic Cloud (LMC). We…”
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Impact of Ultrathin C60 on Perovskite Photovoltaic Devices by Liu, Dianyi, Wang, Qiong, Traverse, Christopher J, Yang, Chenchen, Young, Margaret, Kuttipillai, Padmanaban S, Lunt, Sophia Y, Hamann, Thomas W, Lunt, Richard R

“…Halide perovskite solar cells have seen dramatic progress in performance over the past several years. Certified efficiencies of inverted structure (p-i-n)…”
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PROBING WOLF-RAYET WINDS: CHANDRA/HETG X-RAY SPECTRA OF WR 6 by Huenemoerder, David P., Gayley, K. G., Hamann, W.-R., Ignace, R., Nichols, J. S., Oskinova, L., Pollock, A. M. T., Schulz, N. S., Shenar, T.

“…ABSTRACT With a deep Chandra/HETGS exposure of WR 6, we have resolved emission lines whose profiles show that the X-rays originate from a uniformly expanding…”
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Measurements and Modeling of Recombination from Nanoparticle TiO2 Electrodes by Ondersma, Jesse W, Hamann, Thomas W

“…Electron-transfer reactions from nanoparticle TiO2 films to outer-sphere redox shuttles were investigated. Steady-state dark current density versus applied…”
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Direct Deposition of Crystalline Ta3N5 Thin Films on FTO for PEC Water Splitting by Hajibabaei, Hamed, Little, Daniel J, Pandey, Ayush, Wang, Dunwei, Mi, Zetian, Hamann, Thomas W

“…Tantalum nitride is a promising photoanode material for solar water splitting, but further study and practical use are constrained by the harsh conditions of…”
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On the Binary Nature of Massive Blue Hypergiants: High-resolution X-Ray Spectroscopy Suggests That Cyg OB2 12 is a Colliding Wind Binary by Oskinova, L. M., Huenemoerder, D. P., Hamann, W.-R., Shenar, T., Sander, A. A. C., Ignace, R., Todt, H., Hainich, R.

“…The blue hypergiant Cyg OB2 12 (B3Ia+) is a representative member of the class of very massive stars in a poorly understood evolutionary stage. We obtained its…”
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EXPANSION OF HYDROGEN-POOR KNOTS IN THE BORN-AGAIN PLANETARY NEBULAE A30 AND A78 by Fang, X, Guerrero, M A, Marquez-Lugo, R A, Toala, J A, Arthur, S J, Chu, Y-H, Blair, W P, Gruendl, R A, Hamann, W-R, Oskinova, L M, Todt, H

“…We analyze the expansion of hydrogen-poor knots and filaments in the born-again planetary nebulae A30 and A78 based on Hubble Space Telescope (HST) images…”
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One of the most massive stars in the Galaxy may have formed in isolation by Oskinova, L. M., Steinke, M., Hamann, W.-R., Sander, A., Todt, H., Liermann, A.

“…Very massive stars, 100 times heavier than the sun, are rare. It is not yet known whether such stars can form in isolation or only in star clusters. The answer…”
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New Architectures for Dye-Sensitized Solar Cells by Martinson, Alex B. F., Hamann, Thomas W., Pellin, Michael J., Hupp, Joseph T.

“…Modern dye‐sensitized solar cell (DSSC) technology was built upon nanoparticle wide bandgap semiconductor photoanodes. While versatile and robust, the sintered…”
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Discovery of two new Galactic candidate luminous blue variables with Wide-field Infrared Survey Explorer by Gvaramadze, V. V., Kniazev, A. Y., Miroshnichenko, A. S., Berdnikov, L. N., Langer, N., Stringfellow,  G. S., Todt, H., Hamann, W.-R., Grebel, E. K., Buckley, D., Crause, L., Crawford, S., Gulbis, A., Hettlage, C., Hooper, E., Husser, T.-O., Kotze, P., Loaring, N., Nordsieck, K. H., O'Donoghue, D., Pickering, T., Potter, S., Romero Colmenero, E., Vaisanen, P., Williams, T., Wolf, M., Reichart, D. E., Ivarsen, K. M., Haislip, J. B., Nysewander, M. C., LaCluyze, A. P.

“…We report the discovery of two new Galactic candidate luminous blue variable (LBV) stars via detection of circular shells (typical of confirmed and candidate…”
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Potential-sensing electrochemical atomic force microscopy for in operando analysis of water-splitting catalysts and interfaces by Nellist, Michael R., Laskowski, Forrest A. L., Qiu, Jingjing, Hajibabaei, Hamed, Sivula, Kevin, Hamann, Thomas W., Boettcher, Shannon W.

“…Heterogeneous electrochemical phenomena, such as (photo)electrochemical water splitting to generate hydrogen using semiconductors and/or electrocatalysts, are…”
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Ionization and Star Formation in the Giant H ii Region SMC-N66 by Geist, E., Gallagher, J. S., Kotulla, R., Oskinova, L., Hamann, W.-R., Ramachandran, V., Sabbi, E., Smith, L., Kniazev, A., Nota, A., Rickard, M. J.

“…Abstract The NGC 346 young stellar system and associated N66 giant H ii region in the Small Magellanic Cloud are the nearest example of a massive star-forming…”
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