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Yidan An, Tianshu Ma, Xiaofeng Li
Published: 5 May 2021
by Wiley
Solar RRL; doi:10.1002/solr.202100199

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, Ajay D. Surwade, Prajakta J. Rajput,
Published: 1 May 2021
Journal of Molecular Liquids, Volume 329; doi:10.1016/j.molliq.2021.115546

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, Consuelo Carli, Giuseppe Cannistraro, Jose Pascoa, Shivesh Sharma
International Journal of Heat and Mass Transfer, Volume 170, pp 120983-120983; doi:10.1016/j.ijheatmasstransfer.2021.120983

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Ronald P. White,
The Journal of Physical Chemistry B, Volume 125, pp 4221-4231; doi:10.1021/acs.jpcb.1c01620

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David Hess, Veronika Dockalova, Piia Kokkonen, David Bednar, Jiri Damborsky, , ,
Published: 1 April 2021
Chem, Volume 7, pp 1066-1079; doi:10.1016/j.chempr.2021.02.011

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, Daniel L. Eldridge, Daniel A. Stolper
Published: 1 March 2021
Geochimica et Cosmochimica Acta, Volume 297, pp 233-275; doi:10.1016/j.gca.2020.10.008

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, Pierre Bouilhol, Oscar Laurent, Linda Marko, Jean-François Moyen
Published: 1 March 2021
Lithos, Volume 384-385; doi:10.1016/j.lithos.2020.105938

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Minliang Lai, Teng Lei, Ye Zhang, Jianbo Jin, Julian A. Steele,
MRS Bulletin, Volume 46, pp 310-316; doi:10.1557/s43577-021-00047-x

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Yuan Zhang, Erren Yao, Zhen Tian, , Ke Yang
Published: 25 February 2021
Applied Thermal Engineering, Volume 185; doi:10.1016/j.applthermaleng.2020.116421

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Aylecia S. Lattimer, Steven R. Cranmer
Published: 25 January 2021
by ArXiv
Abstract:
Radiation contributes to the acceleration of large-scale flows in various astrophysical environments because of the strong opacity in spectral lines. Quantification of the associated force is crucial to understanding these line-driven flows, and a large number of lines (due to the full set of elements and ionization stages) must be taken into account. Here we provide new calculations of the dimensionless line strengths and associated opacity-dependent force multipliers for an updated list of approximately 4.5 million spectral lines compiled from the NIST, CHIANTI, CMFGEN, and TOPbase databases. To maintain generality of application to different environments, we assume local thermodynamic equilibrium, illumination by a Planck function, and the Sobolev approximation. We compute the line forces in a two-dimensional grid of temperatures (i.e., values between 5,200 and 70,000 K) and densities (varying over 11 orders of magnitude). Historically, the force multiplier function has been described by a power-law function of optical depth. We revisit this assumption by fitting alternative functions that include a saturation to a constant value (Gayley's $\bar{Q}$ parameter) in the optically-thin limit. This alternate form is a better fit than the power-law form, and we use it to calculate example mass-loss rates for massive main-sequence stars. Because the power-law force multiplier does not continue to arbitrarily small optical depths, we find a sharp decrease, or quenching, of line-driven winds for stars with effective temperatures less than about 15,000 K.
Lluís Jofre,
Progress in Energy and Combustion Science, Volume 82; doi:10.1016/j.pecs.2020.100877

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Jongseong Park, Sekwang Yoon, Se-Young Oh, Yoori Kim,
Published: 1 January 2021
Energy, Volume 214; doi:10.1016/j.energy.2020.118844

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, , , Qiushi Guan
Published: 1 December 2020
Geochimica et Cosmochimica Acta, Volume 291, pp 62-78; doi:10.1016/j.gca.2019.12.031

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Ho Seok Park
Published: 23 November 2020
ECS Meeting Abstracts, pp 599-599; doi:10.1149/ma2020-023599mtgabs

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Published: 1 November 2020
Scripta Materialia, Volume 188, pp 37-43; doi:10.1016/j.scriptamat.2020.06.060

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, Julia E. Hammer, Alan Whittington, Daniel R. Neuville
Published: 28 October 2020
Frontiers in Earth Science, Volume 8; doi:10.3389/feart.2020.607972

Abstract:
Editorial on the Research TopicResearch Topic Crystal Nucleation and Growth in Magmatic Suspensions The differentiation, rheology and transport of magmas are strongly influenced by crystallization (nucleation and growth). Nucleation and crystal growth in a batch of magma evolve through time in response to changing environmental conditions, i.e., T, P, and fO2. Investigations on naturally formed igneous rocks, combined with experiments where these environmental conditions can be controlled, are necessary to decipher, reconstruct and model the solidification of magmas. New advances continue to be made in both analytical techniques and experimental methods, with crystallization under conditions of strong disequilibrium being a particularly active area of experimental research. A host of difficulties confronts experimental studies of crystallization (nucleation, growth, and textural maturation), due to the high melting points, high degrees of chemical reactivity, and high redox sensitivities of natural (Fe-bearing) silicate liquids. These difficulties are compounded when the systems are investigated at elevated pressure or contain a high concentration of dissolved H2O. Frequently, solidification experiments are evaluated only post-quench; hence, the effect of a thermodynamic driving force (sensible cooling or decompression, if H2O-saturated) and kinetic limitations on the evolution of nucleation, crystal growth, and textures is observed mainly ex situ. The in situ observation requires relaxation of one or more of these constraints, but unlocks the opportunity to study environmental controls on individual phase appearance (or suppression), maturation of crystal populations, and overall transformation kinetics. This thematic issue contains five contributions to the study of magma crystallization. They share a reliance upon experimental data but differ in the application of in situ and ex situ methods, theoretical formulations, and the analysis of well-constrained natural volcanic samples. With Crystallization Kinetics of Alkali Feldspar in Peralkaline Rhyolitic Melts: Implications for Pantelleria Volcano, Arzilli et al. perform ‘classic’ ex situ isobaric cooling experiments at controlled fO2 and various H2O concentrations. In this manner, they evaluate the kinetic crystallization of alkali feldspars in peralkaline rhyolitic magma over wide ranges in pressure and undercooling. This data-rich contribution complements analogous studies on granite and granodiorite liquids by Fenn (1977) and Swanson (1977), quantifying the significant lag time between the imposition of a driving force for crystallization and the onset of crystallization. In The Onset and Solidification Path of a Basaltic Melt by in situ Differential Scanning Calorimetry (DSC) and ex situ Investigations, Giuliani et al. combine DSC to pinpoint the onset of crystallization in natural basalt (at ambient conditions) with electron microscopy-based textural analysis of run products. A strength of the DSC technique is the opportunity to precisely resolve transformation kinetics. They report that an increase in cooling rate by three orders of magnitude suppresses the timing of the onset of crystallization by two orders of magnitude. They further estimate the effects of cooling rate on the nucleation of spinel, plagioclase, melilite, and clinopyroxene, estimating also their growth rates. DSC thermal signals unveil that crystallization proceeds mainly by “pulses,” that can be correlated with kinks in the final crystal size distribution (CSD). In their Disequilibrium Rheology and Crystallization Kinetics of Basalts and Implications for the Phlegrean Volcanic District, Kolzenburg et al., confront the study of crystallization kinetics with an equally novel and pragmatic in situ approach combined with ex situ crystal morphology observations. Via particle suspension rheology models, they determine the temperatures of crystallization onset and lockup (i.e., the “cutoff” when flow ceases to occur) for a basaltic magma. Their results are broadly consistent with the observation of Giuliani et al. about the onset of crystallization; also, they find a decrease of ∼100 K in cutoff temperature with a 10-fold increase in cooling rate. Interestingly, although shearing has been shown to enhance crystal nucleation (Kouchi et al., 1986; Vona and Romano, 2013; Kolzenburg et al., 2018), the overall rate of solidification at 0.2 K/min still lags behind equilibrium solidification (assessed via thermodynamic modeling) until nominal undercooling of ∼40 K. In Theoretical Models of Decompression-Induced Plagioclase Nucleation and Growth in Hydrated Silica-Rich Melts, Mollard et al. access fundamental theoretical constructs for the basis of their treatment of crystal nucleation and growth. First, they back-solve the classical nucleation theory (Volmer and Weber, 1926) to obtain the crystal-liquid surface energy by the plagioclase formation during experimental decompression of H2O-saturated haplotonalite. Modifications to the classical nucleation theory, particularly regarding nucleus roughness and shape, are considered. Analysis of compositional gradients in the vicinity of plagioclase crystals underpins their determination of the CaO-in-liquid diffusion coefficient. Using the new DCaO, they model the growth of plagioclase crystals as a diffusion-controlled process at moderate undercooling. In her review paper, Crystal Size Distribution (CSD) Analysis of Volcanic Samples: Advances and Challenges, Cashman summarizes the early application of textural analysis as a means of understanding the crystallization processes in different contexts (i.e., industry, experimental petrology labs, and in natural environments). CSD theory owes its interpretive power to the special case of steady-state conditions, allowing to predict the interplay between nucleation rate, growth rate, and characteristic crystal size. When the steady-state...
Accounts of Chemical Research, Volume 53, pp 2816-2827; doi:10.1021/acs.accounts.0c00444

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Published: 15 October 2020
Energies, Volume 13; doi:10.3390/en13205366

Abstract:
Besides the widely applied hydropower, wind farms and solar energy, biomass and municipal and industrial waste are increasingly becoming important sources of renewable energy. Nevertheless, fouling, slagging and corrosion associated with the combustion processes of these renewable sources are costly and threaten the long-term operation of power plants. During a high-temperature biomass combustion, alkali metals in the biomass fuel and the ash fusion behavior are the two major contributors to slagging. Ash deposits on superheater tubes that reduce thermal efficiency are often composed of complex combinations of sulfates and chlorides of Ca, Mg, Na, and K. However, thermodynamic databases involving all the sulfates and chlorides that would favor a better understanding and control of the problems in combustion processes related to fouling, slagging and corrosion are not complete. In the present work, thermodynamic properties including solubility limits of some phases and phase mixtures in the K2SO4-(Mg,Ca)SO4 system were reviewed and experimentally investigated. Based on the new and revised thermochemical data, binary phase diagrams of the K2SO4-CaSO4 and K2SO4-MgSO4 systems above 400 °C, which are of interest in the combustion processes of renewable-energy power plants, were optimized.
Published: 1 October 2020
Additive Manufacturing, Volume 35; doi:10.1016/j.addma.2020.101395

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Irving Granet, Jorge Luis Alvarado, Maurice Bluestein
Published: 17 September 2020
Thermodynamics and Heat Power pp 201-258; doi:10.1201/9780429299629-5

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Shyang Maw Lim, Sina Kazemi Bakhshmand, Clemens Biet, Mihai Mihaescu
Published: 15 September 2020
SAE Technical Paper Series; doi:10.4271/2020-01-2225

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Randall D. Manteufel, Amir Karimi
2013 ASEE Annual Conference & Exposition Proceedings pp 23.746.1-23.746.18; doi:10.18260/1-2--19760

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Robert Ryan
2001 Annual Conference Proceedings pp 6.337.1-6.337.9; doi:10.18260/1-2--9085

The publisher has not yet granted permission to display this abstract.
Published: 27 May 2020
Thermoelectric Materials; doi:10.1515/9783110596526

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Published: 6 May 2020
Materials, Volume 13; doi:10.3390/ma13092151

Abstract:
The Kauzmann temperature TK is a lower limit of glass transition temperature, and is known as the ideal thermodynamic glass transition temperature. A supercooled liquid will condense into glass before TK. Studying the ideal glass transition temperature is beneficial to understanding the essence of glass transition in glass-forming liquids. The Kauzmann temperature TK values are predicted in 38 kinds of glass-forming liquids. In order to acquire the accurate predicted TK by using a new deduced equation, we obtained the best fitting parameters of the deduced equation with the high coefficient of determination (R2 = 0.966). In addition, the coefficients of two reported relations are replaced by the best fitting parameters to obtain the accurate predicted TK, which makes the R2 values increase from 0.685 and 0.861 to 0.970 and 0.969, respectively. Three relations with the best fitting parameters are applied to obtain the accurate predicted TK values.
Sonia Caleor-Barney, William F. Paxton, Pablo Ortiz, Mahendra Kumar Sunkara
ECS Meeting Abstracts, pp 1770-1770; doi:10.1149/ma2020-01391770mtgabs

The publisher has not yet granted permission to display this abstract.
, Carlos Garcia Vargas, Jinshu Tian, Libor Kovarik, Nicholas R. Jaegers, János Szanyi, Yong Wang
Published: 7 April 2020
Abstract:
We show for the first time that single positively-charged Rh atoms on ceria, prepared via high-temperature atom trapping synthesis, are the highly active species for (CO+NO) reaction both under dry and wet, industrial conditions. This provides a direct link between organometallic homogeneous Rh(I) complexes capable of catalyzing dry (CO+NO) reaction and supported Rh single atoms, the latter being much more active than their homogeneous analogues. Decreasing the Rh loading from to 0.1 wt% leads to a catalyst with uniform Rh ions on the surface of ceria, which is very active (full NO conversion >120 ⁰C, TOF per Rh atom at 120 ⁰C ~ 330 hr-1) and thermodynamically stable. Under dry conditions, the main product above 100 ⁰C is N2 with N2O being the minor product. Water promotes low-temperature activity of 0.1 Rh/CeO2 starting 50 ⁰C with full NO conversion above 125 ⁰C in the wet stream. In this case, however, ammonia and nitrogen are the main products with only minor N2O amounts. NH3 formation at such relatively low temperatures is attractive because of the potential to use this as a passive SCR system. Because of the uniformity of Rh ions on the support, we are able to clarify the mechanistic aspects of this reaction. More specifically, we show that ammonia formation correlates with the WGS activity of the material and thus, rhodium hydride Rh-H species are believed to be involved in this reaction. These findings provide new mechanistic understanding for the catalytically active species in TWC catalysis and open up a new avenue for the synthesis of industrially relevant emissions control catalysts with 100% atom economy of ultra-expensive precious metals such as Rh.
M. Lampón, , , A. Sánchez-López, M. Salz, S. Czesla, J. Sanz-Forcada, K. Molaverdikhani, F. J. Alonso-Floriano, L. Nortmann, et al.
Published: 7 April 2020
Astronomy & Astrophysics, Volume 636; doi:10.1051/0004-6361/201937175

Abstract:
Context. HD 209458 b is an exoplanet with an upper atmosphere undergoing blow-off escape that has mainly been studied using measurements of the Lyα absorption. Recently, high-resolution measurements of absorption in the He I triplet line at 10 830 Å of several exoplanets (including HD 209458 b) have been reported, creating a new opportunity to probe escaping atmospheres. Aims. We aim to better understand the atmospheric regions of HD 209458 b from where the escape originates. Methods. We developed a 1D hydrodynamic model with spherical symmetry for the HD 209458 b thermosphere coupled with a non-local thermodynamic model for the population of the He I triplet state. In addition, we performed high-resolution radiative transfer calculations of synthetic spectra for the helium triplet lines and compared them with the measured absorption spectrum in order to retrieve information about the atmospheric parameters. Results. We find that the measured spectrum constrains the [H]/[H+] transition altitude occurring in the range of 1.2 RP–1.9 RP. Hydrogen is almost fully ionised at altitudes above 2.9 RP. We also find that the X-ray and extreme ultraviolet absorption takes place at effective radii from 1.16 to 1.30 RP, and that the He I triplet peak density occurs at altitudes from 1.04 to 1.60 RP. Additionally, the averaged mean molecular weight is confined to the 0.61–0.73 g mole−1 interval, and the thermospheric H/He ratio should be larger than 90/10, and most likely approximately 98/2. We also provide a one-to-one relationship between mass-loss rate and temperature. Based on the energy-limited escape approach and assuming heating efficiencies of 0.1–0.2, we find a mass-loss rate in the range of (0.42–1.00) ×1011 g s−1 and a corresponding temperature range of 7125–8125 K. Conclusions. The analysis of the measured He I triplet absorption spectrum significantly constrains the thermospheric structure of HD 209458 b and advances our knowledge of its escaping atmosphere.
, Carlos Garcia Vargas, Jinshu Tian, Libor Kovarik, Nicholas R. Jaegers, János Szanyi, Yong Wang
Published: 7 April 2020
Abstract:
We show for the first time that single positively-charged Rh atoms on ceria, prepared via high-temperature atom trapping synthesis, are the highly active species for (CO+NO) reaction both under dry and wet, industrial conditions. This provides a direct link between organometallic homogeneous Rh(I) complexes capable of catalyzing dry (CO+NO) reaction and supported Rh single atoms, the latter being much more active than their homogeneous analogues. Decreasing the Rh loading from to 0.1 wt% leads to a catalyst with uniform Rh ions on the surface of ceria, which is very active (full NO conversion >120 ⁰C, TOF per Rh atom at 120 ⁰C ~ 330 hr-1) and thermodynamically stable. Under dry conditions, the main product above 100 ⁰C is N2 with N2O being the minor product. Water promotes low-temperature activity of 0.1 Rh/CeO2 starting 50 ⁰C with full NO conversion above 125 ⁰C in the wet stream. In this case, however, ammonia and nitrogen are the main products with only minor N2O amounts. NH3 formation at such relatively low temperatures is attractive because of the potential to use this as a passive SCR system. Because of the uniformity of Rh ions on the support, we are able to clarify the mechanistic aspects of this reaction. More specifically, we show that ammonia formation correlates with the WGS activity of the material and thus, rhodium hydride Rh-H species are believed to be involved in this reaction. These findings provide new mechanistic understanding for the catalytically active species in TWC catalysis and open up a new avenue for the synthesis of industrially relevant emissions control catalysts with 100% atom economy of ultra-expensive precious metals such as Rh.
Kent W. Mayhew
European Journal of Applied Physics, Volume 2; doi:10.24018/ejphysics.2020.2.2.5

Abstract:
We shall enhance our understanding of temperature, as was introduced in a previous paper [1]. Temperature is traditionally treated as if it has a linear relation of a system’s thermal energy, throughout most temperature regimes. The limitation of temperature’s relations will be discussed. Also, an improved understanding as to why various system’s measurement of temperature, does represent a measurement of that system’s thermal energy. It will further be discussed why statistical thermodynamics is mistaken with its various assertions, ending with a discussion as to why Maxwell-Boltzmann’s speed distribution is at best, only a rough to good approximation for what is witnessed in experimental gaseous systems.
, Eva Bredow, , Fausto Ferraccioli
Published: 23 March 2020
Abstract:
<p>Numerous unresolved issues exist regarding the lithosphere of Antarctica, especially in terms of its fundamental density, temperature, and compositional structure. Estimates of total lithospheric thickness typically involve assumptions on the depth of the Moho discontinuity, which remains ill-constrained in several parts of Antarctica. Recent estimates of the Moho depth from different geophysical methods show significant discrepancies of 10-20 km in large sectors of the continent. While seismological methods suffer from a limited station coverage and ice reverberation, potential field methods, such as gravity studies, are inherently non-unique. By modelling multiple geophysical parameters in a consistent way and accounting for thermodynamically stable mineral phases of rocks as a function of pressure and temperature conditions, we were able to mitigate the detrimental effects of data sparseness while also reducing geophysical inconsistencies and ambiguities. Gravity gradient data from ESA&#8217;s satellite mission &#8216;GOCE&#8217; are used here to constrain the density distribution within the lithosphere in an integrated 3D model of the Antarctic continent. Independent seismic estimates serve as a benchmark for the robustness of our results. Our model derives new estimates of the crustal and the total lithospheric thickness of Antarctica.<br>Based on our new 3D lithospheric model, we investigate the feasibility of a mantle plume beneath parts of West Antarctica, which has been inferred from previous geochemistry, seismology, and glacial isostatic adjustment studies. The impact of thermal anomalies, simulating ponded plume material, on different geophysical parameters, such as geothermal heat flux, seismic velocities, mineral phase transition changes, gravity, and topographic elevation are modelled for both Marie Byrd Land and Ross Island, two key candidate sites for putative plumes. Combined interpretation of the results is performed together with current understanding of geodynamic processes, such as locations of the LLVPs at the core-mantle boundary, representing potential &#8216;cradles&#8217; for plumes.<br>Our results suggest that a deep-rooted mantle plume is unlikely beneath West Antarctica. However, the observed low seismic velocity zones could still correspond to proposed hot upper mantle zones characterised by lower viscosity. Alternative/additional explanations, such compositional effects and water content as causes for the seismic anomalies must also be further evaluated to better assess their effects on mantle viscosities. This is particularly important beneath regions of recent ice mass loss and recently observed remarkably high rates of GIA-induced bedrock uplift, such as the Amundsen Sea Embayment.</p>
M. Lampón, M. López-Puertas, L. M. Lara, A. Sánchez-López, M. Salz, S. Czesla, J. Sanz-Forcada, K. Molaverdikhani, F. J. Alonso-Floriano, L. Nortmann, et al.
Published: 10 March 2020
by ArXiv
Abstract:
HD 209458b is an exoplanet with an upper atmosphere undergoing blow-off escape that has mainly been studied using measurements of the Ly-alpha absorption. Recently, high-resolution measurements of absorption in the He I triplet line at 10830 angstroms of several exoplanets (including HD 209458b) have been reported, creating a new opportunity to probe escaping atmospheres. We aim to better understand the atmospheric regions of HD 209458b from where the escape originates. We developed a 1D hydrodynamic model with spherical symmetry for the HD 209458 b thermosphere coupled with a non-local thermodynamic model for the population of the He triplet state. In addition, we performed high-resolution radiative transfer calculations of synthetic spectra for the He triplet lines and compared them with the measured absorption spectrum in order to retrieve information about the atmospheric parameters. We find that the measured spectrum constrains the [H]/[H$^{+}$] transition altitude occurring in the range of 1.2 to 1.9Rp. H is almost fully ionised at altitudes above 2.9Rp. We also find that the X-ray and EUV absorption takes place at effective radii from 1.16 to 1.30Rp, and that the He triplet peak density occurs at altitudes from 1.04 to 1.60Rp. Additionally, the averaged mmw is confined to the 0.61-0.73 g/mole interval, and the thermospheric H/He ratio should be larger than 90/10, and most likely approximately 98/2. We also provide a one-to-one relationship between mass-loss rate and temperature. Based on the energy-limited escape approach and assuming heating efficiencies of 0.1-0.2, we find a mass-loss rate in the range of (0.42-1.00)$\times 10^{11}$ g/s and a corresponding temperature range of 7125 to 8125K. The analysis of the measured He triplet absorption spectrum significantly constrains the thermospheric structure of HD 209458b and advances our knowledge of its escaping atmosphere.
, , Gloter Alexandre, Verlaguet Anne, Bellahsen Nicolas
Published: 9 March 2020
Abstract:
<p>Strain localisation in the upper crust is strongly influenced by the presence of phyllosilicates (e.g. white mica, biotite, chlorite), systematically observed in shear zones in granites. Identifying reactions involving phyllosilicates at low-grade metamorphic conditions is crucial to understand crust mechanics and fluid-granite interactions during deformation. In the 305 Ma old basement of the Bielsa massif (Axial Zone, Pyrenees), extensive pre-orogenic (i.e. pre-Alpine) alteration related to feldspar sericitization and chloritization of biotite and amphibole occurred at temperatures of 270&#8211;350&#176;C at 230&#8211;300 Ma. This event was followed by mylonitization and fracturing at 40&#8211;70 Ma, and fluid&#8211;rock interaction at 200&#8211;280&#176;C marked by replacement and new crystallization of chlorite and white mica. In undeformed parts of the granite, compositional maps reveal in situ reaction, high local heterogeneities and low element mobility (migration over few &#181;m) for most elements. Transmission electron microscopy (TEM) shows disconnected reaction-induced nanoporosity in chloritized amphiboles and ripplocations in chloritized biotite. Chloritization reaction varies over tens of nanometres, indicating high variability of element availability. Equilibrium is reached locally due to isolation of fluid in pockets. In samples with fractures, both elemental maps and TEM images show two chlorite groups: alpine chlorites in fractures have homogeneous composition while pre-alpine chlorites in the matrix show patchy compositions. Channelization of fluids in fractures and sealing by chlorite prevented replacement of the matrix chlorite. High element mobility was therefore limited to fractures. In mylonites, compositional maps show secondary chlorites up to 1 mm around cracks and only partial replacement of chlorite within the matrix. This suggests fluids could percolate from cracks to the matrix along chlorite grain boundaries. TEM images show nanocracks at the boundary of chlorite crystallites where replacement is localised. Crystallites were individually replaced by dissolution-reprecipitation reactions and not by intra-crystallite mineral replacement, explaining the patchy compositional variations. While fracturing did not allow chlorite sheets to be progressively re-oriented, a continuous, brittle-ductile deformation in mylonites did, making preferential fluid pathways progressively change.&#160; Despite high strain, chlorite replacement was not complete even in mylonites. Replacement appears to be controlled by matrix-fracture porosity contrasts and the location and connection of nanoporosity between crystallites, criteria that may be only transiently met in space during deformation. These mechanisms need to be taken into account when attempting to reconstruct the metamorphic history of shear zones as well as the evolution of their mechanical behaviour since they affect the scale of the thermodynamic equilibrium and the preservation of hydrothermal metamorphism in granites.</p>
Joscha Henheik,
Reviews in Mathematical Physics, Volume 33; doi:10.1142/s0129055x20600041

The publisher has not yet granted permission to display this abstract.
Kent W. Mayhew
European Journal of Engineering and Technology Research, Volume 5, pp 264-270; doi:10.24018/ejers.2020.5.3.1806

Abstract:
The various relationships between the temperature’s witnessed here on Earth, the Sun’s isolation, thermal energy and blackbody radiation are all poorly understood. Herein, the interrelations are examined, and a new theory concerning their relationships is presented. This also puts limitations upon temperature being related to a system’s thermal energy density. It also gives new insights into why inferences based upon infrared spectrometry, do not match those associated with heat capacities. Furthermore, new understandings concerning the inelastic nature of both intermolecular and intramolecular collisions will be proposed. This all will have profound implications to our understanding of thermodynamics, such as what is blackbody radiation, thermal radiation, and temperature, cumulating in profound implications concerning how we view global warming.
, Mark Smith, Dushyant Shekhawat
Published: 1 March 2020
Fuel, Volume 263; doi:10.1016/j.fuel.2019.116738

Abstract:
Investigation of the redox reactivity of mixed-metal oxides in Chemical-Looping Combustion (CLC) can improve our understanding of the associated reaction mechanisms that are related to this technology. The Fe-Mn-based oxygen carrier supported on a spent fluid catalytic cracking catalyst (FCC) was characterized during CLC of CH4 by fixed bed reactor studies coupled with mass spectrometry, X-ray diffraction, and Raman spectroscopic analysis. Research was carried out to investigate Mn interaction with the FCC support during the high temperature (1100 °C) CLC and the potential impact on performance. The addition of Mn to Fe/FCC led to an increase in the oxygen transfer capacity at 900 °C and a decrease in oxygen transfer capacity at 1100 °C. Following 15 redox cycles, the average methane conversion was 85% at 900 °C and 68% at 1100 °C. The Fe-Mn/FCC carriers were selective for CO2 at 900 °C, and selective for CO at 1100 °C, which is consistent with the thermodynamic limitation of CO2 production at high-temperature. The Fe-Mn/FCC oxygen carrier’s crystal structure remained stable at 900 °C, whereas at 1100 °C, XRD and Raman spectroscopic analysis revealed formation of MnAl2O4 and Al2Mn3Si3O12 phases due to reduced Mn metal alloying with the aluminosilicate. The decrease in reactivity and oxygen transfer capacity at 1100 °C was attributed to the formation of new Fe-Mn phases and alloying with the aluminosilicate, sintering, and agglomeration at high-temperature. These results demonstrate the need to stabilize the Mn-active phase of oxygen carriers on aluminosilicate supports being used for the high-temperature CLC application.
Joscha Henheik, Stefan Teufel
Published: 20 February 2020
by ArXiv
Abstract:
We first review the problem of a rigorous justification of Kubo's formula for transport coefficients in gapped extended Hamiltonian quantum systems at zero temperature. In particular, the theoretical understanding of the quantum Hall effect rests on the validity of Kubo's formula for such systems, a connection that we review briefly as well. We then highlight an approach to linear response theory based on non-equilibrium almost-stationary states (NEASS) and on a corresponding adiabatic theorem for such systems that was recently proposed and worked out by one of us in [51] for interacting fermionic systems on finite lattices. In the second part of our paper we show how to lift the results of [51] to infinite systems by taking a thermodynamic limit.
Published: 17 February 2020
Energies, Volume 13; doi:10.3390/en13040880

Abstract:
Hydrates that form during transport of hydrocarbons containing free water, or water dissolved in hydrocarbons, are generally not in thermodynamic equilibrium and depend on the concentration of all components in all phases. Temperature and pressure are normally the only variables used in hydrate analysis, even though hydrates will dissolve by contact with pure water and water which is under saturated with hydrate formers. Mineral surfaces (for example rust) play dual roles as hydrate inhibitors and hydrate nucleation sites. What appears to be mysterious, and often random, is actually the effects of hydrate non-equilibrium and competing hydrate formation and dissociation phase transitions. There is a need to move forward towards a more complete non-equilibrium way to approach hydrates in industrial settings. Similar challenges are related to natural gas hydrates in sediments. Hydrates dissociates worldwide due to seawater that leaks into hydrate filled sediments. Many of the global resources of methane hydrate reside in a stationary situation of hydrate dissociation from incoming water and formation of new hydrate from incoming hydrate formers from below. Understanding the dynamic situation of a real hydrate reservoir is critical for understanding the distribution characteristics of hydrates in the sediments. This knowledge is also critical for designing efficient hydrate production strategies. In order to facilitate the needed analysis we propose the use of residual thermodynamics for all phases, including all hydrate phases, so as to be able to analyze real stability limits and needed heat supply for hydrate production.
Published: 24 January 2020
by Wiley
The publisher has not yet granted permission to display this abstract.
, Mohammad Amin Alibakhshi, Quan Xie, Jason Riordon, Yi Xu, ,
Accounts of Chemical Research, Volume 53, pp 347-357; doi:10.1021/acs.accounts.9b00411

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Farhan Ahmad, , Hassan Masood, Patrick J. Cullen, , ,
ACS Sustainable Chemistry & Engineering, Volume 8, pp 1888-1898; doi:10.1021/acssuschemeng.9b06180

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Gregory Houchins,
Journal of The Electrochemical Society, Volume 167; doi:10.1149/2.0062007jes

Abstract:
Layered Li(Ni,Mn,Co,)O2 (NMC) presents an intriguing ternary alloy design space for optimization as a cathode material in Li-ion batteries. In the case of NMC, however, only a select few proportions of transition metal cations have been attempted and even fewer have been adopted on a large scale. Recently, the high cost and resource limitations of Co have added a new design constraint and high Ni-containing NMC alloys have gained enormous attention despite possible performance trade-offs. Although the limited collection of NMC cathodes have been successful in providing the performance needed for many applications, specifically electric vehicles, this concern around Co requires further advancement and optimization within the NMC design space. Additionally, it is not fully understood if this material space is a disordered solid solution at room temperature and any arbitrary combination can be used or if there exist distinct transition metal orderings to which meta-stable solid solutions will decay during cycling and affect performance. Here, we present a high fidelity computational search of the ternary phase diagram with an emphasis on high-Ni, and thus low Co, containing compositional phases to understand the room temperature stability of the ordered and disordered solid solution phases. This is done through the use of density functional theory training data fed into a reduced order model Hamiltonian that accounts for effective electronic and spin interactions of neighboring transition metal atoms at various lengths in a background of fixed composition and position lithium and oxygen atoms. This model can then be solved to include finite temperature thermodynamics into a convex hull analysis to understand the regions of ordered and disordered solid solution as well the transition metal orderings within the ordered region of the phase diagram. We also provide a method to propagate the uncertainty at every level of the analysis to the final prediction of thermodynamically favorable compositional phases thus providing a quantitative measure of confidence for each prediction made. Due to the complexity of the three component system, as well as the intrinsic error of density functional theory, we argue that this propagation of uncertainty, particularly the uncertainty due to exchange-correlation functional choice is necessary to have reliable and interpretable results. We find that for the majority of transition metal compositions of the layered material, specifically medium to high-Ni content, prefer transition metal ordering and predict the collection of preferred compositions in the ordered region.
Osmar Pinto Jr., Iara R. C. A. Pinto
American Journal of Climate Change, Volume 09, pp 266-273; doi:10.4236/ajcc.2020.93017

Abstract:
Physical concepts based on the Clausius-Clapeyron relation and on the thermodynamics and aerosol characteristics associated with updrafts, global climate models assuming different parametrizations and lightning-related output variables, and lightning-related data (thunderstorm days) are being used to infer the lightning incidence in a warmer planet, motivated by the global warming observed. In all cases, there are many gaps to be overcome making the lightning response to the global temperature increase still unpredicted. Values from almost 0% (no increase) to 100% have been estimated, being 10% the most common value. While the physical concepts address only part of the problem and the global climate models need to make many simple assumptions, lightning-relate data have strong time and space limitations. In this context, any new evidence should be considered as an important contribution to better understand how will be the lightning incidence in the future. In this article, we described new results about the occurrence of thunderstorms from 1850 to 2010 (a period of 160 years) in the city of Rio de Janeiro, in the Southeast of Brazil. During this period thunderstorm days were recorded in the same location, making this time series one of the longest series of this type available worldwide. The data support an increase of 21% in the mean annual thunderstorm days during the period, while surface temperature increased by 0.6°C during the period. Considering that the mean annual number of thunderstorm in the beginning of this period was 29, we found an increase of one thunderstorm day per 0.1°C of increase in the surface temperature. Assuming that the number of lightning flashes per thunderstorm remains approximately constant during the period, this number corresponds to an increase in the lightning flash rate of approximately 35% per °C of increase of temperature. In addition, considering that the increase of the global temperature during the period was almost the same that observed in Rio de Janeiro, we can conclude that this increase in the lightning flash rate is due to the global warming with no effect of urban activity. Finally, we found that monthly thunderstorm days and monthly mean surface temperature show a linear correlation with a coefficient of 0.9 along the period.
Tiwei Xue, Zengyuan Guo, Tian Zhao
Chinese Science Bulletin, Volume 64, pp 3030-3040; doi:10.1360/tb-2019-0131

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N. Lokesh, Johnny Hioe, Johannes Gramüller,
Journal of the American Chemical Society, Volume 141, pp 16398-16407; doi:10.1021/jacs.9b07841

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Maria Roberta Longhitano, Fabien Sixdenier, , Laurent Krähenbühl, Christophe Geuzaine
COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Volume 38, pp 1595-1613; doi:10.1108/compel-12-2018-0535

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, Tanja Stolzke, Michael Knierbein, Michel W. Jaworek, Trung Quan Luong, , Gabriele Sadowski
Published: 1 September 2019
Biophysical Chemistry, Volume 252; doi:10.1016/j.bpc.2019.106209

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Published: 11 July 2019
Metals, Volume 9; doi:10.3390/met9070777

Abstract:
Recent environmental restrictions constrained car manufacturers to promote cast aluminum alloys working at high temperatures (180 °C–300 °C). The development of new alloys permits the fabrication of higher-strength components in engine downsizing. Those technologies increase internal loadings and specific power and stretch current materials to their limits. Transition metals in aluminum alloys are good candidates to improve physical, mechanical, and thermodynamic properties with the aim of increasing service life of parts. This study is focused on the modified AlSi7Cu3.5Mg0.15 alloy where Mn, Zr, and V have been added as alloying elements for high-temperature applications. The characterization of the cast alloy in this study helps to evaluate and understand its performance according to their physical state: As-cast, as-quenched, or artificially aged. The precipitation kinetics of the AlSi7Cu3.5Mg0.15 (Mn, Zr, V) alloy has been characterized by differential scanning calorimetry (DSC), transmission electron microscopy (TEM) observations, and micro-hardness testing. The Kissinger analysis was applied to extract activation energies from non-isothermal DSC runs conducted at different stationary heating rates. Finally, first-order evaluations of the interfacial mobility of precipitates were obtained.
Sahil Bhandari, Shahzad Gani, Kanan Patel, Dongyu S. Wang, Prashant Soni, Zainab Arub, Gazala Habib, ,
Published: 24 June 2019
Abstract:
Delhi, India, is the second most populated city in the world and routinely experiences some of the highest particulate matter concentrations of any megacity on the planet, posing acute challenges to public health (World Health Organization, 2018). However, the current understanding of the sources and dynamics of PM pollution in Delhi is limited. Measurements at the Delhi Aerosol Supersite (DAS) provide a long-term chemical characterization of ambient submicron aerosol in Delhi, with near-continuous online measurements of aerosol composition. Here we report on source apportionment based on positive matrix factorization (PMF), conducted on 15 months of highly time-resolved speciated submicron non-refractory PM1 (NRPM1) between January 2017 and March 2018. We report on seasonal variability across four seasons of 2017 and interannual variability using data from the two winters and springs of 2017 and 2018. We show that a modified tracer-based organic component analysis provides an opportunity for a real-time source apportionment approach for organics in Delhi. Thermodynamic modeling allows estimation of the importance of ventilation coefficient (VC) and temperature in controlling primary and secondary organic aerosol. We also find that primary aerosol dominates severe air pollution episodes.
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