| 1. |
- Wang, J., et al.
(författare)
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Final report of the CCQM-K145 : Toxic and essential elements in bovine liver
- 2020
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Ingår i: Metrologia. - : IOP Publishing Ltd. - 0026-1394 .- 1681-7575. ; 57:1 A
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Tidskriftsartikel (refereegranskat)abstract
- Liver plays a major role in metabolism and acts as a source of energy for the body by storing glycogen. With the growing interest and investigation in the biological effects in recent years, it is important and necessary to develop accurate and comparable analytical methods for elements in bio-samples. It has, however, been 10 years since the tissue sample (bovine liver) of CCQM-K49 key comparison. The purpose of CCQM-K145 is to ensure the comparable and traceable measurement results for essential and toxic elements such as P, S, Zn, Mn, Ni, Mo, Sr, Cr, Co, Pb, As and Hg in bovine liver among NMIs and other designated measurement bodies worldwide. The comparison was agreed by IAWG as 6th IAWG Benchmarking Exercise with Zn and Ni as exemplary elements at the meeting in Korea in the early October 2016. The results of CCQM-K145 are expected to cover the measurement capability and support CMCs claiming for inorganic elements in the similar biological tissue materials and food samples. 30 NMIs and DIs registered in CCQM-K145. With respect to the methodology, a variety of techniques such as IDMS, ICP-OES, ICP-MS(non-ID), AAS and NAA were adopted by the participants. For Zn, Ni, Sr, Pb and Hg measurements, most participants chose ID-ICP-MS method, which showed the better performance in terms of consistency and reliability of the measurement results. In aspect of the traceability for the measurement results in CCQM-K145, most participants used their own (in house) CRMs or other NMI's CRMs to guarantee trace to SI unit. Most participants used similar matrix CRMs for quality control or method validation. Base on different statistic way to calculate the reference mass fraction values and associated uncertainties for each measurand, removal of the suspected extreme values, and discussion at the IAWG meetings, the median values are proposed as the KCRV for Zn, Ni, Mn, Mo, Cr, Pb and Hg; the arithmetic mean values are proposed as the KCRV for P, S, Sr, Co and As. In general, the performances of the majority of CCQM-K145 participants are very good, illustrating their measurement capabilities for Zn, Ni, P, S, Mn, Mo, Sr, Cr, As, Co, Pb and Hg in a complex biological tissue matrix. Bovine liver contains many kinds of nutrients and microelements, it can be regarded as a typical representative material of biological tissue and food. In CCQM-K145, the analytes involved alkali metals and transition elements, metalloids/semi-metals and non metals with a range of mass fraction from mg/g to μg/kg. CCQM-K145 also tested the ability of NMIs/DIs to determine elements that were easy to be lost and polluted, and interfered significantly. The chemical pretreatment methods of samples used in the comparison is suitable for general food and biological matrix samples. A variety of measurement methods used in the comparison represent the main instrumental technology for elemental analysis. Therefore, for supporting CMC claim, CCQM-K145 is readily applicable to measurement of more elements in a wide range of biological materials (including liquids and solids) and meat products. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
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| 2. |
- Wang, C., et al.
(författare)
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Experimental investigation of hydrochar injection to the blast furnace
- 2019
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Ingår i: AISTech - Iron and Steel Technology Conference Proceedings. - : Association for Iron and Steel Technology, AISTECH. ; , s. 531-536
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Konferensbidrag (refereegranskat)abstract
- For an integrated steel plant, the blast furnace (BF) is the most energy intensive process unit in which coke and pulverized coal (PC) are used as reducing agents and energy carriers, leading to huge amount of fossil CO2 emission. Recent years, the steel industry has been putting much effort to reduce CO2 emissions especially for BFs. Biofuel is considered as one shortterm solution for CO2 emission reduction especially via the tuyere injection into BFs to replace PC. Much work has been carried out to inject wood charcoal in BFs due to the fact that the wood charcoal has the similar properties as PC [1]. However, the availability of forestry wood and high price of wood charcoal limit the charcoal’s utilization in BFs. So far, the charcoal injection is only realized in small scale BFs in Brazil.
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| 3. |
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| 4. |
- De Moor, K., et al.
(författare)
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Influence of high ambient illuminance and display luminance on readability and subjective preference
- 2015
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - Bellingham, WA, USA : SPIE. - 9781628414844
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Konferensbidrag (refereegranskat)abstract
- Many devices, such as tablets, smartphones, notebooks, fixed and portable navigation systems are used on a (nearly) daily basis, both in in- and outdoor environments. It is often argued that contextual factors, such as the ambient illuminance in relation to characteristics of the display (e.g., surface treatment, screen reflectance, display luminance...) may have a strong influence on the use of such devices and corresponding user experiences. However, the current understanding of these influence factors is still rather limited. In this work, we therefore focus in particular on the impact of lighting and display luminance on readability, visual performance, subjective experience and preference. A controlled lab study (N=18) with a within-subjects design was performed to evaluate two car displays (one glossy and one matte display) in conditions that simulate bright outdoor lighting conditions. Four ambient luminance levels and three display luminance settings were combined into 7 experimental conditions. More concretely, we investigated for each display: (1) whether and how readability and visual performance varied with the different combinations of ambient luminance and display luminance and (2) whether and how they influenced the subjective experience (through self-reported valence, annoyance, visual fatigue) and preference. The results indicate a limited, yet negative influence of increased ambient luminance and reduced contrast on visual performance and readability for both displays. Similarly, we found that the self-reported valence decreases and annoyance and visual fatigue increase as the contrast ratio decreases and ambient luminance increases. Overall, the impact is clearer for the matte display than for the glossy display.
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| 5. |
- Fellinger, Joris, et al.
(författare)
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Tungsten based divertor development for Wendelstein 7-X
- 2023
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Ingår i: Nuclear Materials and Energy. - 2352-1791. ; 37
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Tidskriftsartikel (refereegranskat)abstract
- Wendelstein 7-X, the world’s largest superconducting stellarator in Greifswald (Germany), started plasma experiments with a water-cooled plasma-facing wall in 2022, allowing for long pulse operation. In parallel, a project was launched in 2021 to develop a W based divertor, replacing the current CFC divertor, to demonstrate plasma performance of a stellarator with a reactor relevant plasma facing materials with low tritium retention. The project consists of two tasks: Based on experience from the previous experimental campaigns and improved physics modelling, the geometry of the plasma-facing surface of the divertor and baffles is optimized to prevent overloads and to improve exhaust. In parallel, the manufacturing technology for a W based target module is qualified. This paper gives a status update of project. It focusses on the conceptual design of a W based target module, the manufacturing technology and its qualification, which is conducted in the framework of the EUROfusion funded WPDIV program. A flat tile design in which a target module is made of a single target element is pursued. The technology must allow for moderate curvatures of the plasma-facing surface to follow the magnetic field lines. The target element is designed for steady state heat loads of 10 MW/m2 (as for the CFC divertor). Target modules of a similar size and weight as for the CFC divertor are assumed (approx. < 0.25 m2 and < 60 kg) using the existing water cooling infrastructure providing 5 l/s and roughly maximum 15 bar pressure drop per module. The main technology under qualification is based on a CuCrZr heat sink made either by additive manufacturing using laser powder bed fusion (LPBF) or by uniaxial diffusion welding of pre-machined forged CuCrZr plates. After heat treatment, the plasma-facing side of the heat sink is covered by W or if feasible by the more ductile WNiFe, preferably by coating or alternatively by hot isostatic pressing W based tiles with a soft OFE-Cu interlayer. Last step is a final machining of the plasma-exposed surface and the interfaces to the water supply lines and supports to correct manufacturing deformations.
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| 6. |
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| 7. |
- Kang, W., et al.
(författare)
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Chemical and sensory impacts of Accentuated Cut Edges (ACE) grape must polyphenol extraction technique on shiraz wines
- 2020
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Ingår i: Foods. - : MDPI AG. - 2304-8158. ; 9:8
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Tidskriftsartikel (refereegranskat)abstract
- Accentuated Cut Edges (ACE) is a recently developed grape must extraction technique, which mechanically breaks grape skins into small fragments but maintains seed integrity. This study was the first to elucidate the effect of ACE on Shiraz wine's basic chemical composition, colour, phenolic compounds, polysaccharides and sensory profiles. A further aim was to investigate any potential influence provided by ACE on the pre-fermentation water addition to must. ACE did not visually affect Shiraz wine colour, but significantly enhanced the concentration of tannin and total phenolics. Wine polysaccharide concentration was mainly increased in response to the maceration time rather than the ACE technique. ACE appeared to increase the earthy/dusty flavour, possibly due to the different precursors released by the greater skin breakage. The pre-fermentation addition of the water diluted the wine aromas, flavours and astringency profiles. However, combining the ACE technique with water addition enhanced the wine textural quality by increasing the intensities of the crucial astringent wine quality sub-qualities, adhesive and graininess. Furthermore, insights into the chemical factors influencing the astringency sensations were provided in this study. This research indicates that wine producers may use ACE with pre-fermentation water dilution to reduce the wine alcohol level but maintain important textural components. © 2020 by the authors.
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| 8. |
- Roziková, M., et al.
(författare)
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Electrolytic conductivity at pure water level final report
- 2020
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Ingår i: Metrologia. - : IOP Publishing Ltd. - 0026-1394 .- 1681-7575. ; 58:1 A
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Tidskriftsartikel (refereegranskat)abstract
- Electrolytic conductivity in aqueous solutions is one of the most common electrochemical measurement techniques in industry. Since it is sensitive to the amount content of dissolved ions in a solution, a limiting value for conductivity is a clear and simple quality criterium for the ionic purity of water. The relevant measuring range for pure water applications is roughly between 0.055 μS cm-1 (ultrapure water) and 150 μS cm-1 at 25 °C. For instance, the European, Japanese and United States (USP) Pharmacopoeia have specified the requirements for purified water, highly purified water and water for injection for pharmaceutical use based on conductiv-ity. Sectors that also use conductivity limits for water purity are electrical power production, food industry, electronic industry and analytical laboratories. At low conductivity levels it is not feasible to circulate water samples for comparison measure-ments, since the conductivity value is instable due to inevitable ionic contamination. The main contamination results from carbon dioxide in ambient air that dissolves in water and builds H3O+ and hydrogen carbonate ions. The contribution of these ions to conductivity is around 1 μS cm-1. Hence, it is impossible to provide stable samples having usable uncertainties in the conductivity range of interest. EURAMET 1271, performed in 2013, was the first successful comparison measurement of pure water conductivity. In the meanwhile, more NMIs, the majority of which is situated in Europe, have built measurement capabilities in the pure water range. EURAMRET 1271 covered a measurement range up to 50 μS cm-1, whereas more and more customers request conductivity cell calibration in the range up to 150 μS cm-1. Consequently, this comparison intends to extend the measurement range and to enable more NMIs to get support for potential CMCs. Therefore, this comparison is additionally intended being a supplementary CCQM comparison. A commercial conductivity measurement meter, including a conductivity measurement cell, was used for the comparison in a Round-Robin scheme. The devices were provided by PTB and were sent from one institute to another. Each institute had to measure the conductivity of a reference solution using the conductivity meter. The reference solution could either be pure water or a measurement standard solution that was reasonably stable in the range of interest. In the first scheme, the cell had to be integrated in a closed pure water flow though system to minimize impurification by CO2. An adequate fixture for this setup was provided by PTB. In the second scheme, the cell was immersed into the measurement standard solution under tem-perature-controlled conditions. Essentially, the institutes had to report the conductivity values indicated by the conductivity meter and the conductivity reference value assigned to the water in the flow though system or that of the measurement standard solution, respectively. The co-ordinating institute calculated adjusted cell constants for the cell from the reported values, which were used to calculate linking conductivities, the actual quantities to be finally compared. The results showed good equivalence in all conductivity ranges, with only a few inconsistent values. Adequate comparison reference values are suggested that can serve to calculate robust degrees of equivalences for the participants usable to support respective CMC claims.
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| 9. |
- Steele, A., et al.
(författare)
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Organic synthesis on Mars by electrochemical reduction of CO2
- 2018
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Ingår i: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 4:10
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Tidskriftsartikel (refereegranskat)abstract
- The sources and nature of organic carbon on Mars have been a subject of intense research. Steele et al. (2012) showed that 10 martian meteorites contain macromolecular carbon phases contained within pyroxene- and olivine-hosted melt inclusions. Here, we show that martian meteorites Tissint, Nakhla, and NWA 1950 have an inventory of organic carbon species associated with fluid-mineral reactions that are remarkably consistent with those detected by the Mars Science Laboratory (MSL) mission. We advance the hypothesis that interactions among spinel-group minerals, sulfides, and a brine enable the electrochemical reduction of aqueous CO2 to organic molecules. Although documented here in martian samples, a similar process likely occurs wherever igneous rocks containing spinel-group minerals and/or sulfides encounter brines.
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| 10. |
- Van Der Wee, Marlies, et al.
(författare)
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Techno-economic evaluation of FTTH migration for a network provider : Comparison of NG-AON and TWDM-PON
- 2013
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Ingår i: Asia Communications and Photonics Conference, ACP. - Washington, D.C. : OSA - The Optical Society. - 9781557529893
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Konferensbidrag (refereegranskat)abstract
- This paper studies the business case of migration from legacy FTTH networks like active star Ethernet and GPON towards NG-AON and TWDM-PON for a network provider, evaluating its techno-economic viability and suggesting possible improvements.
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