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Kent W. Mayhew
Published: 25 March 2020
European Journal of Applied Physics, Volume 2; https://doi.org/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.
Johannes Landesfeind, Maximilian Graf, Hubert A. Gasteiger
Published: 1 January 2017
Abstract:
The ion-transport model for concentrated electrolyte solutions introduced by Newman and Thomas-Alyea1is frequently used for numerical simulations of battery systems and depends on three ion transport parameters: the conductivity, the transference number and the binary diffusion coefficient. In addition, the thermodynamic factor, which is derived from the mean molar activity coefficient, is required for the correct description of the thermodynamic behavior of a binary electrolyte solution. The resistive ion transport of the binary electrolyte in a lithium ion battery causes the formation of temperature gradients, especially in large format cells. To understand the influence of local temperature inhomogeneity on, e.g., the aging of the cell, it is necessary to have a profound understanding of the temperature dependence of the ion transport parameters. While a vast spectrum of physico-chemical parameters can be found in the literature only few publications study their temperature dependence, e.g., Valoen and Reimers2. In addition, some of the parameters are often fitted to match experimental performance data and may thus be fitting parameters rather than intrinsic physico-chemical parameters with predictive capability. We present the results of our temperature dependent study of the ionic transport parameters from commonly used lithium electrolytes by using a new method to determine the thermodynamic factor3and combining it with concentration cell experiments to determine transference numbers. Using common polarization cell experiments, we additionally determine diffusion coefficients while conductivities are measured using turn-key equipment. We chose common battery electrolytes, e.g., LiPF6 in EC:EMC (3:7 w:w) and LiPF6 in EC:DMC (1:1 w:w) for our analysis. Exemplarily shown in Figure 1. is the relative temperature dependence of the transference number, thermodynamic factor and the diffusion coefficient for a 0.1 M, 1 M and a 2 M LiClO4in EC:DEC (1:1 w:w) electrolyte. Our results allow us to use numerical experiments to study the temperature dependent transport limitations in binary electrolyte and their influence on the cell performance. Adaption of our transport parameters in Newman type battery models will enhance numerical predictions. The study of temperature variations in large format cells might help to understand the observed, spatially dependent aging in, e.g., cylindrical cells and thereby enables the design and improvement of better lithium ion batteries in the future. Figure 1. Relative change of transference number, binary diffusion coefficient and thermodynamic factor versus their 20°C value a LiClO4in EC:DEC (1:1 w:w) electrolyte at 0.1, 1 and 2 M concentrations. References [1] J. Newman and K. Thomas-Alyea, Electro-chemical Systems, 3rd ed., Wiley Interscience, Hoboken, (2004). [2] L. O. Valøen and J. N. Reimers, J. Electrochem. Soc., 152, A882 (2005). [3] J. Landesfeind, A. Ehrl, M. Graf, W. A. Wall, and H. A. Gasteiger, J. Electrochem. Soc., 163, A1254–A1264 (2016). Acknowledgements We gratefully acknowledge the funding by the Bavarian Ministry of Economic Affairs and Media, Energy, and Technology for its financial support under the auspices of the EEBatt project. Figure 1
D.C. McPhail
Published: 1 March 1995
Geochimica Et Cosmochimica Acta, Volume 59, pp 851-866; https://doi.org/10.1016/00167-0379(40)0353x-

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, , , Frédéric Chevy, Christophe Salomon
Published: 4 November 2009
Abstract:
From sand piles to electrons in metals, one of the greatest challenges in modern physics is to understand the behavior of an ensemble of strongly interacting particles. A class of quantum many-body systems such as neutron matter and cold Fermi gases share the same universal thermodynamic properties when interactions reach the maximum effective value allowed by quantum mechanics, the so-called unitary limit [1,2]. It is then possible to simulate some astrophysical phenomena inside the highly controlled environment of an atomic physics laboratory. Previous work on the thermodynamics of a two-component Fermi gas led to thermodynamic quantities averaged over the trap [3-5], making it difficult to compare with many-body theories developed for uniform gases. Here we develop a general method that provides for the first time the equation of state of a uniform gas, as well as a detailed comparison with existing theories [6,14]. The precision of our equation of state leads to new physical insights on the unitary gas. For the unpolarized gas, we prove that the low-temperature thermodynamics of the strongly interacting normal phase is well described by Fermi liquid theory and we localize the superfluid transition. For a spin-polarized system, our equation of state at zero temperature has a 2% accuracy and it extends the work of [15] on the phase diagram to a new regime of precision. We show in particular that, despite strong correlations, the normal phase behaves as a mixture of two ideal gases: a Fermi gas of bare majority atoms and a non-interacting gas of dressed quasi-particles, the fermionic polarons [10,16-18].
, Consuelo Carli, Giuseppe Cannistraro, Jose Pascoa, Shivesh Sharma
Published: 19 January 2021
International Journal of Heat and Mass Transfer, Volume 170, pp 120983-120983; https://doi.org/10.1016/j.ijheatmasstransfer.2021.120983

Abstract:
We are living an extraordinary season of uncertainty and danger, which is caused by SARS-Cov-2 infection and consequent COVID-19 infection. This preliminary study comes from both a mix of entrepreneurial experience and scientific research. It is aimed by the exigency to reach a new and more effective analysis of the risks on the filed and to reduce them inside a necessary cooperation process which may regard both research and some of the economic activities which are damaged by passive protection measures such as indiscriminate lockdowns. This global emergency requires specific efforts by any discipline that regards specific problems which need to be solved urgently. The characteristic airborne diffusion patterns of COVID-19 shows that the airborne presence of viruses depends on multiple factors which include the dimension of microdroplets emitted by a contagious person, the atmospheric temperature and humidity, the presence of atmospheric particulate and pollution, which may act as a transport vehicle for the virus. The pandemic diffusion shows a particular correlation with the air quality and levels of atmospheric pollution. Specific problems need to solved to understand better the virus, its reliability, diffusion, replication, how it attacks the persons and the conditions, which drives to both positive and deadly evolution of the illness. Most of these problems may benefit from the contribution from both heat and mass transfer and the unsteady thermodynamics of living systems which evolves according to constructal law. After the bibliographic research on the virus, emissive and spread modes, and consequent today adopted protection, a detailed analysis of the contributions which may be assessed by research in thermodynamics, heat and mass transfer, technical and chemical physics. Some possible areas of research have been identified and discussed to start an effective mobilization which may support the effort of the research toward a significant reduction of the impacts of the pandemic infection and the economic risks of new generalized lockdowns.
Kent W. Mayhew
European Journal of Engineering and Technology Research, Volume 5, pp 264-270; https://doi.org/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.
Kent W. Mayhew
European Journal of Engineering and Technology Research, Volume 5, pp 264-270; https://doi.org/10.24018/ejeng.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.
Published: 6 May 2020
by MDPI
Journal: Materials
Materials, Volume 13; https://doi.org/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.
Stefan L. Been, , John H. G. M. Klaessens
Published: 10 February 2011
by SPIE
Abstract:
Visualisation of the thermo dynamics of surgical coagulation devices like laser, diathermy and RFA devices in tissue are essential to get better understanding about the principles of operation of these devices. Thermo cameras have the ability to measure absolute temperatures. However, the visualization of temperature fields using thermal imaging has always been limited to the surface of a medium. We have developed a new strategy to look below the surface of biological tissue by viewing through a ZincSelenide window positioned alongside a block of tissue. When exposed from above with an energy source, the temperature distribution below the surface can be observed through the window. To obtain a close-up view, the thermo camera is enhanced with special macro optics. The thermo dynamics during tissue interaction of various electro surgery modes was studied in biological tissues to obtain a better understanding of the working mechanism. Simultaneously with thermal imaging, normal close-up video footage was obtained to support the interpretation of the thermal imaging. For comparison, temperature gradients were imaged inside a transparent tissue model using color Schlieren imaging. The new subsurface thermal imaging method gives a better understanding of interaction of thermal energy of surgical devices and contributes to the safety and the optimal settings for various medical applications. However, the technique has some limitations that have to be considered. The three imaging modalities showed to be both compatible and complementary showing the pro- and cons- of each modality.
Andreas Kürten
Published: 29 January 2019
Abstract:
Understanding new particle formation and growth is important because of the strong impact of these processes on climate and air quality. Measurements to elucidate the main new particle formation mechanisms are essential; however, these mechanisms have to be implemented in models to estimate their impact on the regional and global scale. Parameterizations are computationally cheap ways of implementing nucleation schemes in models but they have their limitations, as they do not necessarily include all relevant parameters. Process models using sophisticated nucleation schemes can be useful for the generation of look-up tables in large-scale models or for the analysis of individual new particle formation events. In addition, some other important properties can be derived from a process model that implicitly calculates the evolution of the full aerosol size distribution, e.g., the particle growth rates. Within this study, a model (SANTIAGO, Sulfuric acid Ammonia NucleaTIon And GrOwth model) is constructed that simulates new particle formation starting from the monomer of sulfuric acid up to a particle size of several hundred nanometers. The smallest sulfuric acid clusters containing one to four acid molecules and varying amount of base (ammonia) are allowed to evaporate in the model, whereas growth beyond the pentamer (5 sulfuric acid molecules) is assumed to be entirely collision-controlled. The main goal of the present study is to derive appropriate thermodynamic data needed to calculate the cluster evaporation rates as a function of temperature. These data are derived numerically from CLOUD (Cosmics Leaving OUtdoor Droplets) chamber new particle formation rates for neutral sulfuric acid-water-ammonia nucleation at temperatures between 208 K and 292 K. The numeric methods include an optimization scheme to derive the best estimates for the thermodynamic data (dH and dS) and a Monte Carlo method to derive their probability density functions. The derived data are compared to literature values. Using different data sets for dH and dS in SANTIAGO detailed comparison between model results and measured CLOUD new particle formation rates is discussed.
, Douglas E. LaRowe, Alain F. Plante
Published: 10 September 2019
Frontiers in Environmental Science, Volume 7; https://doi.org/10.3389/fenvs.2019.00132

Abstract:
Editorial on the Research TopicEnvironmental Bioenergetics Energy is continuously transformed in the environment through the metabolic activities of organisms. Catabolic reactions generate energy (energy-yielding) which are used to fuel anabolic reactions for maintenance and growth (energy-requiring). These transformations of energy (i.e., bioenergetics) underpin most biogeochemical cycles on Earth and allow the delivery of a wide range of life-supporting ecosystem services. It has long been understood that the amount and types of energy available in an environment influence the rates of biological activity and the complexity of interactions in that system. Traditionally, energy fluxes and stocks have not been described in a quantitative manner, and it is not well-understood how physicochemical theorems such as thermodynamic principles are manifested in environmental systems. Theoretical ecological frameworks (Odum, 1969; Addiscott, 1995) have suggested that the more complex ecosystems become in terms of their food webs, the more efficient they are, i.e., relatively less energy is wasted when utilizing resources. However, this has not been rigorously tested experimentally, but in recent years, scientists in a number of fields have increasingly shown interest in quantifying how bioenergetics constrain and define ecosystem functioning. For example, organic matter in soils has distinct energetic signatures, e.g., energy densities and activation energies (Barré et al., 2016; Williams et al., 2018), and microbial bioenergetics provides empirical data for mechanistic models of carbon turnover in soils, work that is relevant to climate change (Sparling, 1983; Herrmann et al., 2014; Barros et al., 2016; Bölscher et al., 2017). Furthermore, geochemists have quantified the amount of chemolithotrophic energy available for microorganisms in a number of extreme environments to infer the dominant metabolic activities (e.g., McCollom and Shock, 1997; Shock et al., 2010; Osburn et al., 2014). These activities are challenging to monitor due to their inaccessibility and incredibly slow rates of energy processing. Although all of these efforts represent significant progress in the field of biogeochemistry, bioenergetics analysis of natural systems is still in its infancy. Nonetheless, there is increasing interest in using bioenergetics tools to better characterize biogeochemical cycling in water, soils, and sediments in terrestrial, freshwater, and marine ecosystems. In this general context, this Research Topic aims to gather contributions from scientists working in diverse disciplines who have a common interest in evaluating bioenergetics at various spatio-temporal scales in a variety of different environments. The scientific disciplines involved include microbial chemistry, geomicrobiology, extreme microbiology, and soil biogeochemistry, and these articles show the diversity of topics demonstrating the environmental breadth of bioenergetics. In two companion papers, Jin and Kirk and Jin and Kirk explore how pH affects the thermodynamics and kinetics of microbial respiration using geochemical reaction modeling. Their approach is an expansion of the work proposed by Bethke et al. (2011), and by using such a reductionist approach, they show that pH is an important factor in shaping the composition and functioning of microbial communities. In another reductionist approach, Harris et al. examine the capability of nine Shewanella strains to transport extracellular electrons to insoluble electron acceptors such as metal oxides. Five strains are capable of this behavior with some strains showing a preference for a particular metal oxide. Such fundamental studies provide information on underlying basic processes occurring in complex interactions in the environment. Interactions between microorganisms and minerals play an important role in the transformation of rocks in natural systems (Banfield and Nealson, 1997; Shock, 2009). In this Research Topic, Dhami et al. explore the intersection of microbial ecology, geochemistry and the mechanical properties of minerals, and conclude that physicochemical conditions are important in selecting microbial communities under different environmental conditions. Liu et al. address how biologically produced minerals exert influence over the transport of metal ions and thus how microbial behavior modifies ecosystems. Finally, in a modeling article, Vallino and Huber put forward a complementary holistic approach based on thermodynamics. They evaluate the principle of maximum entropy production by combining a metabolic network, a transport model and an entropy production and optimization procedure. In this approach, field observations and modeling are combined and the results support their hypothesis that biological systems evolve and organize to maximize entropy production over a wide range of spatio-temporal scales. Marine (sediment, oceanic basement, seep habitats) and continental (crust, ores, and aquifers) environments are energy-limited habitats. Haas et al. explore the biogeochemistry of anoxygenic photosynthesis in a thick microbial mat in Magical Blue Hole in The Bahamas. When iron is present, sulfur cycling slows down considerably. Yet, despite extreme light limitations, green sulfur bacteria were able to carry out anoxygenic photosynthesis, producing a potential biomarker for extreme low-light environments. In a review paper, Bradley et al. summarize diagenetic models (Arndt et al., 2013) commonly used to evaluate microbial energetics in marine sediments (e.g., growth rate, yield maintenance, and the physiological state of microorganisms), and provide a new model where all factors including dormancy are encompassed. Such a modeling tool will advance our understanding of why microbial communities can persist under unfavorable conditions on geological timescales. Marine sediments therefore can serve as a model system for how life could persist on extra-terrestrial settings. In a review paper, Jones et al. present an overview of how energetic limitation in subsurface environments can serve as potential analogs for life on other planetary bodies. The value of these contributions go beyond our understanding of processes on planet Earth. Soil organic matter serves as carbon and energy source for microorganisms, and the use of the average nominal oxidation state of carbon has been suggested as a universal metric of the bioenergetics potential of microbial metabolism decomposing organic matter in soils (LaRowe and Van Cappellen, 2011; Nunan et al., 2015; Gunina et al., 2017). In the current Research Topic, Boye et al. extend this approach to make progress on sustainable land-use management issues such as the degradation of organic matter in oxygen-limited rice paddy systems. Using energy balances of redox-processes, their results indicate that water-soluble carbon is key driver of microbial processes with major impacts on ecosystem functioning. Arcand et al. explore the functional importance of soil biota, including their composition, in organic and conventional management systems. Combining isothermal calorimetry with 13C-DNA stable isotope probing, they demonstrate that long-term agricultural management can alter microbially driven carbon processes in soils. Furthermore, Williams and Plante propose a bioenergetics framework for assessing the persistence of organic matter in soil systems. The framework is based on a return-on-investment ratio, the ratio between energy invested in relation to energy density (Harvey et al., 2016). Their framework contradicts traditional humus theory that organic matter is composed of inherently stable macromolecules; instead it supports the idea that organic matter is a continuum of progressively decomposing organic compounds (Lehmann and Kleber, 2015). The 12 articles comprising this Research Topic only begin to scratch the surface of the very broad emerging research area of environmental bioenergetics. By taking an energetic view of microbial metabolism in various environments, we may (i) further our understanding of the link between microbial communities and their activities in relation to geochemical processes, and (ii) improve our prediction of microbial feedback mechanisms and ecosystem responses to climate change. The publication of this volume comes at a key moment in which the delivery of ecosystem services is of high importance (IPBES, 2019) and the need to achieve the UN Sustainable Development Goals for 2030 (UN-DSDG, 2019) becomes an increasingly urgent issue. We aspire that this collective work will inform and stimulate more studies on this Research Topic in the coming years, and we advocate that environmental bioenergetics research (including development of new concepts and frameworks) needs to be integrated with targeted scientific research to address the pressing challenges humankind is currently faced with. All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The editors want to express their profound gratitude to all authors and reviewers for their valuable contributions, which helped to achieve high standards for the contributed papers. Addiscott, T. M. (1995). Entropy and sustainability. Eur. J. Soil Sci. 46, 161–168. doi: 10.1111/j.1365-2389.1995.tb01823.x CrossRef Full Text | Google Scholar Arndt, S., Jørgensen, B. B., LaRowe, D. E., Middelburg, J., Pancost, R., and Regnier, P. (2013). Quantifying the degradation of organic matter in marine sediments: a review and synthesis. Earth Sci. Rev. 123, 53–86. doi: 10.1016/j.earscirev.2013.02.008 CrossRef Full Text | Google Scholar Banfield, J. F., and Nealson, K. H. (1997). Geomicrobiology: Interactions Between Microbes and Minerals. Washington, DC: Mineralogical Society of America. doi: 10.1515/9781501509247 CrossRef Full Text | Google Scholar Barré, P., Plante, A. F., Cecillon, L., Lutfalla, S., Baudin, F., Bernard, S., et al. (2016). The energetic and chemical signatures of persistent soil organic matter. Biogeochemistry 130, 1–12. doi: 10.1007/s10533-016-0246-0 CrossRef Full Text | Google Scholar Barros, N., Hansen, L. D., Piñeiro, V., Pérez-Cruzado, C., Villanueva, M., Proupín, J., et al. (2016). Factors influencing the calorespirometric ratios of soil microbial metabolism. Soil Biol. Biochem. 92, 221–229. doi: 10.1016/j.soilbio.2015.10.007 CrossRef Full Text | Google Scholar Bethke, C. M., Sanford, R. A., Kirk, M. F., Jin, Q., and Flynn, T. M. (2011). The thermodynamic ladder in geomicrobiology. Am. J. 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Geochemical constraints on chemolithoautotrophic metabolism by microorganisms in seafloor hydrothermal systems. Geochim. Cosmochim. Acta 61, 4375–4391. doi: 10.1016/S0016-7037(97)00241-X PubMed Abstract | CrossRef Full Text | Google Scholar Nunan, N., Lerch, T. Z., Pouteau, V., Mora, P., Changey, F., Kätterer, T., et al. (2015). Metabolising old soil carbon: Simply a matter of simple organic matter? Soil Biol. Biochem. 88, 128–136. doi: 10.1016/j.soilbio.2015.05.018 CrossRef Full Text | Google Scholar Odum, E. P. (1969). The strategy of ecosystem development. Science 164, 262–270. doi: 10.1126/science.164.3877.262 PubMed Abstract | CrossRef Full Text | Google Scholar Osburn, M. R., LaRowe, D. E., Momper, L., and Amend, J. P. (2014). Chemolithotrophy in the continental deep subsurface: Sanford Underground Research Facility (SURF), USA. Front. Microbiol. 5:610. doi: 10.3389/fmicb.2014.00610 PubMed Abstract | CrossRef Full Text | Google Scholar Shock, E. L. (2009). 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Geoderma 330, 107–116. doi: 10.1016/j.geoderma.2018.05.024 CrossRef Full Text | Google Scholar Keywords: energy, thermodynamics, calorimetry, energy-limited environments, soil, sediment Citation: Herrmann AM, LaRowe DE and Plante AF (2019) Editorial: Environmental Bioenergetics. Front. Environ. Sci. 7:132. doi: 10.3389/fenvs.2019.00132 Received: 25 July 2019; Accepted: 27 August 2019; Published: 10 September 2019. Edited and reviewed by: Bradley M. Tebo, Oregon Health & Science University, United States Copyright © 2019 Herrmann, LaRowe and Plante. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Anke M. Herrmann, [email protected]
T. Jungwirth, , J. Mašek, ,
Published: 11 August 2006
Reviews of Modern Physics, Volume 78, pp 809-864; https://doi.org/10.1103/revmodphys.78.809

Abstract:
The body of research on (III,Mn)V diluted magnetic semiconductors (DMSs) initiated during the 1990s has concentrated on three major fronts: (i) the microscopic origins and fundamental physics of the ferromagnetism that occurs in these systems, (ii) the materials science of growth and defects, and (iii) the development of spintronic devices with new functionalities. This article reviews the current status of the field, concentrating on the first two, more mature research directions. From the fundamental point of view, (Ga,Mn)As and several other (III,Mn)V DMSs are now regarded as textbook examples of a rare class of robust ferromagnets with dilute magnetic moments coupled by delocalized charge carriers. Both local moments and itinerant holes are provided by Mn, which makes the systems particularly favorable for realizing this unusual ordered state. Advances in growth and postgrowth-treatment techniques have played a central role in the field, often pushing the limits of dilute Mn-moment densities and the uniformity and purity of materials far beyond those allowed by equilibrium thermodynamics. In (III,Mn)V compounds, material quality and magnetic properties are intimately connected. This review focuses on the theoretical understanding of the origins of ferromagnetism and basic structural, magnetic, magnetotransport, and magneto-optical characteristics of simple (III,Mn)V epilayers, with the main emphasis on (Ga,Mn)As. Conclusions are arrived at based on an extensive literature covering results of complementary ab initio and effective Hamiltonian computational techniques, and on comparisons between theory and experiment. The applicability of ferromagnetic semiconductors in microelectronic technologies requires increasing Curie temperatures from the current record of 173K in (Ga,Mn)As epilayers to above room temperature. The issue of whether or not this is a realistic expectation for (III,Mn)V DMSs is a central question in the field and motivates many of the analyses presented in this review.
Duane O. Muhleman, Arie W. Grossman, Bryan J. Butler, Martin A. Slade
Science, Volume 248, pp 975-980; https://doi.org/10.1126/science.248.4958.975

Abstract:
The present understanding of the atmosphere and surface conditions on Saturn's largest moon, Titan, including the stability of methane, and an application of thermodynamics leads to a strong prediction of liquid hydrocarbons in an ethane-methane mixture on the surface. Such a surface would have nearly unique microwave reflection properties due to the low dielectric constant. Attempts were made to obtain reflections at a wavelength of 3.5 centimeters by means of a 70-meter antenna in California as the transmitter and the Very Large Array in New Mexico as the receiving instrument. Statistically significant echoes were obtained that show Titan is not covered with a deep, global ocean of ethane, as previously thought. The experiment yielded radar cross sections normalized by the Titan disk of 0.38 ± 0.15, 0.78 ± 0.15, and 0.25 ± 0.15 on three consecutive nights during which the sub-Earth longitude on Titan moved 50 degrees. The result for the combined data for the entire experiment is 0.35 ± 0.08. The cross sections are very high, most consistent with those of the Galilean satellites; no evidence of the putative liquid ethane was seen in the reflection data. A global ocean as shallow as about 200 meters would have exhibited reflectivities smaller by an order of magnitude, and below the detection limit of the experiment. The measured emissivity at similar wavelengths of about 0.9 is somewhat inconsistent with the high reflectivity.
Wei Shi, Haiping Lu, Nan Zhang, Chunfang Fan, Amy T. Kan,
Published: 30 May 2012
Abstract:
The ultra-high temperature (150–250°C), pressure (1,000–2,000 bar, 15,000 to 30,000 psi) and TDS (>300,000 mg/L) in deepwater oil and gas production pose significant challenges to scaling control due to limited knowledge of mineral solubility, kinetics and inhibitor efficiency at these extreme conditions. Prediction of thermodynamic properties of common minerals is currently limited by lack of experimental data and inadequate understanding of modeling parameters. In this study, a new apparatus was built to test scale formation and inhibition at high temperatures and pressures. Solubilities of two common minerals, barite and calcite, were tested at temperature up to 250°C, pressure up to 1,500 bar (22,000 psi) and ionic strength up to 6m in solutions with elevated concentrations of mixed electrolytes (e.g., calcium, magnesium, sulfate and carbonate) representing the maximum range of interferences expected (95%CI) in oil and gas wells. As an attempt towards experimentally determining mineral solubility at high temperature, pressure and salinity, not only does this study contribute to the extremely limited data base, but it also provides a reliable approach for evaluating and adjusting model predictions at extreme conditions. Predictions by a thermodynamic model based on Pitzer's ion interaction theory were evaluated using experimental data. The dependence of Pitzer's coefficients for ion activity coefficients on temperature and pressure was examined and incorporated into the scale prediction model, whose prediction is consistent with both experimental and literature data at all conditions tested.
, Kiran R. Patil, Vinod K. Ahirrao, Prasad K. Deshpande, Ravindra D. Yeole, Mahesh V. Patel
Published: 2 January 2019
Analytical Chemistry Letters, Volume 9, pp 20-31; https://doi.org/10.1080/22297928.2019.1588161

Abstract:
WCK 2996 is a new molecular entity comprising of two stereoisomers. It possesses potent antibacterial activity active against gram-positive bacteria. This article describes liquid chromatographic method for the separation of stereoisomers of WCK 2996. The separation was achieved on Chiralpak AD-H (amylose based chiral stationary phase) using a mobile phase consisting of hexane: 2-propanol: methanol: acetic acid (70:10:20:0.2, v/v/v/v) at a flow rate 1.0 mL min-1. Chromatographic resolution (Rs) between two isomers was found to be more than 4. The developed method was extensively validated and proved to be robust. The detector response for stereoisomer-1 (SI-1) and stereoisomer-2 (SI-2) showed an excellent linear correlation over the concentration range 0.05 - 1.0 mg mL-1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.15 and 0.45 μg mL-1 for SI-1 and 0.18 and 0.56 μg mL-1 for SI-2. Average recovery was in the range of 98.0 % to 101.0 % for SI-1 and 99.1 % to 102.0 % for SI-2. Analytical sample solutions were found to be stable up to 48 hrs. The method was found to be specific, sensitive, precise and accurate for quantitative determination of either of isomers. The method was scaled up for preparative separation and successfully applied to isolate the individual pure stereoisomers. One of the isolated stereoisomers was found to be 2 to 4 times more active than the other against various strains of bacteria. The thermodynamic parameters were studied to understand the effect of temperature on separation of stereoisomers. In addition, the effect of organic peak modifier on selectivity of stereoisomers was also studied.
Published: 15 October 2020
by MDPI
Journal: Energies
Energies, Volume 13; https://doi.org/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.
David E Morris, Carol J Burns, Wayne H Smith, Blanchard
Abstract:
Plutonium and uranium residues (e.g., incinerator ash, combustibles, and sand/slag/crucibles) resulting from the purification and processing of nuclear materials constitute an enormous volume of ''lean'' processing waste and represent a significant fraction of the U. S. Department of Energy's (DOE) legacy waste from fifty years of nuclear weapons production activities. Much of this material is presently in storage at sites throughout the DOE weapons production complex (most notably Rocky Flats, Savannah River and Hanford) awaiting further processing and/or final disposition. The chemical and physical stability of much of this material has been called into question recently by the Defense Nuclear Facility Safety Board (DNFSB) and resulted in the issuance of a mandate by the DNFSB to undertake a program to stabilize these materials [1]. The ultimate disposition for much of these materials is anticipated to be geologic repositories such as the proposed Waste Isolation Pilot Plant in New Mexico. However, in light of the mandate to stabilize existing residues and the probable concomitant increase in the volume of material to be disposed as a result of stabilization (e.g., from repackaging at lower residue densities), the projected storage volume for these wastes within anticipated geologic repositories will likely be exceeded simplymore » to handle existing wastes. Additional processing of some of these residue waste streams to reduce radionuclide activity levels, matrix volume, or both is a potentially important strategy to achieve both stabilization and volume reduction so that the anticipated geologic repositories will provide adequate storage volume. In general, the plutonium and uranium that remains in solid residue materials exists in a very stable chemical form (e.g., as binary oxides), and the options available to remove the actinides are limited. However, there have been some demonstrated successes in this vain using aqueous phase electrochemical methods such as the Catalyzed Electrochemical Plutonium Oxide Dissolution (CEPOD) process pioneered by workers at Pacific Northwest National Laboratory in the mid-1970s [2]. The basis for most of these mediated electrochemical oxidation/reduction (MEO/R) processes is the generation of a dissolved electrochemical catalyst, such as Ag2+, which is capable of oxidizing or reducing solid-phase actinide species or actinide sorbates via 7 heterogeneous electron transfer to oxidation states that have significantly greater solubilities (e.g., PuO2(s) to PuO2 2+ (dissolved)). The solubilized actinide can then be recovered by ion exchange or other mechanisms. These aqueous electrochemical methods for residue treatment have been considered in many of the ''trade studies'' to evaluate options for stabilization of the various categories of residue materials. While some concerns generally arise (e.g., large secondary waste volumes could results since the process stream normally goes th rough anion exchange or precipitation steps to remove the actinide), the real utility and versatility of these methods should not be overlooked. They are low temperature, ambient pressure processes that operate in a non-corrosive environment. In principle, they can be designed to be highly selective for the actinides (i.e., no substrate degradation occurs), they can be utilized for many categories of residue materials with little or no modification in hardware or operating conditions, and they can conceivably be engineered to minimize secondary waste stream volume. However, some fundamental questions remain concerning the mechanisms through which these processes act, and how the processes might be optimized to maximize efficiency while minimizing secondary waste. In addition, given the success achieved to date on the limited set of residues, further research is merited to extend the range of applicability of these electrochemical methods to other residue and waste streams. The principal goal of the work described here is to develop a fundamental understanding of the heterogeneous electron transfer thermodynamics and kinetics that lie at the heart of the MEO/R processes for actinide solids and actinide species entrained in or surface-bound to residue substrates. This has been accomplished as described in detail below through spectroscopic characterization of actinide-bearing substrates and electrochemical investigations of electron transfer reactions between uranium- and plutonium- (or surrogates) bearing solids (dispersed actinide solid phases and actinides sorbed to inorganic and organic colloids) and polarizable electrode materials. In general, the actinide solids or substrate-supported species were chosen to represent relevant residue materials (e.g., incinerator ash, sand/slag/crucible, and combustibles).« less
Chandralekha Singh, Kenneth S. Schweizer,
Published: 1 February 1995
The Journal of Chemical Physics, Volume 102, pp 2187-2208; https://doi.org/10.1063/1.468741

Abstract:
Polymer reference interaction site model theory with the new molecular closures is employed to numerically and analytically study structurally and interaction potential symmetric binary blends. Both the compressibility and free energy routes to the thermodynamics are studied and the issue of thermodynamic consistency is addressed. A variety of non‐Flory–Huggins effects, or ‘‘fluctuation phenomena,’’ are found. These include nonuniversal renormalization of the critical temperature and effective chi‐parameter from their mean field values, composition‐dependent chi‐parameters, and nonlinear dependence of the inverse osmotic compressibility on inverse temperature. All these fluctuation effects depend on degree of polymerization, N, chain length asymmetry, polymer density, range and precise form of the attractive tail potentials, chain stiffness, and proximity to the phase boundary. Some of the fluctuation effects are intrinsic, i.e., survive in the long chain N→∞ limit, while others are finite size effects which arise from chain‐connectivity‐induced coupled local density and long wavelength concentration fluctuations. Due to the multiple sources of the fluctuation effects, even asymptotic finite size effects can appear ‘‘intrinsic’’ over extended ranges of N. Comparison with lattice Monte Carlo simulations of Deutsch and Binder shows good agreement with the theoretical predictions. All the fluctuation effects can be understood in simple terms by examining the enthalpy of mixing and local interchain correlations. The key physical process is thermally driven local interchain rearrangements corresponding to the formation of diffuse interfaces and clusters or droplets. Analytic results are derived using the Gaussian thread model, which provides a simple physical understanding of the origin of the numerically determined fluctuation effects. In the long chain limit the predictions for the thread blend are shown to be exactly thermodynamically consistent which is a unique circumstance for liquid state theories. The relation of the blend fluctuation stabilization process to the corresponding diblock copolymer problem is briefly discussed.
Ryan Trottier, Samantha Miller-Millican, Christopher Bartel, Aaron M. Holder, Alan Weimer, Charles Bruce Musgrave
Published: 1 January 2017
Abstract:
To continue to meet global energy demands, efficient methods of utilizing renewable energy must be developed. Converting solar energy into chemical fuels is a promising approach, but efficient and cost effective methods for producing solar fuels have not yet been developed. Solar thermal water splitting is a particularly promising possibility because it has a high theoretical hydrogen production efficiency. However, achieving this efficiency requires finding the proper redox material. Currently, the most promising materials are metal oxides, including spinels and perovskites. These materials split water via a high temperature cycle in which the material is reduced, forming oxygen vacancies, in one step, then oxidized by stripping oxygen from water in the next. An efficient STWS process is extremely demanding on materials and requires that they be thermodynamically capable of being reduced, withstand the high temperatures of solar thermal water splitting, and form oxygen vacancies with enough energy to reduce water. Furthermore, materials must also be kinetically viable, able to complete the water splitting cycle quickly enough to allow for large scale production of hydrogen. The initial reduction step uses concentrated solar energy to heat the material to temperatures exceeding 1350oC and creating oxygen vacancies in the process. This reduced material can subsequently be oxidized by splitting water and forming hydrogen. A variety of materials have been found that can undergo this process, CeO2, FeAl2O4, and SLMA, but they all fall short in some aspect. To discover new STWS materials and optimize these compounds for their STWS abilities, it is important to have a detailed understanding of the electronic structure which governs both the thermodynamics and kinetics of these materials. Using atomistic modeling, we identify the intrinsic material properties that enable high performance for the oxidation and reduction steps of the two-step cycle. This understanding can be used to guide the rational doping of these compounds as well as establish design principles for the design of new high performance materials. While the thermodynamic and kinetics of STWS chemistry can be directly modeled using quantum chemical methods, these calculations are too computationally intensive to examine large numbers of materials to identify promising candidates. This is especially the case for calculations that consider the disordered spin structure and high temperature atomic structure of these materials – which we explicitly account for in our approach. We have developed efficient computational methods to identify STWS materials with desirable thermodynamic and kinetic properties with these critical considerations. We have used high level calculations on a subset of materials to inform a machine learning approach that identifies descriptors for the activation barriers for the rate limiting step for water splitting. These descriptors can be determined from simpler calculations and will allow for rapid calculation and determination of water splitting materials. This work focuses on the use of density functional theory to develop general descriptors of the water splitting reaction and in turn a more fundamental understanding of the reaction mechanism and efficient approach to screening materials for their STWS kinetics.
Published: 5 April 2017
Abstract:
Glass formation has been central to fabrication technologies since the dawn of civilization. Glasses not only encompass window panes, the insulation in our homes, the optical fibers supplying our cable TV, and vessels for eating and drinking, but they also include a vast array of ‘‘plastic’’ polymeric materials. Glasses find applications in high technology (e.g., producing microelectronic materials, etc., amorphous semiconductors), and recent advances have created ‘‘plastic metallic glasses’’ that are promising for fabricating everyday structural materials. Many commercially relevant systems, such as microemulsions and colloidal suspensions, have complex molecular structures and thus solidify by glass formation. Despite the importance of understanding the fundamental nature of glass formation for the synthesis of new materials, a predictive molecular theory has been lacking. Much of our understanding of glass formation derives from the analysis of experimental data, a process that has uncovered a number of interesting universal behaviors, namely, relations between properties that are independent of molecular details. However, these empirically derived relations and their limitations remain to be understood on the basis of theories, and, more importantly, there is strong need for theories of the explicit variation with molecular system to enable the rational design and tailoring of new materials. Wemore » have recently developed the generalized entropy theory, the only analytic, theory that enables describing the dependence of the properties of glass-formation on monomer molecular structures. These properties include the two central quantities of glass formation, the glass transition temperature and the glass fragility parameter, material dependent properties that govern how a material may be processed (e.g., by extrusion, ink jet, molding, etc.) Our recent works, which are further described below, extend the studies of glass formation in polymer systems to test the theory by directly comparing between the predictions of our generalized entropy theory with experiment and with simulations and to expand the vistas of the theory to describe a wider range of important systems (e.g. glass formation in binary blends and systems with specific interactions) and phenomena that are describable by the generalized entropy theory. In addition, we have addressed longstanding fundamental problems associated with the validity of the Adam-Gibbs theory, one of the underpinnings of the general entropy theory. Theoretical advances to enable describing the properties of glass-formation over a wider class of important polymeric systems, included semi-flexible systems, the more general situation of specific interactions, and more. Our recent work removes the simplest approximation uses the simplest model in which the interaction is approximated by a single, monomer average. Thus, the theory has been extended to allow some variations of the energy parameters between the atoms within the monomers. The theory has also been extended to include all the contributions from chain semi-flexibility. Both projects are extremely difficult, but the payback is that the process of solving the problems developed strong theoretical skills in Dr. Xu, who has recently begun a postdoc position at ORNL. The theory has also been extended to describe glass formation in partially miscible blends, with good general agreement with experiment. Again, the development of the theory presented an extremely difficult problem, but the payback is the development of a theory for a very important class of systems. Another project provides an extremely simple approximation for certain properties of glass formation in polymer melts and should make the theory more accessible to everyone.« less
, Petra Panak, Kathy Dardenne, Jörg Rothe, Xavier Gaona, Marcus Altmaier, Horst Geckeis
Published: 10 November 2021
Safety of Nuclear Waste Disposal, Volume 1, pp 159-160; https://doi.org/10.5194/sand-1-159-2021

Abstract:
The Safety Case for a radioactive waste repository in deep geological formations requires detailed chemical and thermodynamic information on the stored radionuclides in their relevant oxidation states. Although a comprehensive summary of critically evaluated thermodynamic data is available via the blue book series of the NEA-TDB (“Nuclear Energy Agency – Thermochemical Database”), the majority of this data is limited to ambient conditions (Grenthe et al., 2020). In the case of the disposal of high-active, heat-producing waste, however, the near-field of the repository will experience increased temperatures at early operative phases for several hundred or a few thousand years. Radionuclides may come into contact with aquatic solutions or brines at elevated temperatures in the case of early canister failure. Besides other factors of the overall disposal concept (e.g. the geometry of the repository, type and amount of stored radionuclide inventories), host rock characteristics themselves limit the extent of the allowable temperature increase. For example, in clay formations the maximum temperature should stay at around or below ∼100∘C in order to avoid an irreversible change in the host rock retention capacity, whereas rock salt allows much higher temperatures of up to 200 ∘C. Increased temperatures will have a distinct impact on the geochemical behaviour of radionuclides, potentially affecting their mobility and retention in the near field. Besides reactions at the solid–liquid interface (e.g. dissolution/precipitation reactions of the waste matrix, sorption reactions of the radionuclides to surfaces), complexation reactions with inorganic and organic ligands present in the aqueous phase potentially affect migration behaviour of the radionuclides. A quantitative thermodynamic description of these processes requires standard stability constants (log⁡βn0(T)), as well as standard reaction enthalpies and entropies (ΔrHm,n0, ΔrSm,n0). The precise experimental determination of these data for all relevant radionuclide/ligand reactions requires a vast amount of time and effort. In this regard, reliable extrapolation methods in particular for standard stability constants valid for 25 ∘C to higher temperatures are considered to support a comprehensive description. Recently, the German Federal Ministry of Education and Research (BMBF)-funded collaborative research project “Therm AC” focused on the experimental determination of new thermodynamic data at higher temperatures, as well as the comparison with the analogous results yielded by extrapolation methods. The Thermochemical Database Project of the OECD-NEA (NEA-TDB) is currently in the process of preparing a comprehensive state-of-the-art report on the high temperature thermodynamics of radionuclides, further emphasizing the particular relevance of this interesting topic. Within this contribution, a critical overview on the recent advances in the field of high temperature studies of radionuclides in aqueous solutions will be given. Besides summarizing information on key technical aspects relevant for high temperature studies, the effect of increased temperatures on the complexation of trivalent actinides with chloride will be discussed in more detail in order to illustrate newly derived in-depth understanding of the impact of increased temperatures on the (geo)chemical behaviour of trivalent actinides on the molecular scale (Skerencak-Frech et al., 2014).
D.D. Whitehurst, H. Farag, T. Nagamatsu, K. Sakanishi, I. Mochida
Published: 19 October 1998
Journal: Catalysis Today
Catalysis Today, Volume 45, pp 299-305; https://doi.org/10.1016/s0920-5861(98)00234-x

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, Pierre Perrot
Published: 1 January 2009
Journal of Nano Research, Volume 4, pp 135-144; https://doi.org/10.4028/www.scientific.net/jnanor.4.135

Abstract:
Our present analysis will focus on the S(V)LS mechanism. In the S(V)LS process, silicon nanowires are grown by heating the metal-coated silicon substrate at high temperature in an argon and hydrogen atmosphere. Here, we demonstrate the origin of the driving force needed for the metal supersaturation and calculate the binary phase diagrams of Au-Si nanosystems involved in the growth of nanowires. These new diagrams can be used for other purposes helping to improve the understanding of the physical properties of nanostructures. We also answer the challenging question that many researchers have addressed on whether a minimum size limit of silicon nanowires exists. The nanowire size limit has been evaluated on the basis of thermodynamics and using silicon nanowires obtained via the S(V)LS rather than the VLS mechanism. At 1100°C, the temperature commonly used for the growth of nanowires by the S(V)LS mechanism, it has been found that there is no minimum size limit of nanowires.
, , Chung Kiak Poh, Abbas Ranjbar, Yanhui Guo, ,
Published: 25 June 2010
Journal of Alloys and Compounds, Volume 500, pp 200-205; https://doi.org/10.1016/j.jallcom.2010.03.242

The publisher has not yet granted permission to display this abstract.
Journal of Thermal Analysis and Calorimetry, Volume 85, pp 179-187; https://doi.org/10.1007/s10973-005-7347-7

The publisher has not yet granted permission to display this abstract.
W. John Dartnall, John A. Reizes
Published: 9 November 2012
Abstract:
Engineering Thermodynamics is that engineering science in which students learn to analyze dynamic systems involving energy transformations, particularly where some of the energy is in the form of heat. It is well known that people have difficulty in understanding many of the concepts of thermodynamics; in particular, entropy and its consequences. However, even more widely known concepts such as energy and temperature are not simply defined or explained. Why is this lack of understanding and clarity of definition prevalent in this subject? Older engineering thermodynamics textbooks (often containing the words “heat engines” in the title) had a strong emphasis in their early chapters on the general physical details of thermodynamic equipment such as internal and external combustion engines, gas compressors and refrigeration systems. The working fluid in these systems might expand or contract while heat, work and mass might cross the system boundary. The molecular workings within the thermodynamic fluid are not of prime concern to the engineer even though they are to a physicist or chemist. Modern engineering thermodynamics textbooks place great emphasis on mathematical systems designed to analyze the behavior and performance of thermodynamic devices and systems, yet they rarely show, at least early in their presentation, graphical images of the equipment; moreover, they tend to give only passing reference to the molecular behavior of the thermodynamic fluid. This paper presents some teaching strategies for placing a greater emphasis on the physical realities of the equipment in conjunction with the molecular structure of the working fluid in order to facilitate a deeper understanding of thermodynamic performance limitations of equipment.
Brad Bessinger, John A. Apps
Abstract:
A comprehensive thermodynamic database based on the Helgeson-Kirkham-Flowers (HKF) equation of state was developed for metal complexes in hydrothermal systems. Because this equation of state has been shown to accurately predict standard partial molal thermodynamic properties of aqueous species at elevated temperatures and pressures, this study provides the necessary foundation for future exploration into transport and depositional processes in polymetallic ore deposits. The HKF equation of state parameters for gold, arsenic, antimony, mercury, and silver sulfide and hydroxide complexes were derived from experimental equilibrium constants using nonlinear regression calculations. In order to ensure that the resulting parameters were internally consistent, those experiments utilizing incompatible thermodynamic data were re-speciated prior to regression. Because new experimental studies were used to revise the HKF parameters for H2S0 and HS-1, those metal complexes for which HKF parameters had been previously derived were also updated. It was found that predicted thermodynamic properties of metal complexes are consistent with linear correlations between standard partial molal thermodynamic properties. This result allowed assessment of several complexes for which experimental data necessary to perform regression calculations was limited. Oxygen fugacity-temperature diagrams were calculated to illustrate how thermodynamic data improves our understanding of depositional processes. Predicted thermodynamic properties were usedmore » to investigate metal transport in Carlin-type gold deposits. Assuming a linear relationship between temperature and pressure, metals are predicted to predominantly be transported as sulfide complexes at a total aqueous sulfur concentration of 0.05 m. Also, the presence of arsenic and antimony mineral phases in the deposits are shown to restrict mineralization within a limited range of chemical conditions. Finally, at a lesser aqueous sulfur concentration of 0.01 m, host rock sulfidation can explain the origin of arsenic and antimony minerals within the paragenetic sequence.« less
Published: 1 December 2016
Aseg Extended Abstracts, Volume 2016, pp 1-3; https://doi.org/10.1071/aseg2016ab189

Abstract:
The past ten years have been marked by dramatic advances in four seemingly isolated research fields: Thermodynamic modelling of minerals and rocks at high PT conditions, numerical simulation of the thermomechanical behaviour of the Earth’s interior, efficient decomposition techniques to solve complex simulation-based problems, and probabilistic data analysis and inversion methods. All these disciplines/techniques have individually created true “revolutions” in the way we understand and model natural systems, including the interior of the Earth. Nevertheless, a more profound understanding is still ahead of us from the formal combination of these disciplines/techniques into a single operational framework to study the physical state of the Earth’s interior. In this contribution, I will present and discuss the concept of multi-observable probabilistic tomography or “thermochemical tomography”. This new kind of tomography is particularly designed for studies of the fundamental thermodynamic variables of the Earth’s lithosphere, namely temperature, pressure and chemical composition. Once these variables are known, all physical parameters of interest (e.g. seismic velocities, density, viscosity, conductivity, etc), as well as traditional tomography images, are also retrieved in a thermodynamically-consistent way. The method is built on a simulation-based inversion technique where multiple satellite (e.g. gravity gradients, geoid height, etc) and land-based (e.g. seismic, plate motions, heat flow, etc) datasets can be jointly inverted to maximize the physical consistency of the resulting Earth model. Assembling this large problem required a collaborative effort between thermodynamicists, mineral physicists, geophysicists and geochemists, and marks the first step towards a full coupling between geophysics, geodynamics, thermodynamics, and geochemistry. I will present results for both synthetic and real case studies, which serve to highlight the advantages and limitations of this approach.
R. Venkatesan, J.L. Creek
Published: 30 April 2007
Abstract:
Arterial wax deposition has been problematic for the industry for many years. The development of new technology progresses in fits and starts. This deposition is differentiated from deposition in the geological sense. The particular characteristics governing the magnitude and occurrence of deposition are:the temperature and pressure must be such that wax precipitates in the flowing phase andthere must be heat flow from the mobile phase to the pipe wall. We also know the deposits formed are not 100% paraffin wax. Yet, some of the relatively new methods proposed for modeling deposition defy some of these well established principles. Experimental challenges also exist. In general, the heat flux in flowing pipelines is far less than that in laboratory experiments. We also know the flow line is not isothermal yet only typically test at one set of temperatures. More serious work needs to be done to develop an understanding of deposition in turbulent flow conditions, deposition over longer time periods, deposition at low heat transfer, and devising methods to obtain credible field data for comparison and guiding research in this area. This presentation will review the current state of the art and propose ways forward. Introduction Wax deposition in production pipelines is one of the major flow assurance risks that need to be considered whether developing new fields or maintaining existing operations. The problems associated with wax deposition are reduced productivity, increased pressure drop and the risk of getting a pig stuck during maintenance operations. It is known that the production losses and remediation operations associated with paraffin deposition cost millions of dollars1. Flow assurance risks, including wax deposition and wax gelation, become a bigger concern as the oil industry continues to expand deepwater operations to greater depths and distances in cold environments. Precipitation of n-paraffins (waxes) is the precursor to wax deposition. The phase stability of crude oil is dependent on a multitude of factors including the composition of the oil, temperature, pressure, and other operating conditions. At reservoir pressures and temperatures, the paraffin molecules are typically fully dissolved in the reservoir fluid. As the temperature drops in the wellbore and production lines, these paraffins start precipitating out of solution due to solubility limits. It is important to distinguish between the two phenomena - precipitation and deposition. Precipitation is a necessary, but not sufficient condition for deposition. Unfortunately, this issue seems to be a bit confused in common parlance in the oil industry. Precipitation is, sometimes, incorrectly referred to as deposition. It must be noted that deposition during production operations is a more complex phenomenon than precipitation. Wax precipitation is simply a thermodynamic phenomenon that is observed when the fluid temperature is reduced below the so-called Wax Appearance Temperature (TWAT). As the fluid temperature is further reduced, more waxes precipitate out of solution, possibly leading to a point where the fluid loses mobility due to gelation. The industrial practice is to approximately measure the temperature of "no mobility" using the ASTM D97 method; this temperature is called the pour point temperature.
Published: 6 September 2018
Abstract:
The high affinity (KD∼ 10−15M) of biotin to avidin and streptavidin is the essential component in a multitude of bioassays with many experiments using biotin modifications to invoke coupling. Equilibration times suggested for these assays assume that the association rate constant (kon) is approximately diffusion limited (109M−1s−1) but recent single molecule and surface binding studies indicate they are slower than expected (105to 107M−1s−1). In this study, we asked whether these reactions in solution are diffusion controlled, what reaction model and thermodynamic cycle described the complex formation, and the functional differences between avidin and streptavidin. We have studied the biotin association by two stopped-flow methodologies using labeled and unlabeled probes: I) fluorescent probes attached to biotin and biocytin; and II) unlabeled biotin and HABA, 2-(4’-hydroxyazobenzene)-benzoic acid. Native avidin and streptavidin are homo-tetrameric and the association data show no cooperativity between the binding sites. The konvalues of streptavidin are faster than avidin but slower than expected for a diffusion limited reaction in both complexes. Moreover, the Arrhenius plots of the konvalues revealed strong temperature dependence with large activation energies (6-15 kcal/mol) that do not correspond to a diffusion limited process (3-4 kcal/mol). The data suggest that the avidin binding sites are deeper and less accessible than those of streptavidin. Accordingly, we propose a simple reaction model with a single transition state for non-immobilized reactants whose forward thermodynamic parameters complete the thermodynamic cycle in agreement with previously reported studies. Our new understanding and description of the kinetics, thermodynamics and spectroscopic parameters for these complexes will help to improve purification efficiencies, molecule detection, and drug screening assays or find new applications.
, Timothy C. Mueser, Kathia Zaleta-Rivera, Katie A. Carnes, José González-Valdez, Lawrence J. Parkhurst
Published: 28 February 2019
Journal: PLOS ONE
Abstract:
The high affinity (KD ~ 10−15 M) of biotin for avidin and streptavidin is the essential component in a multitude of bioassays with many experiments using biotin modifications to invoke coupling. Equilibration times suggested for these assays assume that the association rate constant (kon) is approximately diffusion limited (109 M-1s-1) but recent single molecule and surface binding studies indicate that they are slower than expected (105 to 107 M-1s-1). In this study, we asked whether these reactions in solution are diffusion controlled, which reaction model and thermodynamic cycle describes the complex formation, and if there are any functional differences between avidin and streptavidin. We have studied the biotin association by two stopped-flow methodologies using labeled and unlabeled probes: I) fluorescent probes attached to biotin and biocytin; and II) unlabeled biotin and HABA, 2-(4’-hydroxyazobenzene)-benzoic acid. Both native avidin and streptavidin are homo-tetrameric and the association data show no cooperativity between the binding sites. The kon values of streptavidin are faster than avidin but slower than expected for a diffusion limited reaction in both complexes. Moreover, the Arrhenius plots of the kon values revealed strong temperature dependence with large activation energies (6–15 kcal/mol) that do not correspond to a diffusion limited process (3–4 kcal/mol). Accordingly, we propose a simple reaction model with a single transition state for non-immobilized reactants whose forward thermodynamic parameters complete the thermodynamic cycle, in agreement with previously reported studies. Our new understanding and description of the kinetics, thermodynamics, and spectroscopic parameters for these complexes will help to improve purification efficiencies, molecule detection, and drug screening assays or find new applications.
Published: 1 June 2018
Abstract:
For good or evil, all physical processes observed in the Universe are subject to the laws and limitations of thermodynamics. Since the fundamental laws of thermodynamics are well understood, it is unnecessary to limit your own understanding of these thermodynamic restrictions. In this text we lay out the straightforward foundation of thermodynamics, and apply it to systems of interest to engineers and scientists. Aside from considering gases, liquids and their mixtures – traditional problems in engineering thermodynamics – we consider also the thermodynamics of DNA, proteins, polymers, and surfaces. In contrast to the approach adopted by most traditional thermodynamics texts, we begin our exposition with the fundamental postulates of thermodynamics, and rigorously derive all steps. When approximations are necessary, these are made clear. Therefore, the student will not only learn to solve some standard problems, but will also know how to approach a new problem on safe ground before making approximations. Thermodynamics gives interrelationships between the properties of matter. Often these relationships are non-intuitive. For example, by measuring the volume and heat capacity as functions of temperature and pressure, we can find all other thermodynamic properties of a pure system. Then, we can use relations between different thermodynamic properties to estimate the temperature rise of a fluid when it is expanded in an insulated container, or, we can use such data to predict the boiling point of a liquid. In Chapter 2, we introduce the necessary variables to describe a system in thermodynamic equilibrium.
, Kirill A. Komarov, Nikita P. Kryuchkov, , Vadim V. Brazhkin
Published: 7 April 2018
The Journal of Chemical Physics, Volume 148; https://doi.org/10.1063/1.5022969

Abstract:
The heat capacity of classical crystals is determined by the Dulong–Petit value CV ≃ D (where D is the spatial dimension) for softly interacting particles and has the gas-like value CV ≃ D/2 in the hard-sphere limit, while deviations are governed by the effects of anharmonicity. Soft- and hard-sphere interactions, which are associated with the enthalpy and entropy of crystals, are specifically anharmonic owing to violation of a linear relation between particle displacements and corresponding restoring forces. Here, we show that the interplay between these two types of anharmonicities unexpectedly induces two possible types of heat capacity anomalies. We studied thermodynamics, pair correlations, and collective excitations in 2D and 3D crystals of particles with a limited range of soft repulsions to prove the effect of interplay between the enthalpy and entropy types of anharmonicities. The observed anomalies are triggered by the density of the crystal, changing the interaction regime in the zero-temperature limit, and can provide about 10% excess of the heat capacity above the Dulong–Petit value. Our results facilitate understanding effects of complex anharmonicity in molecular and complex crystals and demonstrate the possibility of new effects due to the interplay between different types of anharmonicities.
S. W. Dean, L. Li, S. G. Huang, L. Wang, Y. L. He, , O. Van Der Biest
Published: 1 January 2008
Journal of Astm International, Volume 5, pp 1-8; https://doi.org/10.1520/jai101765

Abstract:
The influence of C and Al content on phase transformation temperatures is investigated by dilatometric analysis. With the new set of experimental data, an updated thermodynamic description of the Fe-Al-C system is presented, using the thermodynamic data of the limiting binaries and the parameters for the Fe-Al-C ternary system optimized by some of the present authors. A well reproduced vertical section of the Fe-Mn-Si-Al-C system is also presented according to the thermodynamic description of the lower order systems. For the development of P containing transformation induced plasticity steel, the possibility of phosphorous segregating at grain boundary is discussed by thermodynamics as well as kinetics. Lower critical temperature is estimated for the steel to obtain the starting temperature of fast cooling. To understand the minimum rate of fast cooling, pearlite growth kinetics is calculated with self-developed diffusion coefficients of elements at the grain boundary. Over-aging temperature is tentatively determined through the calculation of T0 temperature by both equilibrium and para-equilibrium assumptions.
Irving Granet, Jorge Luis Alvarado, Maurice Bluestein
Published: 17 September 2020
Abstract:
After reading and studying the material in this chapter, you should be able to Understand that work can be converted into heat, but that the conversion of heat into useful work may not always be possible. Define a heat engine as a continuously operating system across whose boundaries flow only heat and work. Define thermal efficiency as the ratio of the useful work delivered by a heat engine or cycle to the heat input to the engine or cycle. Understand what is meant by the statement that a reversible process is any process performed so that the system and all its surroundings can be restored to their initial states by performing the process in reverse. State the second law of thermodynamics as “Heat cannot of itself pass from a lower temperature to a higher temperature.” Understand that all natural processes are irreversible, and cite some of the effects that cause irreversibility. Explain the four processes that constitute the Carnot cycle. Deduce from the Carnot cycle three important general conclusions concerning the limits of the efficiency of a heat engine. Define the new property that is introduced in this chapter that we have called entropy. Understand that entropy is also a measure of the unavailability of energy that occurs in an irreversible process. Calculate the change in entropy for a process in which there is a temperature change, such as the mixing of two fluids. Understand that the entropy of an isolated system increases or, in the limit, remains the same, which, for a given internal energy, we interpret to mean that the state having the greatest entropy will be the most probable state that the system will assume. This state is called stable equilibrium. Use entropy as a property in the analysis of thermodynamic systems.202
Published: 31 May 2010
Progress in Materials Science, Volume 55, pp 247-352; https://doi.org/10.1016/j.pmatsci.2009.05.002

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, Ziyan Wang,
Published: 4 April 2017
Journal of Heat Transfer, Volume 139; https://doi.org/10.1115/1.4036086

Abstract:
Minimum entropy production principle (MEPP) is an important variational principle for the evolution of systems to nonequilibrium stationary state. However, its restricted validity in the domain of Onsager's linear theory requires an inverse temperature square-dependent thermal conductivity for heat conduction problems. A previous derivative principle of MEPP still limits to constant thermal conductivity case. Therefore, the present work aims to generalize the MEPP to remove these nonphysical limitations. A new dissipation potential is proposed, the minimum of which thus corresponds to the stationary state with no restriction on thermal conductivity. We give both rigorous theoretical verification of the new extremum principle and systematic numerical demonstration through 1D transient heat conduction with different kinds of temperature dependence of the thermal conductivity. The results show that the new principle remains always valid while MEPP and its derivative principle fail beyond their scopes of validity. The present work promotes a clear understanding of the existing thermodynamic extremum principles and proposes a new one for stationary state in nonlinear heat transport.
Published: 12 August 2009
Journal of Modern Optics, Volume 56, pp 2076-2081; https://doi.org/10.1080/09500340903078984

Abstract:
Ultra-cold atomic Fermi gases at nano-Kelvin temperatures provide a new paradigm for the foundations of quantum many-body theory. Here, we summarize our recent theoretical efforts to understand the intriguing properties of these strongly correlated Fermi gases. A number of powerful theoretical techniques have been developed, including (i) a quantitative diagrammatic theory taken to infinite order; (ii) a virial expansion at high temperature; (iii) exact solutions for one-dimensional many-body systems; and (iv) new quantum simulations using the Gaussian Fermi representation. We have employed these techniques to predict universal thermodynamics in the strongly interacting limit and exotic quantum superfluid phases with imbalanced spin populations. More insights into strongly interacting Fermi gases are anticipated, by extending the Gaussian Fermi simulations to new regimes.
Published: 15 February 2007
Information Sciences, Volume 177, pp 969-987; https://doi.org/10.1016/j.ins.2006.07.006

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Richard H. Beyler
Published: 1 January 2000
Technology and Culture, Volume 41, pp 395-396; https://doi.org/10.1353/tech.2000.0054

Abstract:
Technology and Culture 41.2 (2000) 395-396 This scientific biography of the German physical chemist Walther Nernst (1864-1941) is not a heroic tale, but instead, as its title suggests, a finely textured account of a complex transition to a new domain of research. Nernst is best known for his heat theorem, published in early 1906 and today commonly called the Third Law of Thermodynamics. The Third Law became a foundation of physical chemistry and solid-state physics. It also furnished scientists with a means to calculate chemical equilibria, a matter of immense theoretical importance and practical value. But, Diana Barkan argues, it is just these weighty consequences that obscure our understanding of how Nernst actually arrived at the heat theorem and how it was received by other scientists. In Barkan's account, Nernst's career is impossible to pigeonhole into a tidy disciplinary foundation myth, since it was specific problems and not disciplinary agendas that propelled his work. Indeed, central topics of her book are the formation of professional identities from the complex interactions of individuals and groups and the ways in which theories and practices become "canonical" for particular disciplines. The book also shows how aspects of Nernst's career often regarded as peripheral--above all, his development of a new type of incandescent lamp in the late 1890s--were in fact intimately connected to his supposedly more fundamental work in thermodynamics. Barkan thereby reveals the close association of practical technological concerns with modern physical theory around the turn of the century. After a historiographical introduction, the first chapters trace Nernst's training under Friedrich Kohlrausch, Ludwig Boltzmann, and others, and his early research on electrolytic solutions--research that brought him into sometimes contentious interaction with leading physical chemists, such as Friedrich Ostwald and Svante Arrhenius, and thermodynamicists such as Max Planck. The middle section discusses the scientific puzzles that led to [End Page 395] the heat theorem itself. Chapters on the electrolytic lamp, high-temperature physics, thermodynamic theory, and low-temperature physics each show how a particular problem led to innovations in experimental design, instrumentation, and theory that, in turn, generated new problems--all of them, however, intersecting in the behavior of specific heat across an extreme range of temperatures. Historians of technology will be particularly interested in the discussion of the "Nernst lamp," whose patents he sold to Allgemeine Elektrizitätsgesellschaft (AEG). The company had high hopes for the lamp, but it ended up a commercial failure, symbolized by a conspicuously unsuccessful display at the 1900 Paris world's fair. The final chapters of the book deal with the "canonization" of Nernst's work, looking behind the scenes at the first Solvay physics congress, which Nernst helped organize in 1911, and at his Nobel Prize award a decade later. These detailed examinations of scientists' interactions again show that the conventional meaning now attached to these events--the successful integration of thermodynamics and the new quantum theory via the Third Law--was, amid the welter of theoretical uncertainties and personal rivalries, far from clear at the time. The book does not pretend to be a complete biography. A major limitation is Nernst's apparent destruction of most of his papers before his death, although Barkan relies with agility on other archives (and, of course, published materials). Besides this external limitation, the scope of the book means that some topics cannot be fully developed--Nernst's highly controversial poison gas research during World War I, for example. There are some unfortunate editing glitches: a few personal and place names are misspelled; an acronym (BASF) is misidentified; and several items cited in the footnotes do not appear in the bibliography, thus obscuring the documentation of sources. But these are minor flaws in an otherwise quite informative and thoughtfully constructed book that should be relevant to anyone interested in the...
Subrata Ghose
Published: 1 January 1975
Reviews of Geophysics, Volume 13, pp 81-87; https://doi.org/10.1029/rg013i003p00081

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, Hamid Abdollahi, Tsyuoshi Minami, Ben Peco, Sean Reliford
Published: 21 December 2021
Frontiers in Chemistry, Volume 9; https://doi.org/10.3389/fchem.2021.759714

Abstract:
The power of sensing molecules is often characterized in part by determining their thermodynamic/dynamic properties, in particular the binding constant of a guest to a host. In many studies, traditional nonlinear regression analysis has been used to determine the binding constants, which cannot be applied to complex systems and limits the reliability of such calculations. Supramolecular sensor systems include many interactions that make such chemical systems complicated. The challenges in creating sensing molecules can be significantly decreased through the availability of detailed mathematical models of such systems. Here, we propose uncovering accurate thermodynamic parameters of chemical reactions using better-defined mathematical modeling-fitting analysis is the key to understanding molecular assemblies and developing new bio/sensing agents. The supramolecular example we chose for this investigation is a self-assembled sensor consists of a synthesized receptor, DPA (DPA = dipicolylamine)-appended phenylboronic acid (1) in combination with Zn2+(1.Zn) that forms various assemblies with a fluorophore like alizarin red S (ARS). The self-assemblies can detect multi-phosphates like pyrophosphate (PPi) in aqueous solutions. We developed a mathematical model for the simultaneous quantitative analysis of twenty-seven intertwined interactions and reactions between the sensor (1.Zn-ARS) and the target (PPi) for the first time, relying on the Newton-Raphson algorithm. Through analyzing simulated potentiometric titration data, we describe the concurrent determination of thermodynamic parameters of the different guest-host bindings. Various values of temperatures, initial concentrations, and starting pHs were considered to predict the required measurement conditions for thermodynamic studies. Accordingly, we determined the species concentrations of different host-guest bindings in a generalized way. This way, the binding capabilities of a set of species can be quantitatively examined to systematically measure the power of the sensing system. This study shows analyzing supramolecular self-assemblies with solid mathematical models has a high potential for a better understanding of molecular interactions within complex chemical networks and developing new sensors with better sensing effects for bio-purposes.
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