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Rehman A, van de Kruijs RWE, van den Beld WTE, Sturm JM, Ackermann M. Chemical Interaction of Hydrogen Radicals (H*) with Transition Metal Nitrides. J Phys Chem C Nanomater Interfaces 2023; 127:17770-17780. [PMID: 37736296 PMCID: PMC10510390 DOI: 10.1021/acs.jpcc.3c04490] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/18/2023] [Indexed: 09/23/2023]
Abstract
Transition metal nitrides (TMNs) are reported as protective coatings in reactive hydrogen environments. Although the permeation of H2 through TMN coatings is well reported, their reducibility in H* environments is less investigated. In this work, we categorize the interaction of H* with ambient exposed TiN, ZrN, HfN, VN, NbN, and TaN thin films at 700 °C into three classes. We find that in TiN and VN samples, H*-induced reduction was limited to the surface (≈ top 2 nm). Significant denitridation was observed in ZrN and HfN samples beneath the surface, along with an increase in the transition metal oxide (TMOx) fraction. Denitridation was observed in NbN and TaN samples as well, but the increase in the TMOx content was less than for ZrN and HfN. We propose a model in three steps: hydrogenation, formation of volatile species, and diffusion of subsurface atoms to the surface. We show that the interaction of H* with TiN, ZrN, HfN, VN, NbN, and TaN with partially oxidized surfaces can be explained using the preferred hydrogenation pathway (based on the work functions) and the thermodynamic driver for forming volatile species (NH3 and H2O; based on the change in Gibbs free energy).
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Affiliation(s)
- Abdul Rehman
- Industrial Focus Group XUV Optics,
MESA+ Institute for Nanotechnology, University
of Twente, Drienerlolaan 5, Enschede 7522NB, Netherlands
| | - Robbert W. E. van de Kruijs
- Industrial Focus Group XUV Optics,
MESA+ Institute for Nanotechnology, University
of Twente, Drienerlolaan 5, Enschede 7522NB, Netherlands
| | - Wesley T. E. van den Beld
- Industrial Focus Group XUV Optics,
MESA+ Institute for Nanotechnology, University
of Twente, Drienerlolaan 5, Enschede 7522NB, Netherlands
| | - Jacobus M. Sturm
- Industrial Focus Group XUV Optics,
MESA+ Institute for Nanotechnology, University
of Twente, Drienerlolaan 5, Enschede 7522NB, Netherlands
| | - Marcelo Ackermann
- Industrial Focus Group XUV Optics,
MESA+ Institute for Nanotechnology, University
of Twente, Drienerlolaan 5, Enschede 7522NB, Netherlands
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Chandrasekaran A, van de Kruijs RW, Sturm JM, Bijkerk F. Nb Texture Evolution and Interdiffusion in Nb/Si-Layered Systems. ACS Appl Mater Interfaces 2021; 13:31260-31270. [PMID: 34165281 PMCID: PMC8289241 DOI: 10.1021/acsami.1c06210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
In this paper, we present a detailed study on the microstructure evolution and interdiffusion in Nb/Si-layered systems. Interlayer formation during the early stages of growth in sputter-deposited Nb-on-Si and Si-on-Nb bilayer systems is studied in vacuo using a high-sensitivity low-energy ion-scattering technique. An asymmetric intermixing behavior is observed, where the Si-on-Nb interface is ∼2× thinner than the Nb-on-Si interface, and it is explained by the surface-energy difference between Nb and Si. During Nb-on-Si growth, the crystallization of the Nb layer occurs around 2.1 nm as-deposited Nb thickness with a strong Nb(110)-preferred orientation, which is maintained up to 3.3 nm as-deposited Nb thickness. A further increase in the Nb layer thickness above 3.3 nm results in a polycrystalline microstructure with a reduced degree of texture. High-resolution cross-sectional transmission electron microscopy imaging is performed on Nb/Si multilayers to study the effect of the Nb layer texture on interdiffusion during low-temperature annealing. Nb/Si multilayers with amorphous 2 nm Nb layers and strongly textured 3 nm thick Nb layers, with limited grain-boundary pathways for diffusion, show no observable interdiffusion during annealing at 200 °C for 8 h, whereas in a Nb/Si multilayer with polycrystalline 4 nm thick Nb layers, a ∼1 nm amorphous Nb/Si interlayer is formed at the Si-on-Nb interface during annealing.
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Chandrasekaran A, van de Kruijs RWE, Sturm JM, Zameshin AA, Bijkerk F. Nanoscale Transition Metal Thin Films: Growth Characteristics and Scaling Law for Interlayer Formation. ACS Appl Mater Interfaces 2019; 11:46311-46326. [PMID: 31729860 PMCID: PMC6909253 DOI: 10.1021/acsami.9b14414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
A comprehensive study on the growth of nanoscale transition metal-on-transition metal (TM-on-TM) systems is presented. The near room-temperature intermixing and segregation phenomena during growth are studied in vacuo using high-sensitivity low-energy ion scattering. The investigated TM-on-TM systems are classified into four types according to the observed intermixing and segregation behavior. Empirical rules are suggested to qualitatively predict the growth characteristics of any TM-on-TM system based on the atomic size difference, surface-energy difference, and enthalpy of mixing between the film and substrate atoms. An exponential trend is observed in the effective interface width as a function of the surface-energy difference between the film and substrate layers, with a subtrend based on the crystal structure of the TM layers. A semiempirical model that accurately describes the experimental data is presented. It serves as a scaling law to predict the effective interface width and the minimum film thickness required for full film coverage in TM-on-TM systems in general. The ability to predict the growth characteristics as well as the interface width for any TM-on-TM system significantly contributes to the process of finding the best material combination for a specific application, where layer growth characteristics are implicitly considered when selecting materials based on their functional properties.
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Kuznetsov DS, Yakshin AE, Sturm JM, Bijkerk F. Grazing-Incidence La/B-Based Multilayer Mirrors for 6. x nm Wavelength. J Nanosci Nanotechnol 2019; 19:585-592. [PMID: 30327073 DOI: 10.1166/jnn.2019.16476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We studied a possibility of fabricating LaN/B grazing incidence multilayer mirrors for 6.x nm radiation at a relatively large angle of incidence (AOI = 77° off-normal). LaN/B multilayers with a periodicity of 15 nm were successfully fabricated. But when stored in air for one week they showed strong deterioration of the surface due to oxidation of the topmost LaN layers, even though the multilayer was capped with a thin B film. In a series of experiments with variable LaN thickness it was found that the B protective properties depend on the thickness of the underlying LaN layer. Based on these experiments a 15 nm LaN/La/B multilayer with a passivation layer of only 0.4 nm of LaN was fabricated, which did not show any deterioration of the surface within a testing period of half a year. An initial reflectivity of 74.5% at ≈6.66 nm, AOI = 77° off-normal was achieved, which was reduced by 0.5% absolute in half a year, due to contamination of the top B layer.
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Affiliation(s)
- D S Kuznetsov
- Industrial Focus Group XUV Optics, MESA + Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
| | - A E Yakshin
- Industrial Focus Group XUV Optics, MESA + Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
| | - J M Sturm
- Industrial Focus Group XUV Optics, MESA + Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
| | - F Bijkerk
- Industrial Focus Group XUV Optics, MESA + Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
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Milov I, Makhotkin IA, Sobierajski R, Medvedev N, Lipp V, Chalupský J, Sturm JM, Tiedtke K, de Vries G, Störmer M, Siewert F, van de Kruijs R, Louis E, Jacyna I, Jurek M, Juha L, Hájková V, Vozda V, Burian T, Saksl K, Faatz B, Keitel B, Plönjes E, Schreiber S, Toleikis S, Loch R, Hermann M, Strobel S, Nienhuys HK, Gwalt G, Mey T, Enkisch H, Bijkerk F. Mechanism of single-shot damage of Ru thin films irradiated by femtosecond extreme UV free-electron laser. Opt Express 2018; 26:19665-19685. [PMID: 30114137 DOI: 10.1364/oe.26.019665] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Ruthenium is a perspective material to be used for XUV mirrors at free-electron laser facilities. Yet, it is still poorly studied in the context of ultrafast laser-matter interaction. In this work, we present single-shot damage studies of thin Ru films irradiated by femtosecond XUV free-electron laser pulses at FLASH. Ex-situ analysis of the damaged spots, performed by different types of microscopy, shows that the weakest detected damage is surface roughening. For higher fluences we observe ablation of Ru. Combined simulations using Monte-Carlo code XCASCADE(3D) and the two-temperature model reveal that the damage mechanism is photomechanical spallation, similar to the case of irradiating the target with optical lasers. The analogy with the optical damage studies enables us to explain the observed damage morphologies.
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Belsey NA, Cant DJH, Minelli C, Araujo JR, Bock B, Brüner P, Castner DG, Ceccone G, Counsell JDP, Dietrich PM, Engelhard MH, Fearn S, Galhardo CE, Kalbe H, Won Kim J, Lartundo-Rojas L, Luftman HS, Nunney TS, Pseiner J, Smith EF, Spampinato V, Sturm JM, Thomas AG, Treacy JP, Veith L, Wagstaffe M, Wang H, Wang M, Wang YC, Werner W, Yang L, Shard AG. Versailles Project on Advanced Materials and Standards Interlaboratory Study on Measuring the Thickness and Chemistry of Nanoparticle Coatings Using XPS and LEIS. J Phys Chem C Nanomater Interfaces 2016; 120:24070-24079. [PMID: 27818719 PMCID: PMC5093768 DOI: 10.1021/acs.jpcc.6b06713] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) inter-laboratory study on the measurement of the shell thickness and chemistry of nanoparticle coatings. Peptide-coated gold particles were supplied to laboratories in two forms: a colloidal suspension in pure water and; particles dried onto a silicon wafer. Participants prepared and analyzed these samples using either X-ray photoelectron spectroscopy (XPS) or low energy ion scattering (LEIS). Careful data analysis revealed some significant sources of discrepancy, particularly for XPS. Degradation during transportation, storage or sample preparation resulted in a variability in thickness of 53 %. The calculation method chosen by XPS participants contributed a variability of 67 %. However, variability of 12 % was achieved for the samples deposited using a single method and by choosing photoelectron peaks that were not adversely affected by instrumental transmission effects. The study identified a need for more consistency in instrumental transmission functions and relative sensitivity factors, since this contributed a variability of 33 %. The results from the LEIS participants were more consistent, with variability of less than 10 % in thickness and this is mostly due to a common method of data analysis. The calculation was performed using a model developed for uniform, flat films and some participants employed a correction factor to account for the sample geometry, which appears warranted based upon a simulation of LEIS data from one of the participants and comparison to the XPS results.
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Affiliation(s)
| | - David J. H. Cant
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW,
UK
| | - Caterina Minelli
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW,
UK
| | - Joyce R. Araujo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia
(INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das
Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Bernd Bock
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | | | - David G. Castner
- National ESCA and Surface Analysis Center for Biomedical
Problems, Departments of Bioengineering and Chemical Engineering, University of Washington,
Seattle, WA 98195-1653, USA
| | - Giacomo Ceccone
- European Commission Joint Research Centre, Institute for Health
and Consumer Protection, Nanobiosciences Unit, Via E. Fermi 2749, 21027 Ispra, Italy
| | | | - Paul M. Dietrich
- BAM Federal Institute for Materials Research and Testing (BAM
6.1), Unter den Eichen 44-46, D-12203 Berlin, Germany
| | - Mark H. Engelhard
- Pacific Northwest National Laboratory, EMSL, Richland, WA 99352,
USA
| | - Sarah Fearn
- Department of Materials, Imperial College London, South
Kensington Campus, London SW7 2AZ, UK
| | - Carlos E. Galhardo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia
(INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das
Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Henryk Kalbe
- Kratos Analytical Ltd., Wharfside, Trafford Wharf Road,
Manchester M17 1GP, UK
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science, 267
Gajeong-ro, Daejeon 34113, Korea
| | - Luis Lartundo-Rojas
- Instituto Politécnico Nacional, Centro de Nanociencias y
Micro y Nanotecnologías, UPALM, Zacatenco, México D.F. CP. 07738,
México
| | - Henry S. Luftman
- Surface Analysis Facility, Lehigh University, 7 Asa Drive,
Bethlehem, PA 18015. USA
| | - Tim S. Nunney
- Thermo Fisher Scientific, Unit 24, The Birches Industrial
Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Johannes Pseiner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr
8-10, A 1040 Vienna, Austria
| | - Emily F. Smith
- Nanoscale and Microscale Research Centre, School of Chemistry,
University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Valentina Spampinato
- National ESCA and Surface Analysis Center for Biomedical
Problems, Departments of Bioengineering and Chemical Engineering, University of Washington,
Seattle, WA 98195-1653, USA
| | - Jacobus M. Sturm
- Industrial Focus Group XUV Optics, MESA+ Institute for
Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, the Netherlands
| | - Andrew G. Thomas
- School of Materials and Photon Science Institute, University of
Manchester, Manchester, M13 9PL, UK
| | - Jon P.W. Treacy
- Thermo Fisher Scientific, Unit 24, The Birches Industrial
Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Lothar Veith
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | - Michael Wagstaffe
- School of Materials and Photon Science Institute, University of
Manchester, Manchester, M13 9PL, UK
| | - Hai Wang
- National Institute of Metrology, Beijing 100029, P. R.
China
| | - Meiling Wang
- National Institute of Metrology, Beijing 100029, P. R.
China
| | | | - Wolfgang Werner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr
8-10, A 1040 Vienna, Austria
| | - Li Yang
- Department of Chemistry, Xi'an-Jiaotong Liverpool University,
Suzhou, China
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7
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Belsey NA, Cant DJH, Minelli C, Araujo JR, Bock B, Brüner P, Castner DG, Ceccone G, Counsell JDP, Dietrich PM, Engelhard MH, Fearn S, Galhardo CE, Kalbe H, Won Kim J, Lartundo-Rojas L, Luftman HS, Nunney TS, Pseiner J, Smith EF, Spampinato V, Sturm JM, Thomas AG, Treacy JPW, Veith L, Wagstaffe M, Wang H, Wang M, Wang YC, Werner W, Yang L, Shard AG. Versailles Project on Advanced Materials and Standards Interlaboratory Study on Measuring the Thickness and Chemistry of Nanoparticle Coatings Using XPS and LEIS. J Phys Chem C Nanomater Interfaces 2016; 120:24070-24079. [PMID: 27818719 DOI: 10.1021/acs.jpcc.6b09412] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) inter-laboratory study on the measurement of the shell thickness and chemistry of nanoparticle coatings. Peptide-coated gold particles were supplied to laboratories in two forms: a colloidal suspension in pure water and; particles dried onto a silicon wafer. Participants prepared and analyzed these samples using either X-ray photoelectron spectroscopy (XPS) or low energy ion scattering (LEIS). Careful data analysis revealed some significant sources of discrepancy, particularly for XPS. Degradation during transportation, storage or sample preparation resulted in a variability in thickness of 53 %. The calculation method chosen by XPS participants contributed a variability of 67 %. However, variability of 12 % was achieved for the samples deposited using a single method and by choosing photoelectron peaks that were not adversely affected by instrumental transmission effects. The study identified a need for more consistency in instrumental transmission functions and relative sensitivity factors, since this contributed a variability of 33 %. The results from the LEIS participants were more consistent, with variability of less than 10 % in thickness and this is mostly due to a common method of data analysis. The calculation was performed using a model developed for uniform, flat films and some participants employed a correction factor to account for the sample geometry, which appears warranted based upon a simulation of LEIS data from one of the participants and comparison to the XPS results.
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Affiliation(s)
- Natalie A Belsey
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW, UK
| | - David J H Cant
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW, UK
| | - Caterina Minelli
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW, UK
| | - Joyce R Araujo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Bernd Bock
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | | | - David G Castner
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Seattle, WA 98195-1653, USA
| | - Giacomo Ceccone
- European Commission Joint Research Centre, Institute for Health and Consumer Protection, Nanobiosciences Unit, Via E. Fermi 2749, 21027 Ispra, Italy
| | | | - Paul M Dietrich
- BAM Federal Institute for Materials Research and Testing (BAM 6.1), Unter den Eichen 44-46, D-12203 Berlin, Germany
| | - Mark H Engelhard
- Pacific Northwest National Laboratory, EMSL, Richland, WA 99352, USA
| | - Sarah Fearn
- Department of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Carlos E Galhardo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Henryk Kalbe
- Kratos Analytical Ltd., Wharfside, Trafford Wharf Road, Manchester M17 1GP, UK
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science, 267 Gajeong-ro, Daejeon 34113, Korea
| | - Luis Lartundo-Rojas
- Instituto Politécnico Nacional, Centro de Nanociencias y Micro y Nanotecnologías, UPALM, Zacatenco, México D.F. CP. 07738, México
| | - Henry S Luftman
- Surface Analysis Facility, Lehigh University, 7 Asa Drive, Bethlehem, PA 18015. USA
| | - Tim S Nunney
- Thermo Fisher Scientific, Unit 24, The Birches Industrial Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Johannes Pseiner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr 8-10, A 1040 Vienna, Austria
| | - Emily F Smith
- Nanoscale and Microscale Research Centre, School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Valentina Spampinato
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Seattle, WA 98195-1653, USA
| | - Jacobus M Sturm
- Industrial Focus Group XUV Optics, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, the Netherlands
| | - Andrew G Thomas
- School of Materials and Photon Science Institute, University of Manchester, Manchester, M13 9PL, UK
| | - Jon P W Treacy
- Thermo Fisher Scientific, Unit 24, The Birches Industrial Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Lothar Veith
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | - Michael Wagstaffe
- School of Materials and Photon Science Institute, University of Manchester, Manchester, M13 9PL, UK
| | - Hai Wang
- National Institute of Metrology, Beijing 100029, P. R. China
| | - Meiling Wang
- National Institute of Metrology, Beijing 100029, P. R. China
| | | | - Wolfgang Werner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr 8-10, A 1040 Vienna, Austria
| | - Li Yang
- Department of Chemistry, Xi'an-Jiaotong Liverpool University, Suzhou, China
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Senf F, Bijkerk F, Eggenstein F, Gwalt G, Huang Q, Kruijs R, Kutz O, Lemke S, Louis E, Mertin M, Packe I, Rudolph I, Schäfers F, Siewert F, Sokolov A, Sturm JM, Waberski C, Wang Z, Wolf J, Zeschke T, Erko A. Highly efficient blazed grating with multilayer coating for tender X-ray energies. Opt Express 2016; 24:13220-13230. [PMID: 27410339 DOI: 10.1364/oe.24.013220] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
For photon energies of 1 - 5 keV, blazed gratings with multilayer coating are ideally suited for the suppression of stray and higher orders light in grating monochromators. We developed and characterized a blazed 2000 lines/mm grating coated with a 20 period Cr/C- multilayer. The multilayer d-spacing of 7.3 nm has been adapted to the line distance of 500 nm and the blaze angle of 0.84° in order to provide highest efficiency in the photon energy range between 1.5 keV and 3 keV. Efficiency of the multilayer grating as well as the reflectance of a witness multilayer which were coated simultaneously have been measured. An efficiency of 35% was measured at 2 keV while a maximum efficiency of 55% was achieved at 4 keV. In addition, a strong suppression of higher orders was observed which makes blazed multilayer gratings a favorable dispersing element also for the low X-ray energy range.
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Kuznetsov DS, Yakshin AE, Sturm JM, van de Kruijs RWE, Louis E, Bijkerk F. High-reflectance La/B-based multilayer mirror for 6.x nm wavelength. Opt Lett 2015; 40:3778-3781. [PMID: 26274658 DOI: 10.1364/ol.40.003778] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report a hybrid thin-film deposition procedure to significantly enhance the reflectivity of La/B-based multilayer structures. This is of relevance for applications of multilayer optics at 6.7-nm wavelength and beyond. Such multilayers showed a reflectance of 64.1% at 6.65 nm measured at 1.5-degrees off-normal incidence at PTB (BESSY-II). This was achieved by a special scheme of La passivation. The La layer was nitridated to avoid formation of the optically unfavorable LaBx compound at the B-on-La interface. To avoid the also undesired BN formation at the La-on-B interface, a time-dosed nitridation at the initial stage was applied. This research revealed a good potential for further increase in the reflectivity of multilayer structures at 6.7 nm.
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Sturm JM, Göbke D, Kuhlenbeck H, Döbler J, Reinhardt U, Ganduglia-Pirovano MV, Sauer J, Freund HJ. Partial oxidation of methanol on well-ordered V(2)O(5)(001)/Au(111) thin films. Phys Chem Chem Phys 2009; 11:3290-9. [PMID: 19370226 DOI: 10.1039/b822384j] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The partial oxidation of methanol to formaldehyde on well-ordered thin V(2)O(5)(001) films supported on Au(111) was studied. Temperature-programmed desorption shows that bulk-terminated surfaces are not reactive, whereas reduced surfaces produce formaldehyde. Formaldehyde desorption occurs between 400 K and 550 K, without evidence for reaction products other than formaldehyde and water. Scanning tunnelling microscopy shows that methanol forms methoxy groups on vanadyl oxygen vacancies. If methanol is adsorbed at low temperature, the available adsorption sites are only partly covered with methoxy groups after warming up to room temperature, whereas prolonged methanol dosing at room temperature leads to full coverage. In order to explain these findings we present a model that essentially comprises recombination of methoxy and hydrogen to methanol in competition with the reaction of two surface hydroxyl groups to form water.
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Affiliation(s)
- J M Sturm
- Fritz Haber Institute of the Max Planck Society, Chemical Physics Department, Faradayweg 4-6, 14195, Berlin, Germany
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Cano N, Sturm JM, Meijer AJ, El-Mir MY, Novaretti R, Reynier JP, Leverve XM. Effect of chronic renal failure with metabolic acidosis on alanine metabolism in isolated liver cells. Clin Nutr 2004; 23:317-24. [PMID: 15158294 DOI: 10.1016/j.clnu.2003.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2003] [Accepted: 07/25/2003] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Decreased ureagenesis and gluconeogenesis from alanine have been reported during chronic renal failure in rat. This study addressed the respective roles of plasma-membrane transport and intracellular metabolism in these abnormalities of alanine pathways. METHODS In hepatocytes isolated from uremic and control rats, we investigated: (1) the influence of uremia on gluconeogenesis and ureagenesis during incubations with alanine; (2) the kinetics of alanine plasma-membrane transport; (3) the relationships between intracellular alanine concentrations and its metabolism. Plasma-membrane alanine transport was assessed after addition of alanine (2 mM) by measuring its intracellular accumulation from 0 to 10 min, in the presence of a transaminase inhibitor. Alanine metabolism was studied in perifused hepatocytes by measuring intracellular alanine concentration together with urea, glucose and lactate production in the presence of increasing concentrations of alanine (0-8 mM). RESULTS Uremic rats showed decreased plasma bicarbonate. Uremia induced (P<0.05) a decrease in both gluconeogenesis (36%) and ureagenesis (22%). Alanine plasma-membrane transport decreased by 20% during uremia. During perifusions, uremia induced a 30-40% decrease in urea, glucose, and lactate production without modifying intracellular alanine concentration. CONCLUSIONS In uremic rats with acidosis, hepatocyte alanine utilization was impaired at both plasma-membrane transport and intracellular transamination steps.
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Affiliation(s)
- N Cano
- Service d'Hépatogastroentérologie et de Nutrition, Clinique Résidence du Parc, Rue Gaston Berger, 13362, Marseille Cedex 10, France.
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Cappleman MW, Thompson RJ, DeRemer-Sullivan PA, King AA, Sturm JM. Effectiveness of a home based early intervention program with infants of adolescent mothers. Child Psychiatry Hum Dev 2001; 13:55-65. [PMID: 7168963 DOI: 10.1007/bf00709982] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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13
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Arvieux C, Létoublon C, Bouchard F, Pasquier D, Delecour T, Barnoud D, Penillon S, Barnoud R, Sturm JM, Hodaj H, Borel E, Naud G, Pirenne J, Zarski JP. [Liver transplantation with a graft taken from a heart transplant patient who was brain-dead]. Ann Chir 2000; 125:376-9. [PMID: 10900741 DOI: 10.1016/s0003-3944(00)00210-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The shortage of organ donors has led to progressive softening of selection criteria for organ donation. We report on hepatic transplantation in a 55-year-old woman with primary biliary cirrhosis, whose donor was a 50-year-old heart transplant recipient who became brain stem dead, due to cerebral bleeding 8 months after transplantation. An orthotopic liver transplantation was performed. The postoperative course was uneventful and the recipient was alive and had normal liver function after a 42-month follow-up. Analysis of the literature included ethical consideration, potential hepatotoxic effects of immunosuppressive drugs and modification of the graft immunogenicity. It confirms that transplanted patients should not be a priori excluded from organ donation.
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Affiliation(s)
- C Arvieux
- Service de chirurgie générale et digestive, Grenoble, France
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Sturm JM, Maurizi-Balzan J, Forêt M, Cordonnier D. [Dialysis in octagenarians: search for mortality risk factors. Consecutive series of 30 patients]. Presse Med 1998; 27:748-52. [PMID: 9767896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
OBJECTIVE To assess renal replacement therapy in elderly subjects aged 80 years or more in order to depict factors predicting mortality. PATIENTS AND METHODS We retrospectively studied 30 consecutive patients at the time of starting dialysis from January 1995 to August 1995 and followed this population though March 1996. RESULTS Only past ischemic heart disease and emergency situations were emphasized as predictor factors of mortality risk. No difference according to mortality between hemodialysis and peritoneal dialysis subgroups was found. CONCLUSION Excepting usual contraindications for uremic populations, no objective medical criteria are at present time sufficient for excluding chronic renal replacement therapy in very old patients. However, its effect on quality of life must be estimated in order to determine the cost/benefit ratio.
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Affiliation(s)
- J M Sturm
- Service de Néphrologie, Hôpital A. Michallon, CHU de Grenoble
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Sturm JM, Janbon B, Pinel N, Brion JP, Cordonnier D. [Post-streptococcal acute glomerulonephritis in an 84-year old male patient with biclonal dysglobulinemia]. Presse Med 1993; 22:1233. [PMID: 8248048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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Thompson RJ, Gothard DC, Sturm JM, Rogister SH. Identification audiometry: component effectiveness and relationship of hearing status to developmental functioning with four-year-olds. J Aud Res 1979; 19:209-15. [PMID: 553925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Kuiper CJ, Sturm JM. [Anaphrodisia in gilts and sows(author's transl)]. Tijdschr Diergeneeskd 1975; 100:824-35. [PMID: 1172636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The economy of pig breeding and rearing farms is determined mainly by the fertility of the animals. Anaphrodisia causes a considerable disturbance of the fertility. This has a direct effect on the number of litters born per sow per year and thus on the economic results. On the basis of several years of experience at the research station and the production unit of Varkensonderzoekcentrum Nieuw-Dalland the clinical symptoms in gilts and sows are described. Gilts should normally have come into oestrus at the age of about 8 months, and on a well-managed farm about 80% of the sows should come into oestrus within 10 days of weaning, provided that weaning takes place at 5 to 6 weeks. Different forms of anaphrodisia are described, based on the findings of post mortem examinations. These show that in 65-75% of the anaphrodisiac animals the ovaries were insufficiently active. In 20% of the animals that had not shown signs of oestrus, ovulation had in fact taken place. The causes of anaphrodisia must be sought in a disturbance of the hypothalamo-hypophysial ovarian system, in which genetic and health factors play an important role, besides housing and management (insluding feeding). A good keeping of records of sows is indispensable in the solving of the anaphrodisia problem on farms, and this hinges also on an analysis of the farm management and on the power of observation of the farmer. Finally, hormonal therapy is discussed, a distinction being made between breeding and rearing farms.
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