| 1. |
- Sallee, J. B., et al.
(author)
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Southern ocean carbon and heat impact on climate
- 2023
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In: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences. - 1364-503X .- 1471-2962. ; 381:2249
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Journal article (peer-reviewed)abstract
- The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal timescales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea-ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate.This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.
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| 2. |
- Burton, B. P., et al.
(author)
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Using Ab Initio Calculations in the Calphad Environment
- 2022
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In: International Journal of Materials Research - Zeitschrift für Metallkunde. - : Walter de Gruyter GmbH. - 1862-5282 .- 2195-8556. ; 92:6, s. 514-525
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Journal article (peer-reviewed)abstract
- Methods for applying first principles (FP) calculations to CALPHAD modeling, are discussed, with emphasis on easily calculated quantities that can be used to estimate input parameters for CALPHAD optimizations. Estimations of vibrational entropies, and melting points, from chemical systematics of measured elastic constants, or via semiempirical methods based on FP calculations are reviewed. Some strategies for including higher-order (clusters larger than pairs) short range order correlations in CALPHAD calculations are considered.
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| 3. |
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| 4. |
- Corcoran, E. C., et al.
(author)
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Thermodynamic investigations of the uranium-molybdenum-oxygen system by a coupling of density functional theory and CALPHAD methodologies
- 2018
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In: Calphad. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0364-5916 .- 1873-2984. ; 63, s. 196-211
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Journal article (peer-reviewed)abstract
- This paper examines the development of a consistent thermodynamic model for the uranium (U) - molybdenum (Mo) - oxygen (0) system for incorporation into the Thermodynamics of Advanced Fuels - International Database (TAF-ID). Phase diagram data and thermodynamic properties from the literature are reviewed. Density functional theory ab initio calculations at 0 K are combined with a quasi -harmonic statistical thermodynamic model to calculate thermodynamic functions (e.g., integral Delta H-298.15K(0), S-298.15K(0), and C-p(0) (T))of the relevant ternary compounds when little or no thermodynamic literature data are available. A CALPHAD method is employed to derive a model describing the Gibbs energy functions for all the relevant ternary compounds, the liquid phase, and the gas phase of the U-Mo-O system. A consistent thermodynamic model is obtained for the Mo-U-0 system with a special emphasis placed on the oxygen rich portion of the ternary (ie., MoO2-UO2-O). Finally, supporting binary and pseudo binary diagrams (e.g., Mo-O, UO2-MoO3 and UO3-MoO3) are computed and compared to literature data.
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| 5. |
- Dupin, N., et al.
(author)
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A thermodynamic database for Ni-base superalloys
- 2001
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In: Scandinavian journal of metallurgy. - : Wiley. - 0371-0459 .- 1600-0692. ; 30:3, s. 184-192
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Journal article (peer-reviewed)abstract
- A thermodynamic database has been developed for Ni-base superalloys. Following the CALPHAD procedure, it is based on the assessment of thermodynamic behaviour of the relevant constituting sub-systems of the complex system of interest. The current database contains 7 elements: Al, Co, Cr, Ni, Ti, W, Re. The thermodynamics of the gamma and gamma' phases are modelled with a single Gibbs energy function taking into account the crystallographic relation between these two phases. The formalism of the thermodynamic models used is briefly introduced. A few phase diagrams calculated with the current database in assessed binary and ternary systems are presented. Some experiments available in higher order systems are compared with the results of calculations with the current database. The ability of extrapolation of the database is verified for solid state equilibria as well as for solidification behaviour (liquidus temperature and partition ratios). The introduction of Mo and Ta to the current database is in progress. Other elements (Nb, Fe, Zr, Hf, C, B, . . .) are planed to be introduced.
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| 6. |
- Dupin, N., et al.
(author)
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Thermodynamic re-assessment of the ternary system Al-Cr-Ni
- 2001
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In: Calphad. - 0364-5916 .- 1873-2984. ; 25:2, s. 279-298
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Journal article (peer-reviewed)abstract
- A re-assessment of the ternary system AI-Cr-Ni following Dupin's thesis work using a single Gibbs energy function for the gamma and gamma' phases is presented taking into account new experimental liquidus temperatures. The disordered bcc A2 and ordered B2 phases are also modelled with a single equation. The existence of vacancies as defects in this structure is described. The other phases are modelled as substitutional solutions, or as stoichiometric or non-stroichiometric binary compounds. The present assessment is limited to the sub system AlNi-Cr-Ni where no ternary phase exists. The parameters describing the Gibbs energy of all the assessed phases are given. Extensive comparisons between calculation and experimental data are presented.
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| 7. |
- Dupin, N., et al.
(author)
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Using first-principles results to calculate finite-temperature thermodynamic properties of the Nb-Ni mu phase in the Bragg-Williams approximation
- 2006
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In: Philosophical Magazine. - : Informa UK Limited. - 1478-6435 .- 1478-6443. ; 86:12, s. 1631-1641
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Journal article (peer-reviewed)abstract
- Results of first-principles (FP) total energy calculations for 32 different configurations of the mu phase in the binary system Nb-Ni are used in the compound energy formalism (CEF) to model finite-temperature thermodynamic properties. A comparison with Cluster Expansion Hamiltonian-Cluster Variation Method (CEH-CVM) calculations indicates that the CEF describes temperature-dependent site occupancies as well as the CEH-CVM within the temperature range of interest for applications. This suggests that the Bragg-Williams-Gorsky approximation (BWGA) used in the CEF is sufficient to describe site occupancies and thermodynamics of the mu phase. A phase diagram is calculated using the mu phase description derived in the present work together with a previous Calphad description for the other phases of this system. The FP-CEF approach significantly improves the description of the thermodynamic properties as a function of composition compared to the Calphad procedure generally used up to now.
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| 8. |
- Janier, M., et al.
(author)
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2020 European guideline on the management of syphilis
- 2021
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In: Journal of the European Academy of Dermatology and Venereology. - : Blackwell Publishing. - 0926-9959 .- 1468-3083. ; 35:1, s. 574-588
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Journal article (peer-reviewed)abstract
- The 2020 edition of the European guideline on the management of syphilis is an update of the 2014 edition.Main modifications and updates include:The ongoing epidemics of early syphilis in Europe, particularly in men who have sex with men (MSM)The development of dual treponemal and non-treponemal point-of-care (POC) testsThe progress in non-treponemal test (NTT) automatizationThe regular episodic shortage of benzathine penicillin G (BPG) in some European countriesThe exclusion of azithromycin as an alternative treatment at any stage of syphilisThe pre-exposure or immediate post-exposure prophylaxis with doxycycline in populations at high risk of acquiring syphilis.
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| 9. |
- Joubert, J. M., et al.
(author)
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Assessment of the niobium-nickel system
- 2004
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In: Calphad. - : Elsevier BV. - 0364-5916 .- 1873-2984. ; 28:3, s. 299-306
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Journal article (peer-reviewed)abstract
- A reassessment of the Nb-Ni system is proposed taking into account new experimental data. According to recent crystallographic work, the g phase has been modelled using three independent sublattices of variable occupation. This has been made possible by including experimental site fractions in the different sublattices as data for parameter optimization. A consistent set of parameters is proposed. Good agreement is obtained between calculated and experimental values for all kinds of data (thermodynamic, crystallographic and phase diagram data).
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| 10. |
- Kusoffsky, A., et al.
(author)
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On the compound energy formalism applied to fcc ordering
- 2001
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In: Calphad. - 0364-5916 .- 1873-2984. ; 25:4, s. 549-565
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Journal article (peer-reviewed)abstract
- The influence on the phase diagram and thermodynamic properties of some parameters in the Compound Energy Formalism (CEF) is studied for different simple binary and ternary cases showing fcc ordering. It is shown that the flexibility of this formalism should enable to model most real cases. Recommendations for the ternary parameters that should be set from the binary systems are made.
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