Zobrazeno 1 - 10
of 27
pro vyhledávání: '"Jan Kehres"'
Autor:
Elisabetta M. Fiordaliso, Irek Sharafutdinov, Hudson W. P. Carvalho, Jan Kehres, Jan-D. Grunwaldt, Ib Chorkendorff, Christian D. Damsgaard
Publikováno v:
Science and Technology of Advanced Materials, Vol 20, Iss 1, Pp 521-531 (2019)
The CO2 hydrogenation to methanol is efficiently catalyzed at ambient pressure by nanodispersed intermetallic GaPd2/SiO2 catalysts prepared by incipient wetness impregnation. Here we optimize the catalyst in terms of metal content and reduction tempe
Externí odkaz:
https://doaj.org/article/537bf157aa044ad090c4fbbb8a8daeb4
Autor:
Ulrik L. Olsen, Mads G. Laursen, Piotr S. Mazurek, Jan Kehres, Lars P. Mikkelsen, Anne L. Skov, Henning F. Poulsen
Publikováno v:
Olsen, U L, Laursen, M G, Mazurek, P S, Kehres, J, Mikkelsen, L P, Skov, A L & Poulsen, H F 2022, ' Multiscale characterisation of strains in semicrystalline polymers ', Journal of Polymer Research, vol. 29, no. 5, 175 . https://doi.org/10.1007/s10965-022-03014-5
A nondestructive probe for mapping elastic strains within polymers would be an asset for materials engineering: for validation of mechanical models and for understanding damage nucleation. As a step towards this aim we demonstrate an X-ray wide angle
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::88ca9c1153f21cab87e53803b89bad84
https://doi.org/10.1007/s10965-022-03014-5
https://doi.org/10.1007/s10965-022-03014-5
Publikováno v:
Silvestre, C M, Hemmingsen, J H, Dreier, E S, Kehres, J & Hansen, O 2019, ' Laser ablation of high-aspect-ratio hole arrays in tungsten for X-ray applications ', Microelectronic Engineering, vol. 209, pp. 60-65 . https://doi.org/10.1016/j.mee.2019.03.007
Periodic two-dimensional tungsten X-ray optical gratings were fabricated using a combination of pico-second laser ablation and wet chemical etch. A 200 μm thick cold-rolled sheet of tungsten (99.97%) was used as base material for the fabrication of
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::20a29e46838493954940d072bd161ae0
https://doi.org/10.1016/j.mee.2019.03.007
https://doi.org/10.1016/j.mee.2019.03.007
Autor:
Doniyor Jumanazarov, Jakeoung Koo, Jan Kehres, Henning F. Poulsen, Ulrik L. Olsen, Mihai Iovea
Publikováno v:
Materials Characterization
Jumanazarov, D, Koo, J, Kehres, J, Poulsen, H F, Olsen, U L & Iovea, M 2022, ' Material classification from sparse spectral X-ray CT using vectorial total variation based on L infinity norm ', Materials Characterization, vol. 187, 111864 . https://doi.org/10.1016/j.matchar.2022.111864
Jumanazarov, D, Koo, J, Kehres, J, Poulsen, H F, Olsen, U L & Iovea, M 2022, ' Material classification from sparse spectral X-ray CT using vectorial total variation based on L infinity norm ', Materials Characterization, vol. 187, 111864 . https://doi.org/10.1016/j.matchar.2022.111864
The development of energy resolving photon counting detectors (PCD) has paved the way to spectral X-ray Computed Tomography (CT), with which one can simultaneously extract the energy dependence of a material's linear attenuation coefficient (LAC). Sp
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4859132e520eb9d4b901fdf0a4568835
https://doi.org/10.1016/j.matchar.2022.111864
https://doi.org/10.1016/j.matchar.2022.111864
Publikováno v:
Journal of Synchrotron Radiation. 25:1650-1657
Timepix3 (256 × 256 pixels with a pitch of 55 µm) is a hybrid-pixel-detector readout chip that implements a data-driven architecture and is capable of simultaneous time-of-arrival (ToA) and energy (ToT: time-over-threshold) measurements. The ToA in
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a91a077dd47bddfe79be430ebc7aae9a
https://doi.org/10.1107/s1600577518013838
https://doi.org/10.1107/s1600577518013838
Publikováno v:
Busi, M, Kehres, J, Khalil, M & Olsen, U L 2019, Effective atomic number and electron density determination using spectral X-ray CT . in A A, J A G & M E G (eds), Anomaly Detection and Imaging with X-Rays (ADIX) IV . vol. 10999, 1099903, SPIE-International Society for Optical Engineering, Proceedings of SPIE-The International Society for Optical Engineering, SPIE Defense + Commercial Sensing 2019, Baltimore, Maryland, United States, 14/04/2019 . https://doi.org/10.1117/12.2519851
We present Spectral X-ray Computed Tomography (SCT) estimations of material properties directly from energy-dependent measurements of linear attenuation coefficients (LAC). X-ray Computed Tomography (CT) is commonly utilized to characterize the inter
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ffacc705ed116a1d2a2fa207a88503a5
https://orbit.dtu.dk/en/publications/2180d531-2387-4c7b-8ad8-48b9bd7f2b89
https://orbit.dtu.dk/en/publications/2180d531-2387-4c7b-8ad8-48b9bd7f2b89
Autor:
Jan Kehres, Christian Danvad Damsgaard, J.-D. Grunwaldt, Elisabetta Maria Fiordaliso, Irek Sharafutdinov, Hudson Wallace Pereira de Carvalho, Ib Chorkendorff
Publikováno v:
Fiordaliso, E M, Sharafutdinov, I, Carvalho, H W P, Kehres, J, Grunwaldt, J-D, Chorkendorff, I & Damsgaard, C D 2019, ' Evolution of intermetallic GaPd 2 /SiO 2 catalyst and optimization for methanol synthesis at ambient pressure ', Science and Technology of Advanced Materials, vol. 20, no. 1, pp. 521-531 . https://doi.org/10.1080/14686996.2019.1603886
Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
Science and Technology of Advanced Materials, Vol 20, Iss 1, Pp 521-531 (2019)
Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
Science and Technology of Advanced Materials, Vol 20, Iss 1, Pp 521-531 (2019)
The CO2 hydrogenation to methanol is efficiently catalyzed at ambient pressure by nanodispersed intermetallic GaPd2/SiO2 catalysts prepared by incipient wetness impregnation. Here we optimize the catalyst in terms of metal content and reduction tempe
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d8bb9d41d58a4017dfd6a14f4dbbfb63
https://orbit.dtu.dk/en/publications/4137e0c7-e80d-4fa6-87c0-3da21fe0717e
https://orbit.dtu.dk/en/publications/4137e0c7-e80d-4fa6-87c0-3da21fe0717e
Autor:
Martin Nielsen, Ana Diaz, Thomas Pedersen, Jane Hvolbæk Nielsen, Jens Wenzel Andreasen, Jan Kehres, Federico Masini, Ole Hansen, Ib Chorkendorff
Publikováno v:
Journal of Synchrotron Radiation
Kehres, J, Pedersen, T, Masini, F, Andreasen, J W, Nielsen, M M, Diaz, A, Nielsen, J H, Hansen, O & Chorkendorff, I 2016, ' Novel micro-reactor flow cell for investigation of model catalysts using in situ grazing-incidence X-ray scattering ', Journal of Synchrotron Radiation, vol. 23, no. 2, pp. 455-463 . https://doi.org/10.1107/S1600577516001387
Kehres, J, Pedersen, T, Masini, F, Andreasen, J W, Nielsen, M M, Diaz, A, Nielsen, J H, Hansen, O & Chorkendorff, I 2016, ' Novel micro-reactor flow cell for investigation of model catalysts using in situ grazing-incidence X-ray scattering ', Journal of Synchrotron Radiation, vol. 23, no. 2, pp. 455-463 . https://doi.org/10.1107/S1600577516001387
The design and performance of a novel micro-reactor in situ flow cell permitting investigation of model catalysts with grazing-incidence small- and wide-angle X-ray scattering is presented.
The design, fabrication and performance of a novel and
The design, fabrication and performance of a novel and
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::29fb52d5daeb9344fde8d96fe7a5643c
https://doi.org/10.1107/s1600577516001387
https://doi.org/10.1107/s1600577516001387
Autor:
Jan Kehres, J. Jakubek, Chantal Silvestre, Ulrik Lund Olsen, Ole Hansen, Daniel Turecek, E.S. Dreier, Robert Feidenhans'l, Mohamad Khalil, Jens H. Hemmingsen
Publikováno v:
Dreier, E S, Silvestre, C, Kehres, J, Turecek, D, Khalil, M, Hemmingsen, J H, Hansen, O, Jakubek, J, Feidenhans'l, R & Olsen, U L 2020, ' Single-shot, omni-directional x-ray scattering imaging with a laboratory source and single-photon localization ', Optics Letters, vol. 45, no. 4, pp. 1021-1024 . https://doi.org/10.1364/OL.381420
Dreier, E S, Silvestre, C, Kehres, J, Turecek, D, Khalil, M, Hemmingsen, J H, Hansen, O, Jakubek, J, Feidenhans'l, R K & Olsen, U L 2020, ' Single-shot, omni-directional x-ray scattering imaging with a laboratory source and single-photon localization ', Optics Letters, vol. 45, no. 4, pp. 1021-1024 . https://doi.org/10.1364/ol.381420
Dreier, E S, Silvestre, C, Kehres, J, Turecek, D, Khalil, M, Hemmingsen, J H, Hansen, O, Jakubek, J, Feidenhans'l, R K & Olsen, U L 2020, ' Single-shot, omni-directional x-ray scattering imaging with a laboratory source and single-photon localization ', Optics Letters, vol. 45, no. 4, pp. 1021-1024 . https://doi.org/10.1364/ol.381420
Omni-directional, ultra-small-angle x-ray scattering imaging provides a method to measure the orientation of micro-structures without having to resolve them. In this letter, we use single-photon localization with the Timepix3 chip to demonstrate, to
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::558dd810f9d7996b7c7fe691ce636ea2
https://doi.org/10.1364/ol.381420
https://doi.org/10.1364/ol.381420
Autor:
Kristoffer Haldrup, Erik Knudsen, Ulrik Lund Olsen, Jeppe Revall Frisvad, Mohamad Khalil, E.S. Dreier, Jan Kehres, Matteo Busi
Publikováno v:
Busi, M, Olsen, U L, Knudsen, E B, Frisvad, J R, Kehres, J & Dreier, E S 2018, ' Simulation tools for scattering corrections in spectrally resolved X-ray Computed Tomography using McXtrace ', Optical Engineering, vol. 57, no. 3, 037105 . https://doi.org/10.1117/1.OE.57.3.037105
Spectral computed tomography is an emerging imaging method that involves using recently developed energy discriminating photon-counting detectors (PCDs). This technique enables measurements at isolated high-energy ranges, in which the dominating unde
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9a7b231ecf3d4f2a5295aa3bcae2c515
https://orbit.dtu.dk/en/publications/a15d7252-ccf8-443e-8cdf-8b80d978cd91
https://orbit.dtu.dk/en/publications/a15d7252-ccf8-443e-8cdf-8b80d978cd91