WorldWideScience

Sample records for bulges thermodynamic consequences

  1. Thermodynamic examination of 1- to 5-nt purine bulge loops in RNA and DNA constructs

    Science.gov (United States)

    Strom, Shane; Shiskova, Evgenia; Hahm, Yaeeun

    2015-01-01

    Bulge loops are common features of RNA structures that are involved in the formation of RNA tertiary structures and are often sites for interactions with proteins and ions. Minimal thermodynamic data currently exist on the bulge size and sequence effects. Using thermal denaturation methods, thermodynamic properties of 1- to 5-nt adenine and guanine bulge loop constructs were examined in 10 mM MgCl2 or 1 M KCl. The ΔG37∘ loop parameters for 1- to 5-nt purine bulge loops in RNA constructs were between 3.07 and 5.31 kcal/mol in 1 M KCl buffer. In 10 mM magnesium ions, the ΔΔG° values relative to 1 M KCl were 0.47–2.06 kcal/mol more favorable for the RNA bulge loops. The ΔG37∘ loop parameters for 1- to 5-nt purine bulge loops in DNA constructs were between 4.54 and 5.89 kcal/mol. Only 4- and 5-nt guanine constructs showed significant change in stability for the DNA constructs in magnesium ions. A linear correlation is seen between the size of the bulge loop and its stability. New prediction models are proposed for 1- to 5-nt purine bulge loops in RNA and DNA in 1 M KCl. We show that a significant stabilization is seen for small bulge loops in RNA in the presence of magnesium ions. A prediction model is also proposed for 1- to 5-nt purine bulge loop RNA constructs in 10 mM magnesium chloride. PMID:26022248

  2. Thermodynamic examination of 1- to 5-nt purine bulge loops in RNA and DNA constructs.

    Science.gov (United States)

    Strom, Shane; Shiskova, Evgenia; Hahm, Yaeeun; Grover, Neena

    2015-07-01

    Bulge loops are common features of RNA structures that are involved in the formation of RNA tertiary structures and are often sites for interactions with proteins and ions. Minimal thermodynamic data currently exist on the bulge size and sequence effects. Using thermal denaturation methods, thermodynamic properties of 1- to 5-nt adenine and guanine bulge loop constructs were examined in 10 mM MgCl(2) or 1 M KCl. The [Formula: see text] loop parameters for 1- to 5-nt purine bulge loops in RNA constructs were between 3.07 and 5.31 kcal/mol in 1 M KCl buffer. In 10 mM magnesium ions, the ΔΔG° values relative to 1 M KCl were 0.47-2.06 kcal/mol more favorable for the RNA bulge loops. The [Formula: see text] loop parameters for 1- to 5-nt purine bulge loops in DNA constructs were between 4.54 and 5.89 kcal/mol. Only 4- and 5-nt guanine constructs showed significant change in stability for the DNA constructs in magnesium ions. A linear correlation is seen between the size of the bulge loop and its stability. New prediction models are proposed for 1- to 5-nt purine bulge loops in RNA and DNA in 1 M KCl. We show that a significant stabilization is seen for small bulge loops in RNA in the presence of magnesium ions. A prediction model is also proposed for 1- to 5-nt purine bulge loop RNA constructs in 10 mM magnesium chloride. © 2015 Strom et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  3. Galactic bulges

    CERN Document Server

    Peletier, Reynier; Gadotti, Dimitri

    2016-01-01

    This book consists of invited reviews on Galactic Bulges written by experts in the field. A central point of the book is that, while in the standard picture of galaxy formation a significant amount of the baryonic mass is expected to reside in classical bulges, the question what is the fraction of galaxies with no classical bulges in the local Universe has remained open. The most spectacular example of a galaxy with no significant classical bulge is the Milky Way. The reviews of this book attempt to clarify the role of the various types of bulges during the mass build-up of galaxies, based on morphology, kinematics, and stellar populations, and connecting their properties at low and high redshifts. The observed properties are compared with the predictions of the theoretical models, accounting for the many physical processes leading to the central mass concentration and their destruction in galaxies. This book serves as an entry point for PhD students and non-specialists and as a reference work for researchers...

  4. Thermodynamics

    CERN Document Server

    Fermi, Enrico

    1956-01-01

    Indisputably, this is a modern classic of science. Based on a course of lectures delivered by the author at Columbia University, the text is elementary in treatment and remarkable for its clarity and organization. Although it is assumed that the reader is familiar with the fundamental facts of thermometry and calorimetry, no advanced mathematics beyond calculus is assumed.Partial contents: thermodynamic systems, the first law of thermodynamics (application, adiabatic transformations), the second law of thermodynamics (Carnot cycle, absolute thermodynamic temperature, thermal engines), the entr

  5. Is thermodynamic irreversibility a consequence of the expansion of the Universe?

    Science.gov (United States)

    Osváth, Szabolcs

    2018-02-01

    This paper explains thermodynamic irreversibility by applying the expansion of the Universe to thermodynamic systems. The effect of metric expansion is immeasurably small on shorter scales than intergalactic distances. Multi-particle systems, however, are chaotic, and amplify any small disturbance exponentially. Metric expansion gives rise to time-asymmetric behaviour in thermodynamic systems in a short time (few nanoseconds in air, few ten picoseconds in water). In contrast to existing publications, this paper explains without any additional assumptions the rise of thermodynamic irreversibility from the underlying reversible mechanics of particles. Calculations for the special case which assumes FLRW metric, slow motions (v ≪ c) and approximates space locally by Euclidean space show that metric expansion causes entropy increase in isolated systems. The rise of time-asymmetry, however, is not affected by these assumptions. Any influence of the expansion of the Universe on the local metric causes a coupling between local mechanics and evolution of the Universe.

  6. Hidden bars and boxy bulges

    NARCIS (Netherlands)

    Merrifield, MR; Kuijken, K

    It has been suggested that the boxy and peanut-shaped bulges found in some edge-on galaxies are galactic bars viewed from the side. We investigate this hypothesis by presenting emission-line spectra for a sample of 10 edge-on galaxies that display a variety of bulge morphologies. To avoid potential

  7. Chemical buffering in natural and engineered barrier systems: Thermodynamic constraints and performance assessment consequences

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, R.C.; Wei Zhou [Monitor Scientific, LLC, Denver, CO (United States)

    2000-12-01

    Thermodynamic and kinetic constraints on the chemical buffering properties of natural and engineered-barrier systems are derived in this study from theoretical descriptions, incorporated in the reaction-path model, of reversible and irreversible mass transfer in multicomponent, multiphase systems. The buffering properties of such systems are conditional properties because they refer to a specific aqueous species in a system that is open with respect to a specific reactant. The solution to a mathematical statement of this concept requires evaluation of the dependence of the activity of the buffered species on incremental changes in the overall reaction-progress variable. This dependence can be represented by a truncated Taylor's series expansion, where the values of associated derivatives are calculated using finite-difference techniques and mass-balance, charge-balance and mass-action constraints. Kinetic constraints on buffering behavior can also be described if the relation between reactant flux and reaction rate is well defined. This relation is explicit for the important case of advective groundwater flow and water-rock interaction. We apply the theoretical basis of the chemical buffering concept to processes that could affect the performance of a deep geologic repository for nuclear waste. Specifically, we focus on the likelihood that an inverse relation must exist between the buffer intensity and the migration velocity of reaction fronts in systems involving advective or diffusive mass transport. A quantitative understanding of this relation would provide the basis for evaluating the potential role of chemical buffering in achieving the isolation and retardation functions, of the EBS and geosphere in a KBS-3 repository. Our preliminary evaluation of this role considers the effects of chemical buffering on the propagation velocity of a pH front in both the near- and far field. We use a geochemical modeling technique compatible with the reaction-path model

  8. Coherence-limited solar power conversion: the fundamental thermodynamic bounds and the consequences for solar rectennas

    Science.gov (United States)

    Mashaal, Heylal; Gordon, Jeffrey M.

    2014-10-01

    Solar rectifying antennas constitute a distinct solar power conversion paradigm where sunlight's spatial coherence is a basic constraining factor. In this presentation, we derive the fundamental thermodynamic limit for coherence-limited blackbody (principally solar) power conversion. Our results represent a natural extension of the eponymous Landsberg limit, originally derived for converters that are not constrained by the radiation's coherence, and are irradiated at maximum concentration (i.e., with a view factor of unity to the solar disk). We proceed by first expanding Landsberg's results to arbitrary solar view factor (i.e., arbitrary concentration and/or angular confinement), and then demonstrate how the results are modified when the converter can only process coherent radiation. The results are independent of the specific power conversion mechanism, and hence are valid for diffraction-limited as well as quantum converters (and not just classical heat engines or in the geometric optics regime). The derived upper bounds bode favorably for the potential of rectifying antennas as potentially high-efficiency solar converters.

  9. Anomalous bulging behaviors of a dielectric elastomer balloon under internal pressure and electric actuation

    Science.gov (United States)

    Wang, Fangfang; Yuan, Chao; Lu, Tongqing; Wang, T. J.

    2017-05-01

    When a clamped membrane of elastomer is subject to a lateral pressure, it bulges into a hemispherical balloon. However, for a clamped membrane of dielectric elastomer (DE) under a lateral pressure as well as a voltage through the thickness, it may bulge into a regular hemispherical balloon or an irregular shape. This work focuses on the anomalous bulging behaviors (i.e. the irregular bulging shape) of a DE balloon under electromechanical coupling loading. The full set of the equilibrium configurations of the DE balloon is theoretically derived within the framework of thermodynamics, based on which we find that with the increase of the applied voltage, the pressure-volume relationship changes from the single-N shape for the case of purely mechanical loading to a double-N shape, where five or more equilibrium configurations exist including both regular and irregular bulging shapes. Through stability analysis we find that the anomalous bulging is a common behavior for the DE balloon under electromechanical coupling loading and all types of irregular bulging shapes can be achieved by following carefully designed loading paths. Besides, the irregular bulging region usually has the largest local strain which may initiate the failure of the DE membrane. Guided by the theoretical analysis, we conducted experiments on a DE balloon under the internal pressure and electrical actuation. Typical irregular shapes were successfully observed and the entire evolution of the shape changing agrees very well with theoretical predictions. These findings enrich understandings of highly nonlinear behaviors for soft materials under electromechanical coupling loading.

  10. Climate Change and its Potential Consequences to the Thermodynamics of an Alpine Lake

    Science.gov (United States)

    Fink, G.

    2012-04-01

    The characteristics of mixing processes as well as duration, frequency, and stability of an alpine lake's stratification are strongly coupled to the local climate conditions. These physical processes then again define the way in which life - from bacteria to human being - develops in this environment. Hence, probably economic and cultural lake uses are affected by climate change. Studies discovered reactions of lake physics due to global warming in central Europe in measured time series. The question is: What changes in alpine lake's thermodynamic processes do we have to expect in the next decades? This question is directed at first to general lake properties like water temperature, metalimnion depth, and heat balance and their behavior in space and time. Secondly, there is a need for information about mixing processes in these monomictic lakes. Mixing is important for the distribution of e.g. nutrients and oxygen. Thus, it is necessary to know how mixing intensity changes under likely future climate conditions. For this purpose three representative lakes were selected: Lake Constance (international), Lago di Viverone (Italy), and Woerthersee (Austria). For each lake a 1dv hydrodynamic model was built up, calibrated with an evolutionary algorithm, and finally validated. The model's source code is in an experimental state and it was provided by Deltares (Netherlands). During calibration the calculated mean monthly temperatures in different depths were compared to measurements. Then, based upon measured meteorological data "what if"-scenarios of air temperature, wind speed, cloud cover and relative humidity were developed by changing the mean value or by removing the old trend and adding a new one. When driving the model with this broad range of meteorology the result is a sensitivity study. This allows the determination of the lake's sensitivity e.g. regarding mixing intensity on changing climate, in a way that is independent from rough regional climate projections

  11. Youth bulges and youth unemployment

    OpenAIRE

    David Lam

    2014-01-01

    The youth population bulge is often mentioned in discussions of youth unemployment and unrest in developing countries, most recently in explaining the “Arab Spring.” But the youth share of the population has fallen rapidly in recent decades in most countries, and is projected to continue to fall. Evidence on the link between youth population bulges and youth unemployment is mixed. It should not be assumed that declines in the relative size of the youth population will translate into falling y...

  12. Stellar Feedback from Galactic Bulges

    Science.gov (United States)

    Tang, Shikui; Wang, D. Q.

    2009-01-01

    We demonstrate that feedback from galactic bulges can play an essential role in the halo gas dynamics and the evolution of their host galaxies by conducting a series of 1-D and 3-D simulations. In our 1-D models we approximately divide the the bulge stellar feedback into two phases: 1) a starbusrt-induced blastwave from the formation of bulge built up through frequent major mergers at high redshift and 2) a gradual feedback in forms of stellar wind and Type Ia SNe from low mass stars. Our simulations show that the combination of the two-phase feedback can heat the surrounding gas beyond the virial radius and stop further gas accretion, which naturally produces a baryon deficit around MW-like galaxies and explains the lack of large-scale X-ray halos, consistent with observations. The hot gas dynamics depends sensitively on the environment and bulge formation history. This dependency may account for the large dispersion in the X-ray luminosities of the galaxies with similar L_B. In the 3-D simulations, we examine the spatial, thermal, and chemical substructures and their effects on X-ray measurements. The sporadic SN explosion creates wealth of filamentary and shell-like structures in the hot gas and produces a broad lognormal-like emission-measure distribution, which enhances the X-ray emission at a low and high temperatures. The luminosity at 0.3-2.0 keV band is nearly tripled due to the gas structures. We find that the SN Ia ejecta are not well-mixed with the ambient medium within the bulge scale, and the X-ray emission is primarily from shocked stellar wind materials which in general has low metallicity.

  13. The multicomponent structure of bulges

    Science.gov (United States)

    Dettmar, Ralf-Juergen; Krenz, Thomas; Barteldrees, Andreas

    1993-01-01

    The morphology of disk galaxies is usually described by two major components, the centrally concentrated spheroidal component, called the bulge, and an oblate disk. The ratio of there contribution to the total luminosity - the bulge-to-disk ratio - is one of the parameters characterizing the Hubble sequence. Following de Vaucouleurs (1948), for most galaxies the radial distribution of the outer spheroid is fairly well described by the r exp 1/4 law I(r)=I(sub 0) exp(-(alpha)r), whereas the radial luminosity distribution of the disk follows an exponential law: I(r)=I(sub 0) exp(-alpha(r exp 1/4)) (Freeman 1970), with r the radial distance from the center. I(sub 0) and alpha are characteristic constants for each individual galaxy. Parameters for the structural properties of these components give important constraints for models of the formation and evolution of galaxies. Therefore we have tried to decompose disk and bulge components from high S/N CCD observations of a sample of edge-on disk galaxies. A common procedure for the decomposition is to model one component in a region where it dominates and subtract it from the combined light distribution. This technique was successfully carried out e.g. by van der Kruit & Earl (1981, 1982) and Wakamatsu & Hamabe (1984, 1989). Here we present two more examples of bulge-dominated edge-on SO galaxies, namely ESO 506-G33 and NGC 7123, which show an additional small and concentrated central component besides disk and 'bulge'.

  14. Improved Model for Predicting the Free Energy Contribution of Dinucleotide Bulges to RNA Duplex Stability.

    Science.gov (United States)

    Tomcho, Jeremy C; Tillman, Magdalena R; Znosko, Brent M

    2015-09-01

    Predicting the secondary structure of RNA is an intermediate in predicting RNA three-dimensional structure. Commonly, determining RNA secondary structure from sequence uses free energy minimization and nearest neighbor parameters. Current algorithms utilize a sequence-independent model to predict free energy contributions of dinucleotide bulges. To determine if a sequence-dependent model would be more accurate, short RNA duplexes containing dinucleotide bulges with different sequences and nearest neighbor combinations were optically melted to derive thermodynamic parameters. These data suggested energy contributions of dinucleotide bulges were sequence-dependent, and a sequence-dependent model was derived. This model assigns free energy penalties based on the identity of nucleotides in the bulge (3.06 kcal/mol for two purines, 2.93 kcal/mol for two pyrimidines, 2.71 kcal/mol for 5'-purine-pyrimidine-3', and 2.41 kcal/mol for 5'-pyrimidine-purine-3'). The predictive model also includes a 0.45 kcal/mol penalty for an A-U pair adjacent to the bulge and a -0.28 kcal/mol bonus for a G-U pair adjacent to the bulge. The new sequence-dependent model results in predicted values within, on average, 0.17 kcal/mol of experimental values, a significant improvement over the sequence-independent model. This model and new experimental values can be incorporated into algorithms that predict RNA stability and secondary structure from sequence.

  15. Dust properties in the Galactic bulge

    NARCIS (Netherlands)

    Pottasch, S. R.; Bernard-Salas, J.

    Context. It has been suggested that the ratio of total-to-selective extinction R-V in dust in the interstellar medium differs in the Galactic bulge from its value in the local neighborhood. Aims. We attempt to test this suggestion. Methods. The mid-infrared hydrogen lines in 16 Galactic bulge PNe

  16. Ultrasonographic findings in patients with peristomal bulging

    DEFF Research Database (Denmark)

    Sjödahl, Rune I; Thorelius, Lars; Hallböök, Olof J

    2011-01-01

    The aim of this study was to obtain a classification of peristomal bulging based on findings at ultrasonography in patients with a sigmoid colostomy.......The aim of this study was to obtain a classification of peristomal bulging based on findings at ultrasonography in patients with a sigmoid colostomy....

  17. Role of the CCA bulge of prohead RNA of bacteriophage ø29 in DNA packaging.

    Science.gov (United States)

    Zhao, Wei; Morais, Marc C; Anderson, Dwight L; Jardine, Paul J; Grimes, Shelley

    2008-11-14

    The oligomeric ring of prohead RNA (pRNA) is an essential component of the ATP-driven DNA packaging motor of bacteriophage ø29. The A-helix of pRNA binds the DNA translocating ATPase gp16 (gene product 16) and the CCA bulge in this helix is essential for DNA packaging in vitro. Mutation of the bulge by base substitution or deletion showed that the size of the bulge, rather than its sequence, is primary in DNA packaging activity. Proheads reconstituted with CCA bulge mutant pRNAs bound the packaging ATPase gp16 and the packaging substrate DNA-gp3, although DNA translocation was not detected with several mutants. Prohead/bulge-mutant pRNA complexes with low packaging activity had a higher rate of ATP hydrolysis per base pair of DNA packaged than proheads with wild-type pRNA. Cryoelectron microscopy three-dimensional reconstruction of proheads reconstituted with a CCA deletion pRNA showed that the protruding pRNA spokes of the motor occupy a different position relative to the head when compared to particles with wild-type pRNA. Therefore, the CCA bulge seems to dictate the orientation of the pRNA spokes. The conformational changes observed for this mutant pRNA may affect gp16 conformation and/or subsequent ATPase-DNA interaction and, consequently, explain the decreased packaging activity observed for CCA mutants.

  18. CONFORMATIONAL EQUILIBRIA OF BULGED SITES IN DUPLEX DNA STUDIED BY EPR SPECTROSCOPY

    OpenAIRE

    Smith, Alyssa L.; Cekan, Pavol; Brewood, Greg P.; Okonogi, Tamara M.; Alemayehu, Saba; Hustedt, Eric J.; Benight, Albert S.; Sigurdsson, Snorri Th.; Robinson, Bruce H.

    2009-01-01

    Conformational flexibility in nucleic acids provides a basis for complex structures, binding, and signaling. One-base bulges directly neighboring single-base mismatches in nucleic acids can be present in a minimum of two distinct conformations, complicating the examination of the thermodynamics by calorimetry or UV-monitored melting techniques. To provide additional information about such structures, we demonstrate how electron paramagnetic resonance (EPR) active spin-labeled base analogues, ...

  19. Kinematic Signatures of Bulges Correlate with Bulge Morphologies and Sérsic Index

    Science.gov (United States)

    Fabricius, Maximilian H.; Saglia, Roberto P.; Fisher, David B.; Drory, Niv; Bender, Ralf; Hopp, Ulrich

    2012-07-01

    We use the Marcario Low Resolution Spectrograph at the Hobby-Eberly Telescope to study the kinematics of pseudobulges and classical bulges in the nearby universe. We present major axis rotational velocities, velocity dispersions, and h 3 and h 4 moments derived from high-resolution (σinst ≈ 39 km s-1) spectra for 45 S0 to Sc galaxies; for 27 of the galaxies we also present minor axis data. We combine our kinematics with bulge-to-disk decompositions. We demonstrate for the first time that purely kinematic diagnostics of the bulge dichotomy agree systematically with those based on Sérsic index. Low Sérsic index bulges have both increased rotational support (higher v/σ values) and on average lower central velocity dispersions. Furthermore, we confirm that the same correlation also holds when visual morphologies are used to diagnose bulge type. The previously noted trend of photometrically flattened bulges to have shallower velocity dispersion profiles turns out to be significant and systematic if the Sérsic index is used to distinguish between pseudobulges and classical bulges. The anti-correlation between h 3 and v/σ observed in elliptical galaxies is also observed in intermediate-type galaxies, irrespective of bulge type. Finally, we present evidence for formerly undetected counter-rotation in the two systems NGC 3945 and NGC 4736. This paper includes data taken at The McDonald Observatory of The University of Texas at Austin.

  20. Does the Galactic Bulge Have Fewer Planets?

    Science.gov (United States)

    Kohler, Susanna

    2016-12-01

    The Milky Ways dense central bulge is a very different environment than the surrounding galactic disk in which we live. Do the differences affect the ability of planets to form in the bulge?Exploring Galactic PlanetsSchematic illustrating how gravitational microlensing by an extrasolar planet works. [NASA]Planet formation is a complex process with many aspects that we dont yet understand. Do environmental properties like host star metallicity, the density of nearby stars, or the intensity of the ambient radiation field affect the ability of planets to form? To answer these questions, we will ultimately need to search for planets around stars in a large variety of different environments in our galaxy.One way to detect recently formed, distant planets is by gravitational microlensing. In this process, light from a distant source star is bent by a lens star that is briefly located between us and the source. As the Earth moves, this momentary alignment causes a blip in the sources light curve that we can detect and planets hosted by the lens star can cause an additional observable bump.Artists impression of the Milky Way galaxy. The central bulge is much denserthan the surroundingdisk. [ESO/NASA/JPL-Caltech/M. Kornmesser/R. Hurt]Relative AbundancesMost source stars reside in the galactic bulge, so microlensing events can probe planetary systems at any distance between the Earth and the galactic bulge. This means that planet detections from microlensing could potentially be used to measure the relative abundances of exoplanets in different parts of our galaxy.A team of scientists led by Matthew Penny, a Sagan postdoctoral fellow at Ohio State University, set out to do just that. The group considered a sample of 31 exoplanetary systems detected by microlensing and asked the following question: are the planet abundances in the galactic bulge and the galactic disk the same?A Paucity of PlanetsTo answer this question, Penny and collaborators derived the expected

  1. EXPLORING THE UNUSUALLY HIGH BLACK-HOLE-TO-BULGE MASS RATIOS IN NGC 4342 AND NGC 4291: THE ASYNCHRONOUS GROWTH OF BULGES AND BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    Bogdan, Akos; Forman, William R.; Kraft, Ralph P.; Li, Zhiyuan; Vikhlinin, Alexey; Nulsen, Paul E. J.; Jones, Christine [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Zhuravleva, Irina; Churazov, Eugene [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-str. 1, 85741 Garching bei Muenchen (Germany); Mihos, J. Christopher; Harding, Paul [Department of Astronomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 (United States); Guo, Qi [Partner Group of the Max Planck Institute for Astrophysics, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Schindler, Sabine, E-mail: abogdan@cfa.harvard.edu [Institut fuer Astro- und Teilchenphysik, Universitaet Innsbruck, Technikerstrasse 25, 6020 Innsbruck (Austria)

    2012-07-10

    We study two nearby early-type galaxies, NGC 4342 and NGC 4291, that host unusually massive black holes relative to their low stellar mass. The observed black-hole-to-bulge mass ratios of NGC 4342 and NGC 4291 are 6.9{sup +3.8}{sub -2.3}% and 1.9% {+-} 0.6%, respectively, which significantly exceed the typical observed ratio of {approx}0.2%. As a consequence of the exceedingly large black-hole-to-bulge mass ratios, NGC 4342 and NGC 4291 are Almost-Equal-To 5.1{sigma} and Almost-Equal-To 3.4{sigma} outliers from the M{sub .}-M{sub bulge} scaling relation, respectively. In this paper, we explore the origin of the unusually high black-hole-to-bulge mass ratio. Based on Chandra X-ray observations of the hot gas content of NGC 4342 and NGC 4291, we compute gravitating mass profiles, and conclude that both galaxies reside in massive dark matter halos, which extend well beyond the stellar light. The presence of dark matter halos around NGC 4342 and NGC 4291 and a deep optical image of the environment of NGC 4342 indicate that tidal stripping, in which {approx}> 90% of the stellar mass was lost, cannot explain the observed high black-hole-to-bulge mass ratios. Therefore, we conclude that these galaxies formed with low stellar masses, implying that the bulge and black hole did not grow in tandem. We also find that the black hole mass correlates well with the properties of the dark matter halo, suggesting that dark matter halos may play a major role in regulating the growth of the supermassive black holes.

  2. Most pseudo-bulges can be formed at later stages of major mergers

    Science.gov (United States)

    Sauvaget, T.; Hammer, F.; Puech, M.; Yang, Y. B.; Flores, H.; Rodrigues, M.

    2018-01-01

    Most giant spiral galaxies have pseudo or disc-like bulges that are considered to be the result of purely secular processes. This may challenge the hierarchical scenario predicting about one major merger per massive galaxy (>3 × 1010 M⊙) since the last ∼9 billion years. Here, we verify whether or not the association between pseudo-bulges and secular processes is irrevocable. Using GADGET2 N-body/SPH simulations, we have conducted a systematic study of remnants of major mergers for which progenitors have been selected (1) to follow the gas richness-look back time relationship, and (2) with a representative distribution of orbits and spins in a cosmological frame. Analysing the surface mass density profile of both nearby galaxies and merger remnants with two components, we find that most of them show pseudo-bulges or bar dominated centres. Even if some orbits lead to classical bulges just after the fusion, the contamination by the additional gas that gradually accumulates to the centre and forming stars later on, leads to remnants apparently dominated by pseudo-bulges. We also found that simple smoothed particle hydrodynamics (SPH) simulations should be sufficient to form realistic spiral galaxies as remnants of ancient gas-rich mergers without the need for specifically tuned feedback conditions. We then conclude that pseudo-bulges and bars in spiral galaxies are natural consequences of major mergers when they are realized in a cosmological context, i.e. with gas-rich progenitors as expected when selected in the distant Universe.

  3. Atmospheric Bulges on Tidally-Locked Satellites

    Science.gov (United States)

    Oza, Apurva V.; Johnson, Robert E.; Leblanc, Francois

    2017-10-01

    We use a simple analytic model to examine the spatial distribution of a volatile species in a surface-bounded atmosphere on a rotating object that is tidally-locked to its parent body. Spatial asymmetries in such atmospheres have recently been observed via ultraviolet auroral emissions from the exospheres of the icy satellites Europa and Ganymede. The Hubble Space Telescope observations indicate that these satellites host unique, surface-bounded O2 exospheres which bulge towards dusk. Using a simple 1-D mass conservation balance we examine the nature of the volatile source, the surface temperature profile, the spatial morphology of the loss process, and the adsorption and desorption properties of the surfaces to understand the spatial distribution of the surface-bounded atmosphere for a number of objects. Since the ballistic hop distances are much smaller than the satellite radii, we show that the observed asymmetries at Europa and Ganymede can be simply due to a strongly thermally-dependent source, although asymmetries in the plasma-induced loss could contribute. A key condition for these atmospheric bulges that are shifted towards dusk is the relationship between the rotation rate and the atmospheric loss rate.

  4. Enzyme oscillation can enhance the thermodynamic efficiency of cellular metabolism: Consequence of anti-phase coupling between reaction flux and affinity

    CERN Document Server

    Himeoka, Yusuke

    2015-01-01

    Cells generally convert nutrient resources to useful products via energy transduction. Accordingly, the thermodynamic efficiency of this conversion process is one of the most essential characteristics of living organisms. However, although these processes occur under conditions of dynamic metabolism, most studies of cellular thermodynamic efficiency have been restricted to examining steady states; thus, the relevance of dynamics to this efficiency has not yet been elucidated. Here, we develop a simple model of metabolic reactions with anabolism-catabolism coupling catalysed by enzymes. Through application of external oscillation in the enzyme abundances, the thermodynamic efficiency of metabolism was found to be improved. This result is in strong contrast with that observed in the oscillatory input, in which the efficiency always decreased with oscillation. This improvement was effectively achieved by separating the anabolic and catabolic reactions, which tend to disequilibrate each other, and taking advantag...

  5. Bulging anterior fontanelle: an unusual presenting sign of nutritional ...

    African Journals Online (AJOL)

    Aim: To report the first case series of infants with nutritional rickets who presented with bulging anterior fontanelle. Methods: infants who were admitted to Alrass General Hospital, Qassim, Saudi Arabia, between October 2004 and October 2007, with bulging anterior fontanelle and later found to have nutritional rickets were ...

  6. Surface photometry of bulge dominated low surface brightness galaxies

    NARCIS (Netherlands)

    Beijersbergen, M; de Blok, WJG; van der Hulst, JM

    1999-01-01

    We present results of broad band BVRI observations of a sample of galaxies with a low surface brightness (LSB) disk and a bulge. These galaxies are well described as exponential disks and exponential bulges with no preferred value for either scale length or central surface brightness. The median B

  7. The formation of the Galactic bulge of the Milky Way

    Directory of Open Access Journals (Sweden)

    Freeman K.

    2012-02-01

    Full Text Available We aim to determine if the bulge formed via mergers as predicted by Cold Dark Matter (CDM theory, or from disk instabilities, as suggested by its boxy shape, or both processes. We are observing about 28,000 bulge stars in fields that span longitudes of − 31 to + 26° and latitudes of − 5° to − 10°, targeting mostly red clump giants and we are measuring stellar velocities and chemical abundances. We have almost concluded our observations and have analysed data of 23,000 stars. We find a cylindrical rotation profile for the bulge which blends smoothly out into the disk and from the [Fe/H] results we find the bulge to be comprised of separate components, with an underlying slowly rotating metal poor subsample which we believe to be the inner halo stars and metal weak thick disk. We find only a small [Fe/H] gradient with latitude in the bulge, of − 0.07dex/kpc. This weak gradient does not necessarily support a merger origin for our bulge and the composite nature of the bulge is consistent with formation out of the thin disk as per instability formation models.

  8. The gravitational self-interaction of the Earth's tidal bulge

    Science.gov (United States)

    Norsen, Travis; Dreese, Mackenzie; West, Christopher

    2017-09-01

    According to a standard, idealized analysis, the Moon would produce a 54 cm equilibrium tidal bulge in the Earth's oceans. This analysis omits many factors (beyond the scope of the simple idealized model) that dramatically influence the actual height and timing of the tides at different locations, but it is nevertheless an important foundation for more detailed studies. Here, we show that the standard analysis also omits another factor—the gravitational interaction of the tidal bulge with itself—which is entirely compatible with the simple, idealized equilibrium model and which produces a surprisingly non-trivial correction to the predicted size of the tidal bulge. Our analysis uses ideas and techniques that are familiar from electrostatics, and should thus be of interest to teachers and students of undergraduate E&M, Classical Mechanics (and/or other courses that cover the tides), and geophysics courses that cover the closely related topic of Earth's equatorial bulge.

  9. Triangular mattress suture in abdominal diastasis to prevent epigastric bulging.

    Science.gov (United States)

    Ferreira, L M; Castilho, H T; Hochberg, J; Ardenghy, M; Toledo, S R; Cruz, R G; Tardelli, H

    2001-02-01

    In the classic abdominoplasty, the treatment of large diastasis recti with simple or vertical mattress sutures may result in a nonaesthetic bulge. The surgeon may produce a craniocaudal bulge deformity by treating the flaccidity in the horizontal plane only, although it occurs in all directions. The authors describe the triangular mattress suture for the treatment of large diastasis recti, and demonstrate the mechanism involved in producing an epigastric bulge. Also presented is their clinical experience with 56 patients, with a 3-year follow-up, using this new plication method. The triangular mattress suture is a simple, quick, and effective way to correct abdominal diastasis and to avoid the epigastric bulge deformity with no added morbidity.

  10. Galaxies Grow Their Bulges and Black Holes in Diverse Ways

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Eric F.; Harmsen, Benjamin; D’Souza, Richard [Department of Astronomy, University of Michigan, 1085 South University Avenue, Ann Arbor, MI 48109-1107 (United States); Monachesi, Antonela [Max Planck Institut für Astrophysik, Karl-Schwarzschild-Str. 1, Postfach 1317, D-85741 Garching (Germany); Jong, Roelof S. de [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Bailin, Jeremy [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487-0324 (United States); Radburn-Smith, David J. [Department of Astronomy, University of Washington, 3910 15th Avenue NE, Seattle, WA 98195 (United States); Holwerda, Benne W., E-mail: ericbell@umich.edu [Department of Physics and Astronomy, University of Louisville, 102 Natural Science Building, Louisville, KY 40292 (United States)

    2017-03-01

    Galaxies with Milky Way–like stellar masses have a wide range of bulge and black hole masses; in turn, these correlate with other properties such as star formation history. While many processes may drive bulge formation, major and minor mergers are expected to play a crucial role. Stellar halos offer a novel and robust measurement of galactic merger history; cosmologically motivated models predict that mergers with larger satellites produce more massive, higher-metallicity stellar halos, reproducing the recently observed stellar halo metallicity–mass relation. We quantify the relationship between stellar halo mass and bulge or black hole prominence using a sample of 18 Milky Way-mass galaxies with newly available measurements of (or limits on) stellar halo properties. There is an order of magnitude range in bulge mass, and two orders of magnitude in black hole mass, at a given stellar halo mass (or, equivalently, merger history). Galaxies with low-mass bulges show a wide range of quiet merger histories, implying formation mechanisms that do not require intense merging activity. Galaxies with massive “classical” bulges and central black holes also show a wide range of merger histories. While three of these galaxies have massive stellar halos consistent with a merger origin, two do not—merging appears to have had little impact on making these two massive “classical” bulges. Such galaxies may be ideal laboratories to study massive bulge formation through pathways such as early gas-rich accretion, violent disk instabilities, or misaligned infall of gas throughout cosmic time.

  11. Process optimization of joining by upset bulging with local heating

    Science.gov (United States)

    Rusch, Michael; Almohallami, Amer; Sviridov, Alexander; Bonk, Christian; Behrens, Bernd-Arno; Bambach, Markus

    2017-10-01

    Joining by upset bulging is a mechanical joining method where axial load is applied to a tube to form two revolving bulges, which clamp the parts to be joined and create a force and form fit. It can be used to join tubes with other structures such as sheets, plates, tubes or profiles of the same or different materials. Other processes such as welding are often limited in joining multi-material assemblies or high-strength materials. With joining by upset bulging at room temperature, the main drawback is the possible initiation of damage (cracks) in the inner buckling zone because of high local stresses and strains. In this paper, a method to avoid the formation of cracks is introduced. Before forming the bulge the tube is locally heated by an induction coil. For the construction steel (E235+N) a maximum temperature of 700 °C was used to avoid phase transformation. For the numerical study of the process the mechanical properties of the tube material were examined at different temperatures and strain rates to determine its flow curves. A parametrical FE model was developed to simulate the bulging process with local heating. Experiments with local heating were executed and metallographic studies of the bulging area were conducted. While specimens heated to 500 °C showed small cracks left, damage-free flanges could be created at 600 and 700 °C. Static testing of damage-free bulges showed improvements in tensile strength and torsion strength compared to bulges formed at room-temperature, while bending and compression behavior remained nearly unchanged. In cyclic testing the locally heated specimens underwent about 3.7 times as many cycles before failure as the specimens formed at room temperature.

  12. Searching for fossil fragments of the Galactic bulge formation process

    Science.gov (United States)

    Ferraro, Francesco

    2017-08-01

    We have discovered that the stellar system Terzan5 (Ter5) in the Galactic bulge harbors stellar populations with very different IRON content (delta[Fe/H] 1 dex, Ferraro+09, Nature 462, 483) and AGES (12 Gyr and 4.5 Gyr for the sub-solar and super-solar metallicity populations, respectively, Ferraro+16, ApJ,828,75). This evidence demonstrates that Ter5 is not a globular cluster, and identifies it as (1) a site in the Galactic bulge where recent star formation occurred, and (2) the remnant of a massive system able to retain the iron-enriched gas ejected by violent supernova explosions. The striking chemical similarity between Ter5 and the bulge opens the fascinating possibility that we discovered the fossil remnant of a pristine massive structure that could have contributed to the Galactic bulge assembly.Prompted by this finding, here we propose to secure deep HST optical observations for the bulge stellar system Liller1, that shows a similar complexity as Ter5, with evidence of two stellar populations with different iron content. The immediate goal is to properly explore the main sequence turnoff region of the system for unveiling possible splits due to stellar populations of different ages. As demonstrated by our experience with Ter5, the requested HST observations, in combination with the K-band diffraction limited images that we already secured with GeMS-Gemini, are essential to achieve this goal.The project will allow us to establish if other fossil remnants of the bulge formation epoch do exist, thus probing that the merging of pre-evolved massive structures has been an important channel for the formation of the Galactic bulge.

  13. Extended thermodynamics

    CERN Document Server

    Müller, Ingo

    1993-01-01

    Physicists firmly believe that the differential equations of nature should be hyperbolic so as to exclude action at a distance; yet the equations of irreversible thermodynamics - those of Navier-Stokes and Fourier - are parabolic. This incompatibility between the expectation of physicists and the classical laws of thermodynamics has prompted the formulation of extended thermodynamics. After describing the motifs and early evolution of this new branch of irreversible thermodynamics, the authors apply the theory to mon-atomic gases, mixtures of gases, relativistic gases, and "gases" of phonons and photons. The discussion brings into perspective the various phenomena called second sound, such as heat propagation, propagation of shear stress and concentration, and the second sound in liquid helium. The formal mathematical structure of extended thermodynamics is exposed and the theory is shown to be fully compatible with the kinetic theory of gases. The study closes with the testing of extended thermodynamics thro...

  14. X-ray Selected Symbiotic Candidates in the Galactic Bulge Survey

    Science.gov (United States)

    Hynes, Robert I.; Wetuski, Joshua` D.; Jonker, Peter; Torres, Manuel; Heinke, Craig O.; Maccarone, Tom; Steeghs, Danny; Britt, Christopher; Johnson, Christopher; Nelemans, Gijs

    2017-06-01

    The Galactic Bulge Survey (GBS) is a broad, shallow survey of Bulge X-ray sources with extensive multiwavelength support. The limiting sensitivity, about 2×1032 erg/s at the Bulge distance, is well suited to finding symbiotic X-ray binaries (SyXBs) containing neutron stars accreting from a cool giant wind, as well as X-ray bright white dwarf systems. Giant counterparts can be securely detected in IR photometry, allowing us to estimate the total number of symbiotics detected by the GBS, and identify a good number of promising candidates. Such an X-ray selected symbiotic sample may be quite different to the traditional symbiotic star population which is usually selected by optical spectroscopy, and consequently biased towards systems with rich line emission. Of the 1640 unique X-ray sources identified by the GBS we find 91 significant matches with candidate Bulge giants. We expect 68 coincidences, so estimate a total sample of about 23 X-ray emitting cool giants detected by the GBS. Most of these are likely to be SyXBs or symbiotics of some type. Narrowing our search to sources coincident to 1", we find 23 matches, with only 8 coincidences expected, so this subsample has a relatively high purity, and likely includes most of the GBS symbiotics. The properties of this subsample are mostly consistent with cool giants, with typical SEDs, long-term lightcurves, and spectra. The sources are inconsistent in color with nearby M dwarfs and show small proper motions, so the foreground contamination is likely small. We present a selection of the best studied objects, focusing on one extremely variable X-ray source coincident with a carbon giant. This is quite an unusual object as carbon stars are rare in the Bulge. The scientific results reported in this article are based on observations made by the Chandra X-ray Observatory and data obtained from the Chandra Data Archive. Support for this work was provided by the National Aeronautics and Space Administration through Chandra

  15. Determination of Material Strengths by Hydraulic Bulge Test

    Directory of Open Access Journals (Sweden)

    Hankui Wang

    2016-12-01

    Full Text Available The hydraulic bulge test (HBT method is proposed to determine material tensile strengths. The basic idea of HBT is similar to the small punch test (SPT, but inspired by the manufacturing process of rupture discs—high-pressure hydraulic oil is used instead of punch to cause specimen deformation. Compared with SPT method, the HBT method can avoid some of influence factors, such as punch dimension, punch material, and the friction between punch and specimen. A calculation procedure that is entirely based on theoretical derivation is proposed for estimate yield strength and ultimate tensile strength. Both conventional tensile tests and hydraulic bulge tests were carried out for several ferrous alloys, and the results showed that hydraulic bulge test results are reliable and accurate.

  16. The 3D Structure of the Galactic Bulge

    Science.gov (United States)

    Zoccali, Manuela; Valenti, Elena

    2016-06-01

    We review the observational evidences concerning the three-dimensional structure of the Galactic bulge. Although the inner few kpc of our Galaxy are normally referred to as the bulge, all the observations demonstrate that this region is dominated by a bar, i.e., the bulge is a bar. The bar has a boxy/peanut (X-shaped) structure in its outer regions, while it seems to become less and less elongated in its innermost region. A thinner and longer structure departing from the main bar has also been found, although the observational evidences that support the scenario of two separate structures has been recently challenged. Metal-poor stars ([Fe/H] ≲ -0.5 dex) trace a different structure, and also have different kinematics.

  17. Bulge-Disk Evolution in Interacting Bulgeless Galaxies

    Science.gov (United States)

    Das, M.; Ramya, S.; Sengupta, C.; Mishra, K.

    2013-10-01

    Bulgeless galaxies are an extreme class of late type spiral galaxies that have practically no bulge and are nearly pure disk in morphology. Their lack of evolution is a puzzle for theories of galaxy formation and the secular evolution of galaxy disks. However, one of the processes by which these galaxies could evolve is through interactions with other galaxies. In this study we present radio (GMRT) observations of star formation in a sample of bulgeless galaxies. We did followup Hα imaging and optical spectroscopy of two galaxies, NGC 3445 and NGC 4027. Both galaxies have extended emission associated with their tidal interactions. Their nuclei show ongoing star formation but no signs of AGN activity. The R band images suggest that their centers have oval distortions or pseudobulges that may later evolve into larger bulges. Thus interactions are an important trigger for the formation of bulges in such disk dominated systems.

  18. Determination of Material Strengths by Hydraulic Bulge Test

    Science.gov (United States)

    Wang, Hankui; Xu, Tong; Shou, Binan

    2016-01-01

    The hydraulic bulge test (HBT) method is proposed to determine material tensile strengths. The basic idea of HBT is similar to the small punch test (SPT), but inspired by the manufacturing process of rupture discs—high-pressure hydraulic oil is used instead of punch to cause specimen deformation. Compared with SPT method, the HBT method can avoid some of influence factors, such as punch dimension, punch material, and the friction between punch and specimen. A calculation procedure that is entirely based on theoretical derivation is proposed for estimate yield strength and ultimate tensile strength. Both conventional tensile tests and hydraulic bulge tests were carried out for several ferrous alloys, and the results showed that hydraulic bulge test results are reliable and accurate. PMID:28772379

  19. Dynamical evolution of a bulge in an N-body model of the Milky Way

    Directory of Open Access Journals (Sweden)

    Gerhard O.

    2012-02-01

    Full Text Available The detailed dynamical structure of the bulge in the Milky Way is currently under debate. Although kinematics of the bulge stars can be well reproduced by a boxy-bulge, the possible existence of a small embedded classical bulge can not be ruled out. We study the dynamical evolution of a small classical bulge in a model of the Milky Way using a self-consistent high resolution N-body simulation. Detailed kinematics and dynamical properties of such a bulge are presented.

  20. General thermodynamics

    CERN Document Server

    Olander, Donald

    2007-01-01

    The book’s methodology is unified, concise, and multidisciplinary, allowing students to understand how the principles of thermodynamics apply to all technical fields that touch upon this most fundamental of scientific theories. It also offers a rigorous approach to the quantitative aspects of thermodynamics, accompanied by clear explanations to help students transition smoothly from the physical concepts to their mathematical representations

  1. Living with a parastomal bulge - patients' experiences of symptoms

    DEFF Research Database (Denmark)

    Krogsgaard, Marianne; Thomsen, Thordis; Vinther, Anders

    2017-01-01

    by the stoma. To cover the physical disfigurement, new clothing solutions, garment wear and creativity were essential in everyday life. Patients gradually adapted to the bulge over time. Easy access to professional help was crucial in order to find the best appliance and garment solution in relation...... is limited and highly warranted to improve clinical outcome. RELEVANCE TO CLINICAL PRACTICE: The ever-changing bulge posed a threat to patients' control of the ostomy and required specific care from the stoma therapist. Needs-based access to counselling, advice and supplementary materials is important....

  2. Disturbance of shaped charge jets by bulging armour

    Energy Technology Data Exchange (ETDEWEB)

    Held, M. [TDW - Gesellschaft fuer Verteidigungstechnische Wirksysteme mbH, Schrobenhausen (Germany)

    2001-10-01

    Two flash X-ray pictures of the passing jet after a bulging armour are presented which give the disturbance effect to the jet - some earlier particulation time and iterative jet eruptions - but only after some time delay. The analysis of the jet velocities of the eruptions allows to calculate the time intervals or roughly the disturbance frequency of the used bulging armour arrangement. In this present paper two tests described with two ''new'' base inert materials - Dyneema - between two metal plates. (orig.)

  3. Galactic Bulges and Inner Disks, as Seen by SAURON

    NARCIS (Netherlands)

    Peletier, R. F.; Ganda, K.; Falcon-Barroso, J.; Bacon, R.; Cappellari, M.; Davies, R. L.; de Zeeuw, P. T.; Emsellem, E.; Krajnovic, D.; Kuntschner, H.; McDermid, R. M.; Sarzi, M.; van de Ven, G.; Funes, JG; Corsini, EM

    2008-01-01

    We discuss SAURON integral field observations of a sample of 42 spirals, ranging in type from Sa to Sd. Using 2D maps of the stellar velocity, velocity dispersion, and absorption line strength, it is now much easier to understand the nature of nearby galactic bulges and inner disks. Here we briefly

  4. An asymmetric mesoscopic model for single bulges in RNA

    Science.gov (United States)

    de Oliveira Martins, Erik; Weber, Gerald

    2017-10-01

    Simple one-dimensional DNA or RNA mesoscopic models are of interest for their computational efficiency while retaining the key elements of the molecular interactions. However, they only deal with perfectly formed DNA or RNA double helices and consider the intra-strand interactions to be the same on both strands. This makes it difficult to describe highly asymmetric structures such as bulges and loops and, for instance, prevents the application of mesoscopic models to determine RNA secondary structures. Here we derived the conditions for the Peyrard-Bishop mesoscopic model to overcome these limitations and applied it to the calculation of single bulges, the smallest and simplest of these asymmetric structures. We found that these theoretical conditions can indeed be applied to any situation where stacking asymmetry needs to be considered. The full set of parameters for group I RNA bulges was determined from experimental melting temperatures using an optimization procedure, and we also calculated average opening profiles for several RNA sequences. We found that guanosine bulges show the strongest perturbation on their neighboring base pairs, considerably reducing the on-site interactions of their neighboring base pairs.

  5. Atmospheric thermodynamics

    CERN Document Server

    Iribarne, J V

    1973-01-01

    The thermodynamics of the atmosphere is the subject of several chapters in most textbooks on dynamic meteorology, but there is no work in English to give the subject a specific and more extensive treatment. In writing the present textbook, we have tried to fill this rather remarkable gap in the literature related to atmospheric sciences. Our aim has been to provide students of meteorology with a book that can playa role similar to the textbooks on chemical thermodynamics for the chemists. This implies a previous knowledge of general thermodynamics, such as students acquire in general physics courses; therefore, although the basic principles are reviewed (in the first four chapters), they are only briefly discussed, and emphasis is laid on those topics that will be useful in later chapters, through their application to atmospheric problems. No attempt has been made to introduce the thermodynamics of irreversible processes; on the other hand, consideration of heterogeneous and open homogeneous systems permits a...

  6. Green thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Cengel, Y.A. [Nevada Univ., Reno, NV (United States). Dept. of Mechanical Engineering

    2006-07-01

    Green components of thermodynamics were identified and general aspects of green practices associated with thermodynamics were assessed. Energy uses associated with fossil fuels were reviewed. Green energy sources such as solar, wind, geothermal and hydropower were discussed, as well as biomass plantations. Ethanol production practices were reviewed. Conservation practices in the United States were outlined. Energy efficiency and exergy analyses were discussed. Energy intensity measurements and insulation products for houses were also reviewed. Five case studies were presented to illustrate aspects of green thermodynamics: (1) light in a classroom; (2) fuel saved by low-resistance tires; and (3) savings with high-efficiency motors; (4) renewable energy; and (5) replacing a valve with a turbine at a cryogenic manufacturing facility. It was concluded that the main principles of green thermodynamics are to ensure that all material and energy inputs minimize the depletion of energy resources; prevent waste; and improve or innovate technologies that achieve sustainability. 17 refs., 2 tabs., 9 figs.

  7. Age bimodality in the central region of pseudo-bulges in S0 galaxies

    Science.gov (United States)

    Mishra, Preetish K.; Barway, Sudhanshu; Wadadekar, Yogesh

    2017-11-01

    We present evidence for bimodal stellar age distribution of pseudo-bulges of S0 galaxies as probed by the Dn(4000) index. We do not observe any bimodality in age distribution for pseudo-bulges in spiral galaxies. Our sample is flux limited and contains 2067 S0 and 2630 spiral galaxies drawn from the Sloan Digital Sky Survey. We identify pseudo-bulges in S0 and spiral galaxies, based on the position of the bulge on the Kormendy diagram and their central velocity dispersion. Dividing the pseudo-bulges of S0 galaxies into those containing old and young stellar populations, we study the connection between global star formation and pseudo-bulge age on the u - r colour-mass diagram. We find that most old pseudo-bulges are hosted by passive galaxies while majority of young bulges are hosted by galaxies that are star forming. Dividing our sample of S0 galaxies into early-type S0s and S0/a galaxies, we find that old pseudo-bulges are mainly hosted by early-type S0 galaxies while most of the pseudo-bulges in S0/a galaxies are young. We speculate that morphology plays a strong role in quenching of star formation in the disc of these S0 galaxies, which stops the growth of pseudo-bulges, giving rise to old pseudo-bulges and the observed age bimodality.

  8. Stochastic thermodynamics

    Science.gov (United States)

    Eichhorn, Ralf; Aurell, Erik

    2014-04-01

    'Stochastic thermodynamics as a conceptual framework combines the stochastic energetics approach introduced a decade ago by Sekimoto [1] with the idea that entropy can consistently be assigned to a single fluctuating trajectory [2]'. This quote, taken from Udo Seifert's [3] 2008 review, nicely summarizes the basic ideas behind stochastic thermodynamics: for small systems, driven by external forces and in contact with a heat bath at a well-defined temperature, stochastic energetics [4] defines the exchanged work and heat along a single fluctuating trajectory and connects them to changes in the internal (system) energy by an energy balance analogous to the first law of thermodynamics. Additionally, providing a consistent definition of trajectory-wise entropy production gives rise to second-law-like relations and forms the basis for a 'stochastic thermodynamics' along individual fluctuating trajectories. In order to construct meaningful concepts of work, heat and entropy production for single trajectories, their definitions are based on the stochastic equations of motion modeling the physical system of interest. Because of this, they are valid even for systems that are prevented from equilibrating with the thermal environment by external driving forces (or other sources of non-equilibrium). In that way, the central notions of equilibrium thermodynamics, such as heat, work and entropy, are consistently extended to the non-equilibrium realm. In the (non-equilibrium) ensemble, the trajectory-wise quantities acquire distributions. General statements derived within stochastic thermodynamics typically refer to properties of these distributions, and are valid in the non-equilibrium regime even beyond the linear response. The extension of statistical mechanics and of exact thermodynamic statements to the non-equilibrium realm has been discussed from the early days of statistical mechanics more than 100 years ago. This debate culminated in the development of linear response

  9. Modern thermodynamics

    CERN Document Server

    Ben-Naim, Arieh

    2017-01-01

    This textbook introduces thermodynamics with a modern approach, starting from four fundamental physical facts (the atomic nature of matter, the indistinguishability of atoms and molecules of the same species, the uncertainty principle, and the existence of equilibrium states) and analyzing the behavior of complex systems with the tools of information theory, in particular with Shannon's measure of information (or SMI), which can be defined on any probability distribution. SMI is defined and its properties and time evolution are illustrated, and it is shown that the entropy is a particular type of SMI, i.e. the SMI related to the phase-space distribution for a macroscopic system at equilibrium. The connection to SMI allows the reader to understand what entropy is and why isolated systems follow the Second Law of Thermodynamics. The Second Llaw is also formulated for other systems, not thermally isolated and even open with respect to the transfer of particles. All the fundamental aspects of thermodynamics are d...

  10. Exponential bulges and antitruncated disks in lenticular galaxies

    OpenAIRE

    Sil'chenko, Olga K.

    2008-01-01

    The presence of exponential bulges and anti-truncated disks has been noticed in many lenticular galaxies. In fact, it could be expected because the very formation of S0 galaxies includes various processes of secular evolution. We discuss how to distinguish between a pseudobulge and an anti-truncated disk, and also what particular mechanisms may be responsible for the formation of anti-truncated disks. Some bright examples of lenticular galaxies with the multi-tiers exponential stellar structu...

  11. Alpha-Bulges in G Protein-Coupled Receptors

    Directory of Open Access Journals (Sweden)

    Rob van der Kant

    2014-05-01

    Full Text Available Agonist binding is related to a series of motions in G protein-coupled receptors (GPCRs that result in the separation of transmembrane helices III and VI at their cytosolic ends and subsequent G protein binding. A large number of smaller motions also seem to be associated with activation. Most helices in GPCRs are highly irregular and often contain kinks, with extensive literature already available about the role of prolines in kink formation and the precise function of these kinks. GPCR transmembrane helices also contain many α-bulges. In this article we aim to draw attention to the role of these α-bulges in ligand and G-protein binding, as well as their role in several aspects of the mobility associated with GPCR activation. This mobility includes regularization and translation of helix III in the extracellular direction, a rotation of the entire helix VI, an inward movement of the helices near the extracellular side, and a concerted motion of the cytosolic ends of the helices that makes their orientation appear more circular and that opens up space for the G protein to bind. In several cases, α-bulges either appear or disappear as part of the activation process.

  12. Solvation thermodynamics

    CERN Document Server

    Ben-Naim, Arieh

    1987-01-01

    This book deals with a subject that has been studied since the beginning of physical chemistry. Despite the thousands of articles and scores of books devoted to solvation thermodynamics, I feel that some fundamen­ tal and well-established concepts underlying the traditional approach to this subject are not satisfactory and need revision. The main reason for this need is that solvation thermodynamics has traditionally been treated in the context of classical (macroscopic) ther­ modynamics alone. However, solvation is inherently a molecular pro­ cess, dependent upon local rather than macroscopic properties of the system. Therefore, the starting point should be based on statistical mechanical methods. For many years it has been believed that certain thermodynamic quantities, such as the standard free energy (or enthalpy or entropy) of solution, may be used as measures of the corresponding functions of solvation of a given solute in a given solvent. I first challenged this notion in a paper published in 1978 b...

  13. Research on aluminum alloy sheet thermoplastic deformation behavior based upon warm bulging test

    Directory of Open Access Journals (Sweden)

    Gaoshen Cai

    2016-02-01

    Full Text Available The rate of fluid pressure variation is a crucial factor to indicate the forming speed and the pressure rate is applied to be one factor that can influence the deformation of material in warm sheet hydroforming. In this study, warm bulging test was conducted to obtain bulging pressure-height curves with different temperatures and pressure rates. Fitting the bulging pressure-equivalent strain curves obtained using bulging test with surface fitting method, the fitted equation of bulging pressure on equivalent strain and pressure rate was achieved, and the fitting result shows a good accordance with experimental and calculated values. Then, the relation between pressure rate and strain rate was obtained. The results of warm bulging test indicated that the deformation behavior of metal material is sensitive to pressure rate, which is of great significance for warm sheet hydroforming.

  14. A combined photometric and kinematic recipe for evaluating the nature of bulges using the CALIFA sample

    Science.gov (United States)

    Neumann, J.; Wisotzki, L.; Choudhury, O. S.; Gadotti, D. A.; Walcher, C. J.; Bland-Hawthorn, J.; García-Benito, R.; González Delgado, R. M.; Husemann, B.; Marino, R. A.; Márquez, I.; Sánchez, S. F.; Ziegler, B.; Califa Collaboration

    2017-07-01

    Understanding the nature of bulges in disc galaxies can provide important insights into the formation and evolution of galaxies. For instance, the presence of a classical bulge suggests a relatively violent history. In contrast, the presence of an inner disc instead (also referred to as a "pseudobulge") indicates the occurrence of secular evolution processes in the main disc. However, we still lack criteria to effectively categorise bulges, limiting our ability to study their impact on the evolution of the host galaxies. Here we present a recipe to separate inner discs from classical bulges by combining four different parameters from photometric and kinematic analyses: the bulge Sérsic index nb, the concentration index C20,50, the Kormendy (1977, ApJ, 217, 406) relation and the inner slope of the radial velocity dispersion profile ∇σ. With that recipe we provide a detailed bulge classification for a sample of 45 galaxies from the integral-field spectroscopic survey CALIFA. To aid in categorising bulges within these galaxies, we perform 2D image decomposition to determine bulge Sérsic index, bulge-to-total light ratio, surface brightness and effective radius of the bulge and use growth curve analysis to derive a new concentration index, C20,50. We further extract the stellar kinematics from CALIFA data cubes and analyse the radial velocity dispersion profile. The results of the different approaches are in good agreement and allow a safe classification for approximately 95% of the galaxies. In particular, we show that our new "inner" concentration index performs considerably better than the traditionally used C50,90 when yielding the nature of bulges. We also found that a combined use of this index and the Kormendy relation gives a very robust indication of the physical nature of the bulge.

  15. Simulations of joule effect heating in a bulge test

    Science.gov (United States)

    Demazel, Nathan; Laurent, Hervé; Carin, Muriel; Coër, Jérémy; Le Masson, Philippe; Favero, Jérôme; Canivenc, Romain; Graveleau, Stéphane

    2016-10-01

    This work focuses on the integration of an electrical conduction heating of circular blank in a bulge test device. This device will be used to characterize the thermomechanical behaviour of Usibor®1500 under biaxial deformation at very high temperature (to 930°C). First a thermoelectric model using COMSOL Multiphysics® was developed to study the heating of a rectangular blank. This model is validated by comparing the calculated temperatures with thermocouples measurements. Secondly electrical field optimization is approached to obtain a fast and uniform heating of a circular blank.

  16. Thermodynamic restrictions on the constitutive equations of electromagnetic theory

    Science.gov (United States)

    Coleman, B. D.; Dill, E. H.

    1971-01-01

    Thermodynamics second law restrictions on constitutive equations of electromagnetic theory for nonlinear materials with long-range gradually fading memory, considering dissipation principle consequences

  17. A Comparison of Galaxy Bulge+Disk Decomposition Between Pan-STARRS and SDSS

    Science.gov (United States)

    Lokken, Martine Elena; McPartland, Conor; Sanders, David B.

    2018-01-01

    Measurements of the size and shape of bulges in galaxies provide key constraints for models of galaxy evolution. A comprehensive catalog of bulge measurements for Sloan Digital Sky Survey (SDSS) DR7 galaxies is currently available to the public. However, the Pan-STARRS1 (PS1) 3π survey now covers the same region with ~1-2 mag deeper photometry, a ~10-30% smaller PSF, and additional coverage in y-band. To test how much improvement in galaxy parameter measurements (e.g. bulge + disk) can be achieved using the new PS1 data, we make use of ultra-deep imaging data from the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP). We fit bulge+disk models to images of 372 bright (mi < 18.5) galaxies detected in all three surveys. Comparison of galaxy parameters derived from SDSS and PS1 images with those measured from HSC-SSP images shows a tighter correlation between PS1 and SSP measurements for both bulge and disk parameters. Bulge parameters, such as bulge-to-total fraction and bulge radius, show the strongest improvement. However, measurements of all parameters degrade for galaxies with total r-band magnitude below the SDSS spectroscopic limit, mr = 17.7. We plan to use the PS1 3π survey data to produce an updated catalog of bulge+disk decomposition measurements for the entire SDSS DR7 spectroscopic galaxy sample.

  18. On the bar formation mechanism in galaxies with cuspy bulges

    Science.gov (United States)

    Polyachenko, E. V.; Berczik, P.; Just, A.

    2016-11-01

    We show by numerical simulations that a purely stellar dynamical model composed of an exponential disc, a cuspy bulge, and a Navarro-Frenk-White halo with parameters relevant to the Milky Way is subject to bar formation. Taking into account the finite disc thickness, the bar formation can be explained by the usual bar instability, in spite of the presence of an inner Lindblad resonance, that is believed to damp any global modes. The effect of replacing the live halo and bulge by a fixed external axisymmetric potential (rigid models) is studied. It is shown that while the e-folding time of bar instability increases significantly (from 250 to 500 Myr), the bar pattern speed remains almost the same. For the latter, our average value of 55 km s-1 kpc-1 agrees with the assumption that the Hercules stream in the solar neighbourhood is an imprint of the bar-disc interaction at the outer Lindblad resonance of the bar. Vertical averaging of the radial force in the central disc region comparable to the characteristic scale length allows us to reproduce the bar pattern speed and the growth rate of the rigid models, using normal mode analysis of linear perturbation theory in a razor-thin disc. The strong increase of the e-folding time with decreasing disc mass predicted by the mode analysis suggests that bars in galaxies similar to the Milky Way have formed only recently.

  19. Observational constraints to boxy/peanut bulge formation time

    Science.gov (United States)

    Pérez, I.; Martínez-Valpuesta, I.; Ruiz-Lara, T.; de Lorenzo-Caceres, A.; Falcón-Barroso, J.; Florido, E.; González Delgado, R. M.; Lyubenova, M.; Marino, R. A.; Sánchez, S. F.; Sánchez-Blázquez, P.; van de Ven, G.; Zurita, A.

    2017-09-01

    Boxy/peanut bulges are considered to be part of the same stellar structure as bars and both could be linked through the buckling instability. The Milky Way is our closest example. The goal of this Letter is to determine if the mass assembly of the different components leaves an imprint in their stellar populations allowing the estimation the time of bar formation and its evolution. To this aim, we use integral field spectroscopy to derive the stellar age distributions, SADs, along the bar and disc of NGC 6032. The analysis clearly shows different SADs for the different bar areas. There is an underlying old (≥12 Gyr) stellar population for the whole galaxy. The bulge shows star formation happening at all times. The inner bar structure shows stars of ages older than 6 Gyr with a deficit of younger populations. The outer bar region presents an SAD similar to that of the disc. To interpret our results, we use a generic numerical simulation of a barred galaxy. Thus, we constrain, for the first time, the epoch of bar formation, the buckling instability period and the posterior growth from disc material. We establish that the bar of NGC 6032 is old, formed around 10 Gyr ago while the buckling phase possibly happened around 8 Gyr ago. All these results point towards bars being long-lasting even in the presence of gas.

  20. Phantom thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)]. E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es; Sigueenza, Carmen L. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)

    2004-10-04

    This paper deals with the thermodynamic properties of a phantom field in a flat Friedmann-Robertson-Walker universe. General expressions for the temperature and entropy of a general dark-energy field with equation of state p={omega}{rho} are derived from which we have deduced that, whereas the temperature of a cosmic phantom fluid ({omega}-1) is definite negative, its entropy is always positive. We interpret that result in terms of the intrinsic quantum nature of the phantom field and apply it to (i) attain a consistent explanation for some recent results concerning the evolution of black holes which,induced by accreting phantom energy, gradually loss their mass to finally vanish exactly at the big rip, and (ii) introduce the concept of cosmological information and its relation with life and the anthropic principle. Some quantum statistical-thermodynamic properties of the quantum field are also considered that include a generalized Wien law and the prediction of some novel phenomena such as the stimulated absorption of phantom energy and the anti-laser effect.

  1. The INTEGRAL Galactic bulge monitoring program: the first 1.5 years

    NARCIS (Netherlands)

    Kuulkers, E.; Shaw, S.E.; Paizis, A.; Chenevez, J.; Brandt, S.; Courvoisier, T.J.L.; Domingo, A.; Ebisawa, K.; Kretschmar, P.; Markwardt, C.B.; Mowlavi, N.; Oosterbroek, T.; Orr, A.; Rísquez, D.; Sanchez-Fernandez, C.; Wijnands, R.

    2007-01-01

    Aims.The Galactic bulge region is a rich host of variable high-energy point sources. Since 2005, February 17 we are monitoring the source activity in the Galactic bulge region regularly and frequently, i.e., about every three days, with the instruments onboard INTEGRAL. Thanks to the large field of

  2. THE SHAPE OF THE LUMINOSITY PROFILES OF BULGES OF SPIRAL GALAXIES

    NARCIS (Netherlands)

    ANDREDAKIS, YC; PELETIER, RF; BALCELLS, M

    1995-01-01

    Using a 2D generalization of Kent's model-independent decomposition method, we extract the K-band light profiles of the bulges of a sample of field galaxies with morphological types ranging from S0 to Sbc. We then examine the shape of the bulge profiles, by means of fitting a seeing-convolved power

  3. Galactic bulges from Hubble Space Telescope NICMOS observations : Global scaling relations

    NARCIS (Netherlands)

    Balcells, Marc; Graham, Alister W.; Peletier, Reynier F.

    2007-01-01

    We investigate bulge and disk scaling relations using a volume-corrected sample of early-to intermediate-type disk galaxies in which, importantly, the biasing flux from additional nuclear components has been modeled and removed. Structural parameters are obtained from a seeing-convolved, bulge +

  4. Equilibrium thermodynamics

    CERN Document Server

    Oliveira, Mário J

    2013-01-01

    This textbook provides an exposition of equilibrium thermodynamics and its applications to several areas of physics with particular attention to phase transitions and critical phenomena. The applications include several areas of condensed matter physics and include also a chapter on thermochemistry. Phase transitions and critical phenomena are treated according to the modern development of the field, based on the ideas of universality and on the Widom scaling theory. For each topic, a mean-field or Landau theory is presented to describe qualitatively the phase transitions.  These theories include the van der Waals theory of the liquid-vapor transition, the Hildebrand-Heitler theory of regular mixtures, the Griffiths-Landau theory for multicritical points in multicomponent systems, the Bragg-Williams theory of order-disorder in alloys, the Weiss theory of ferromagnetism, the Néel theory of antiferromagnetism, the Devonshire theory for ferroelectrics and Landau-de Gennes theory of liquid crystals. This textbo...

  5. Equilibrium thermodynamics

    CERN Document Server

    de Oliveira, Mário J

    2017-01-01

    This textbook provides an exposition of equilibrium thermodynamics and its applications to several areas of physics with particular attention to phase transitions and critical phenomena. The applications include several areas of condensed matter physics and include also a chapter on thermochemistry. Phase transitions and critical phenomena are treated according to the modern development of the field, based on the ideas of universality and on the Widom scaling theory. For each topic, a mean-field or Landau theory is presented to describe qualitatively the phase transitions. These theories include the van der Waals theory of the liquid-vapor transition, the Hildebrand-Heitler theory of regular mixtures, the Griffiths-Landau theory for multicritical points in multicomponent systems, the Bragg-Williams theory of order-disorder in alloys, the Weiss theory of ferromagnetism, the Néel theory of antiferromagnetism, the Devonshire theory for ferroelectrics and Landau-de Gennes theory of liquid crystals. This new edit...

  6. Latitudinal plasma distribution in the dusk plasmaspheric bulge - Refilling phase and quasi-equilibrium state

    Science.gov (United States)

    Decreau, P. M. E.; Carpenter, D.; Chappell, C. R.; Green, J.; Waite, J. H., Jr.

    1986-01-01

    Very low-energy trapped ions, mostly protons, have been observed in a region of moderate density characteristic of the plasmapause boundary and of the plasmaspheric bulge. The present paper is concerned with an examination of the latitudinal structure of the bulge under quasi-steady conditions and the conditions of the recovery phase. Details regarding the data base are considered along with observations of the morphology and dynamics of the bulge, the latitudinal density distribution in the expanded bulge, the convection scenario during the replenishment phase, and latitudinal effects on plasma characteristics during plasmasphere refilling. The data utilized have been mainly provided by the DE 1 and GEOS 2 spacecraft traveling in two perpendicular planes. It is found that the bulge is a dynamic region, where no reasonable interpretation of the observed density distribution can be achieved without taking into account the mechanism of magnetospheric convection.

  7. VizieR Online Data Catalog: Box- and peanut-shaped bulges. I. (Luetticke+, 2000)

    Science.gov (United States)

    Luetticke, R.; Dettmar, R.-J.; Pohlen, M.

    2000-08-01

    BUTY presents in its main part (table 6) a classification for bulges of a complete sample of 1224 edge-on disk galaxies (D25>2arcmin, logR25>0.35 for S0/a-Sd galaxies and log R25>0.30 for S0 galaxies) derived from the RC3 (Third Reference Catalogue of Bright Galaxies, de Vaucouleurs et al., 1991, Cat. ). Using the Digitized Sky Survey (DSS), the bulge shape is visually classified in three types of box- and peanut-shaped (b/p) bulges or as an elliptical type. The extension of BUTY (table 7) contains the classification of bulges of additional 83 galaxies, which do not fulfill the selection criterion of our RC3 sample. They are observed with CCD images (optical or NIR) or are investigated in previous studies about b/p bulges. (3 data files).

  8. The Composition of the Bulge Globular Cluster NGC 6273

    Science.gov (United States)

    Pilachowski, C. A.; Johnson, C. I.; Rich, R. M.; Caldwell, N.; Mateo, M.; Bailey, J. I.; Crane, J. D.

    2017-03-01

    Observations of red giants in the Bulge globular cluster NGC 6273 with the Michigan/Magellan Fiber System (M2FS) mounted on the Nasmuth-East port of the Magellan-Clay 6.5-m telescope at the Las Campanas Observatory reveal a spread in metallicity. Members have been confirmed with radial velocity. NGC 6273 has at least two populations separated by 0.2-0.3 dex in [Fe/H]. The sodium and aluminum abundances are correlated while the magnesium and aluminum abundances are anti-correlated. The cluster also shows a rise in the abundance of the s-process element lanthanum with [Fe/H] similar to other massive clusters. The cluster contains a possible third population depleted in most elements by 0.3 dex.

  9. A TWO-PHASE SCENARIO FOR BULGE ASSEMBLY IN {Lambda}CDM COSMOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Obreja, A.; Dominguez-Tenreiro, R.; Brook, C. [Departamento de Fisica Teorica, Universidad Autonoma de Madrid, E-28049 Cantoblanco Madrid (Spain); Martinez-Serrano, F. J.; Domenech-Moral, M.; Serna, A. [Departamento de Fisica y Arquitectura de Computadores, Universidad Miguel Hernandez, E-03202 Elche (Spain); Molla, M. [Departamento de Investigacion Basica, CIEMAT, E-28040 Madrid (Spain); Stinson, G., E-mail: aura.obreja@uam.es [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117, Heidelberg (Germany)

    2013-01-20

    We analyze and compare the bulges of a sample of L {sub *} spiral galaxies in hydrodynamical simulations in a cosmological context, using two different codes, P-DEVA and GASOLINE. The codes regulate star formation in very different ways, with P-DEVA simulations inputting low star formation efficiency under the assumption that feedback occurs on subgrid scales, while the GASOLINE simulations have feedback that drives large-scale outflows. In all cases, the marked knee shape in mass aggregation tracks, corresponding to the transition from an early phase of rapid mass assembly to a later slower one, separates the properties of two populations within the simulated bulges. The bulges analyzed show an important early starburst resulting from the collapse-like fast phase of mass assembly, followed by a second phase with lower star formation, driven by a variety of processes such as disk instabilities and/or mergers. Classifying bulge stellar particles identified at z = 0 into old and young according to these two phases, we found bulge stellar sub-populations with distinct kinematics, shapes, stellar ages, and metal contents. The young components are more oblate, generally smaller, more rotationally supported, with higher metallicity and less alpha-element enhanced than the old ones. These results are consistent with the current observational status of bulges, and provide an explanation for some apparently paradoxical observations, such as bulge rejuvenation and metal-content gradients observed. Our results suggest that bulges of L {sub *} galaxies will generically have two bulge populations that can be likened to classical and pseudo-bulges, with differences being in the relative proportions of the two, which may vary due to galaxy mass and specific mass accretion and merger histories.

  10. Thermodynamics of Radiation Modes

    Science.gov (United States)

    Pina, Eduardo; de la Selva, Sara Maria Teresa

    2010-01-01

    We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the…

  11. Thermodynamics of Benford's First Digit Law

    CERN Document Server

    Lemons, Don S

    2016-01-01

    Iafrate, Miller, and Strauch [Equipartition and a Distribution for Numbers: A Statistical Model for Benford's Law," arXiv:1503.08259] construct and test a statistical model for partitioning a conserved quantity. One consequence of their model is Benford's law. This Comment amplifies their work by exploring its thermodynamic consequences.

  12. Bulge testing of copper and niobium tubes for hydroformed RF cavities

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H.S., E-mail: kim.3237@osu.edu [Department of Materials Science and Engineering, The Ohio State University, Columbus, OH (United States); Sumption, M.D. [Department of Materials Science and Engineering, The Ohio State University, Columbus, OH (United States); Susner, M.A. [Department of Materials Science and Engineering, The Ohio State University, Columbus, OH (United States); Oak Ridge National Laboratory, Oak Ridge, TN (United States); Lim, H. [Department of Materials Science and Engineering, The Ohio State University, Columbus, OH (United States); Sandia National Laboratories, Albuquerque, NM (United States); Collings, E.W. [Department of Materials Science and Engineering, The Ohio State University, Columbus, OH (United States)

    2016-01-27

    The heat treatment, tensile testing, and bulge testing of Cu and Nb tubes has been carried out to gain experience for the subsequent hydroforming of Nb tube into seamless superconducting radio frequency (SRF) cavities for high energy particle acceleration. In the experimental part of the study samples removed from representative tubes were prepared for heat treatment, tensile testing, residual resistance ratio measurement, and orientation imaging electron microscopy (OIM). After being optimally heat treated Cu and Nb tubes were subjected to hydraulic bulge testing and the results analyzed. In the final part of the study finite-element models (FEM) incorporating constitutive (stress–strain) relationships analytically derived from the tensile and bulge tests, respectively, were used to replicate the bulge test. As expected, agreement was obtained between the experimental bulge parameters and the FEM model based on the bulge-derived constitutive relationship. Not so for the FEM model based on tensile-test data. It is concluded that a constitutive relationship based on bulge testing is necessary to predict a material's performance under hydraulic deformation.

  13. Bulging Behavior of Thin-walled Welded Low Carbon Steel Tubes

    Directory of Open Access Journals (Sweden)

    XIE Wen-cai

    2017-01-01

    Full Text Available In order to investigate the deformation behaviour of welded tubes during hydraulic bulging process,the hydraulic bulging tests of thin-walled welded low carbon steel tubes (STKM11A were conducted on the tube hydroformability testing unit.The thickness distribution,profiles of bulging area and the strain distribution were all obtained.Results show that the thickness reduction of weld zone is just 2.4%-5.5% while its effective strain is just 0.05-0.10,which is very small and negligible compared with the parent material and means that just the geometric position of weld zone is changed with the continuous bulging.The thinnest points are located on the both sides of weld seam symmetrically and the angle between the thinnest point and weld seam is about 30°,at which the necking has been occurred.When the length of bulging area increases,the fracture pressure,the thickness reduction and the ultimate expansion ratio all decrease,and the profile of the bulging area gradually steps away from the elliptical model which is powerless for the ratio of length to diameter up to 2.0.Moreover,the strain state of the tube is transformed from biaxial tension to plane strain state with the increasing length of bulging area,on the basis of this the forming limit diagram of welded STKM11A steel tubes can be established.

  14. Factors associated with hernia and bulge formation at the donor site of the pedicled TRAM flap.

    Science.gov (United States)

    Rossetto, Luis Antonio; Abla, Luiz Eduardo Felipe; Vidal, Ronaldo; Garcia, Elvio Bueno; Gonzalez, Ricardo João; Gebrim, Luiz Henrique; Neto, Miguel Sabino; Ferreira, Lydia Masako

    2010-08-01

    The purpose of this study was to evaluate the correlation between risk factors and hernia or bulge formation at the donor site of the transverse rectus abdominis myocutaneous (TRAM) flap. A retrospective study was conducted between September 2005 and December 2008 in 206 patients who underwent breast reconstruction with pedicled TRAM flap. Eight (3.9%) of these patients had abdominal wall hernia and 26 (12.6%) had abdominal bulging. The incidence of hernia was significantly higher (P /= 30 kg/m(2) (hernia incidence, 15.0%) than that among patients with BMI /= 30 kg/m(2) (abdominal bulge incidence, 5.0%) than that among patients with BMI >/= 30 kg/m(2) (abdominal bulge incidence, 19.1%). Therefore, obesity was identified as a risk factor for abdominal wall hernia. It was also found that the use of mesh to reinforce the abdominal wall significantly reduced (P < 0.025) the incidence of hernia (use of mesh (hernia incidence, 2.5%) versus non-mesh (hernia incidence, 5.9%)) and abdominal bulge (use of mesh (abdominal bulge incidence, 9.9%) versus non-mesh (abdominal bulge incidence, 17.3%)) among the patients.

  15. Effect of an upstream bulge configuration on film cooling with and without mist injection.

    Science.gov (United States)

    Wang, Jin; Li, Qianqian; Sundén, Bengt; Ma, Ting; Cui, Pei

    2017-12-01

    To meet the economic requirements of power output, the increased inlet temperature of modern gas turbines is above the melting point of the material. Therefore, high-efficient cooling technology is needed to protect the blades from the hot mainstream. In this study, film cooling was investigated in a simplified channel. A bulge located upstream of the film hole was numerically investigated by analysis of the film cooling effectiveness distribution downstream of the wall. The flow distribution in the plate channel is first presented. Comparing with a case without bulge, different cases with bulge heights of 0.1d, 0.3d and 0.5d were examined with blowing ratios of 0.5 and 1.0. Cases with 1% mist injection were also included in order to obtain better cooling performance. Results show that the bulge configuration located upstream the film hole makes the cooling film more uniform, and enhanceslateral cooling effectiveness. Unlike other cases, the configuration with a 0.3d-height bulge shows a good balance in improving the downstream and lateral cooling effectiveness. Compared with the case without mist at M = 0.5, the 0.3d-height bulge with 1% mist injection increases lateral average effectiveness by 559% at x/d = 55. In addition, a reduction of the thermal stress concentration can be obtained by increasing the height of the bulge configuration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Comparative Analysis of Bulge Deformation between 2D and 3D Finite Element Models

    Directory of Open Access Journals (Sweden)

    Qin Qin

    2014-02-01

    Full Text Available Bulge deformation of the slab is one of the main factors that affect slab quality in continuous casting. This paper describes an investigation into bulge deformation using ABAQUS to model the solidification process. A three-dimensional finite element analysis model of the slab solidification process has been first established because the bulge deformation is closely related to slab temperature distributions. Based on slab temperature distributions, a three-dimensional thermomechanical coupling model including the slab, the rollers, and the dynamic contact between them has also been constructed and applied to a case study. The thermomechanical coupling model produces outputs such as the rules of bulge deformation. Moreover, the three-dimensional model has been compared with a two-dimensional model to discuss the differences between the two models in calculating the bulge deformation. The results show that the platform zone exists in the wide side of the slab and the bulge deformation is affected strongly by the ratio of width-to-thickness. The indications are also that the difference of the bulge deformation for the two modeling ways is little when the ratio of width-to-thickness is larger than six.

  17. Stellar populations of bulges in galaxies with a low surface-brightness disc

    Science.gov (United States)

    Morelli, L.; Corsini, E. M.; Pizzella, A.; Dalla Bontà, E.; Coccato, L.; Méndez-Abreu, J.

    2015-03-01

    The radial profiles of the Hβ, Mg, and Fe line-strength indices are presented for a sample of eight spiral galaxies with a low surface-brightness stellar disc and a bulge. The correlations between the central values of the line-strength indices and velocity dispersion are consistent to those known for early-type galaxies and bulges of high surface-brightness galaxies. The age, metallicity, and α/Fe enhancement of the stellar populations in the bulge-dominated region are obtained using stellar population models with variable element abundance ratios. Almost all the sample bulges are characterized by a young stellar population, on-going star formation, and a solar α/Fe enhancement. Their metallicity spans from high to sub-solar values. No significant gradient in age and α/Fe enhancement is measured, whereas only in a few cases a negative metallicity gradient is found. These properties suggest that a pure dissipative collapse is not able to explain formation of all the sample bulges and that other phenomena, like mergers or acquisition events, need to be invoked. Such a picture is also supported by the lack of a correlation between the central value and gradient of the metallicity in bulges with very low metallicity. The stellar populations of the bulges hosted by low surface-brightness discs share many properties with those of high surface-brightness galaxies. Therefore, they are likely to have common formation scenarios and evolution histories. A strong interplay between bulges and discs is ruled out by the fact that in spite of being hosted by discs with extremely different properties, the bulges of low and high surface-brightness discs are remarkably similar.

  18. Morpho-kinematic properties of field S0 bulges in the CALIFA survey

    Science.gov (United States)

    Méndez-Abreu, J.; Aguerri, J. A. L.; Falcón-Barroso, J.; Ruiz-Lara, T.; Sánchez-Menguiano, L.; de Lorenzo-Cáceres, A.; Costantin, L.; Catalán-Torrecilla, C.; Zhu, L.; Sánchez-Blazquez, P.; Florido, E.; Corsini, E. M.; Wild, V.; Lyubenova, M.; van de Ven, G.; Sánchez, S. F.; Bland-Hawthorn, J.; Galbany, L.; García-Benito, R.; García-Lorenzo, B.; González Delgado, R. M.; López-Sánchez, A. R.; Marino, R. A.; Márquez, I.; Ziegler, B.; Califa Collaboration

    2018-02-01

    We study a sample of 28 S0 galaxies extracted from the integral field spectroscopic (IFS) survey Calar Alto Legacy Integral Field Area. We combine an accurate two-dimensional (2D) multicomponent photometric decomposition with the IFS kinematic properties of their bulges to understand their formation scenario. Our final sample is representative of S0s with high stellar masses (M⋆/M⊙ > 1010). They lay mainly on the red sequence and live in relatively isolated environments similar to that of the field and loose groups. We use our 2D photometric decomposition to define the size and photometric properties of the bulges, as well as their location within the galaxies. We perform mock spectroscopic simulations mimicking our observed galaxies to quantify the impact of the underlying disc on our bulge kinematic measurements (λ and v/σ). We compare our bulge corrected kinematic measurements with the results from Schwarzschild dynamical modelling. The good agreement confirms the robustness of our results and allows us to use bulge deprojected values of λ and v/σ. We find that the photometric (n and B/T) and kinematic (v/σ and λ) properties of our field S0 bulges are not correlated. We demonstrate that this morpho-kinematic decoupling is intrinsic to the bulges and it is not due to projection effects. We conclude that photometric diagnostics to separate different types of bulges (disc-like versus classical) might not be useful for S0 galaxies. The morpho-kinematics properties of S0 bulges derived in this paper suggest that they are mainly formed by dissipational processes happening at high redshift, but dedicated high-resolution simulations are necessary to better identify their origin.

  19. Mathematical foundations of thermodynamics

    CERN Document Server

    Giles, R; Stark, M; Ulam, S

    2013-01-01

    Mathematical Foundations of Thermodynamics details the core concepts of the mathematical principles employed in thermodynamics. The book discusses the topics in a way that physical meanings are assigned to the theoretical terms. The coverage of the text includes the mechanical systems and adiabatic processes; topological considerations; and equilibrium states and potentials. The book also covers Galilean thermodynamics; symmetry in thermodynamics; and special relativistic thermodynamics. The book will be of great interest to practitioners and researchers of disciplines that deal with thermodyn

  20. Hadron thermodynamics in relativistic nuclear collisions

    Science.gov (United States)

    Ammiraju, P.

    1985-01-01

    Various phenomenological models based on statistical thermodynamical considerations were used to fit the experimental data at high P sub T to a two temperature distribution. Whether this implies that the two temperatures belong to two different reaction mechanisms, or consequences of Lorentz-contraction factor, or related in a fundamental way to the intrinsic thermodynamics of Space-Time can only be revealed by further theoretical and experimental investigations of high P sub T phenomena in extremely energetic hadron-hadron collisions.

  1. Thermodynamic tables to accompany Modern engineering thermodynamics

    CERN Document Server

    Balmer, Robert T

    2011-01-01

    This booklet is provided at no extra charge with new copies of Balmer's Modern Engineering Thermodynamics. It contains two appendices. Appendix C contains 40 thermodynamic tables, and Appendix D consists of 6 thermodynamic charts. These charts and tables are provided in a separate booklet to give instructors the flexibility of allowing students to bring the tables into exams. The booklet may be purchased separately if needed.

  2. Classical and statistical thermodynamics

    CERN Document Server

    Rizk, Hanna A

    2016-01-01

    This is a text book of thermodynamics for the student who seeks thorough training in science or engineering. Systematic and thorough treatment of the fundamental principles rather than presenting the large mass of facts has been stressed. The book includes some of the historical and humanistic background of thermodynamics, but without affecting the continuity of the analytical treatment. For a clearer and more profound understanding of thermodynamics this book is highly recommended. In this respect, the author believes that a sound grounding in classical thermodynamics is an essential prerequisite for the understanding of statistical thermodynamics. Such a book comprising the two wide branches of thermodynamics is in fact unprecedented. Being a written work dealing systematically with the two main branches of thermodynamics, namely classical thermodynamics and statistical thermodynamics, together with some important indexes under only one cover, this treatise is so eminently useful.

  3. VARIABILITY OF OPTICAL COUNTERPARTS IN THE CHANDRA GALACTIC BULGE SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Britt, C. T.; Hynes, R. I.; Johnson, C. B.; Baldwin, A.; Collazzi, A.; Gossen, L. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001 (United States); Jonker, P. G.; Torres, M. A. P. [SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands); Nelemans, G. [Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ, Nijmegen (Netherlands); Maccarone, T. [Department of Physics, Texas Tech University, Box 41051, Science Building, Lubbock, TX 79409-1051 (United States); Steeghs, D.; Greiss, S. [Astronomy and Astrophysics, Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Heinke, C. [Department of Physics, University of Alberta, CCIS 4-183, Edmonton, AB T6G 2E1 (Canada); Bassa, C. G. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Villar, A. [Department of Physics, Massachussettes Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 (United States); Gabb, M. [Department of Physics, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431-0991 (United States)

    2014-09-01

    We present optical light curves of variable stars consistent with the positions of X-ray sources identified with the Chandra X-ray Observatory for the Chandra Galactic Bulge Survey (GBS). Using data from the Mosaic-II instrument on the Blanco 4 m Telescope at CTIO, we gathered time-resolved photometric data on timescales from ∼2 hr to 8 days over the 3/4 of the X-ray survey containing sources from the initial GBS catalog. Among the light curve morphologies we identify are flickering in interacting binaries, eclipsing sources, dwarf nova outbursts, ellipsoidal variations, long period variables, spotted stars, and flare stars. Eighty-seven percent of X-ray sources have at least one potential optical counterpart. Twenty-seven percent of these candidate counterparts are detectably variable; a much greater fraction than expected for randomly selected field stars, which suggests that most of these variables are real counterparts. We discuss individual sources of interest, provide variability information on candidate counterparts, and discuss the characteristics of the variable population.

  4. The Bulge Metallicity Distribution from the APOGEE Survey

    Science.gov (United States)

    García Pérez, Ana E.; Ness, Melissa; Robin, Annie C.; Martinez-Valpuesta, Inma; Sobeck, Jennifer; Zasowski, Gail; Majewski, Steven R.; Bovy, Jo; Allende Prieto, Carlos; Cunha, Katia; Girardi, Léo; Mészáros, Szabolcs; Nidever, David; Schiavon, Ricardo P.; Schultheis, Mathias; Shetrone, Matthew; Smith, Verne V.

    2018-01-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) provides spectroscopic information of regions of the inner Milky Way, which are inaccessible to optical surveys. We present the first large study of the metallicity distribution of the innermost Galactic regions based on high-quality measurements for 7545 red giant stars within 4.5 kpc of the Galactic center, with the goal to shed light on the structure and origin of the Galactic bulge. Stellar metallicities are found, through multiple Gaussian decompositions, to be distributed in several components, which is indicative of the presence of various stellar populations such as the bar or the thin and the thick disks. Super-solar ([Fe/H] = +0.32) and solar ([Fe/H] = +0.00) metallicity components, tentatively associated with the thin disk and the Galactic bar, respectively, seem to be major contributors near the midplane. A solar-metallicity component extends outwards in the midplane but is not observed in the innermost regions. The central regions (within 3 kpc of the Galactic center) reveal, on the other hand, the presence of a significant metal-poor population ([Fe/H] = ‑0.46), tentatively associated with the thick disk, which becomes the dominant component far from the midplane (| Z| ≥slant +0.75 kpc). Varying contributions from these different components produce a transition region at +0.5 kpc ≤slant | Z| ≤slant +1.0 {kpc}, characterized by a significant vertical metallicity gradient.

  5. APOGEE Kinematics. I. Overview of the Kinematics of the Galactic Bulge as Mapped By APOGEE

    Science.gov (United States)

    Ness, M.; Zasowski, G.; Johnson, J. A.; Athanassoula, E.; Majewski, S. R.; García Pérez, A. E.; Bird, J.; Nidever, D.; Schneider, Donald P.; Sobeck, J.; Frinchaboy, P.; Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey

    2016-03-01

    We present the stellar kinematics across the Galactic bulge and into the disk at positive longitudes from the SDSS-III APOGEE spectroscopic survey of the Milky Way. APOGEE includes extensive coverage of the stellar populations of the bulge along the midplane and near-plane regions. From these data, we have produced kinematic maps of 10,000 stars across longitudes of 0° dispersion maps of barred galaxies viewed edge-on. The thin bar that is reported to be present in the inner disk within a narrow latitude range of | b| -0.5 have dispersion and rotation profiles that are similar to that of N-body models of boxy/peanut bulges. There is a smooth kinematic transition from the thin bar and boxy bulge (l,| b| ) -1.0, and the chemodynamics across (l, b) suggests that the stars in the inner Galaxy with [{Fe}/{{H}}] > -1.0 originate in the disk.

  6. Iran’s Youth Bulge and It’s Implications for U.S. National Security

    Science.gov (United States)

    2006-04-01

    instability is unemployment . Since youths are historically more likely to be unemployed than older generations, youth bulges exacerbate the problem...the rest of the region shares similar if not worse youth unemployment problems. 10 Thus, “…most theoretical works concerned with youth bulges...Bank’s Kabbani, is “Empirical evidence suggests that macroeconomic conditions are more important determinants of both youth and adult unemployment rates

  7. A Catalog of Edge-on Disk Galaxies: From Galaxies with a Bulge to Superthin Galaxies

    OpenAIRE

    Kautsch, S. J.; Grebel, E. K.; Barazza, F. D.; Gallagher, J. S.

    2005-01-01

    The formation and evolution of disk-dominated galaxies is difficult to explain, yet these objects exist. We therefore embarked on a study aimed at a better understanding of these enigmatic objects. We used data from the SDSS DR1 in order to identify edge-on galaxies with disks in a uniform, reproducible, automated fashion. We identified 3169 edge-on disk galaxies, which we subdivided into disk galaxies with bulge, intermediate types, and simple disk galaxies without any obvious bulge componen...

  8. Model for coeval growth of bulges and their seed black holes in presence of radiative feedback

    Science.gov (United States)

    Park, KwangHo; Bogdanovic, Tamara; Wise, John

    2017-01-01

    The discovery of billion solar mass accreting black holes at high redshift poses a great challenge for the modeling of the seed black hole (BH) formation and growth. Radiation-hydrodynamic simulations represent a crucial test of plausible scenarios by providing estimated growth rates for the seeds in the intermediate-mass black hole range. Previous works show that radiative feedback from black holes suppresses the cold gas accretion rate dramatically, making it difficult to explain the rapid growth of seed black holes. We however find that the fueling rate of black holes embedded in bulges can increase with the bulge-to-BH mass ratio when the bulge mass is greater than the critical value of ˜106 M⊙. The critical bulge mass is independent of the central black hole mass, thus the growth rate of light seeds ( 105 M⊙) exhibits distinct dependencies on the bulge-to-BH mass ratio. Our results imply that heavy seeds, that may form via direct collapse, can grow efficiently and coevally with the host galaxies despite radiative feedback whereas the growth of light seeds is stunted. We present the results of an extended semi-analytic model based on the radiation-hydrodynamic simulations, which follows the coeval growth of black holes and their bulges.

  9. A HIGH-VELOCITY BULGE RR LYRAE VARIABLE ON A HALO-LIKE ORBIT

    Energy Technology Data Exchange (ETDEWEB)

    Kunder, Andrea; Storm, J. [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Rich, R. M. [Department of Physics and Astronomy, University of California at Los Angeles, Los Angeles, CA 90095-1562 (United States); Hawkins, K. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Poleski, R. [Department of Astronomy, Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210 (United States); Johnson, C. I. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Shen, J.; Li, Z.-Y. [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China); Cordero, M. J. [Astronomisches Rechen-Institut: Zentrum für Astronomie, Mönchhofstr. 12-14, D-69120 Heidelberg (Germany); Nataf, D. M. [Research School of Astronomy and Astrophysics, The Australian National University, Canberra, ACT 2611 (Australia); Bono, G. [Dipartimento di Fisica, Universita di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Roma (Italy); Walker, A. R. [Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile); Koch, A. [Landessternwarte, Zentrum für Astronomie der Universität Heidelberg, Königstuhl 12, D-69117 Heidelberg (Germany); De Propris, R. [Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Turku (Finland); Udalski, A.; Szymanski, M. K.; Soszynski, I.; Pietrzynski, G.; Ulaczyk, K.; Wyrzykowski, Ł. [Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa (Poland); and others

    2015-07-20

    We report on the RR Lyrae variable star, MACHO 176.18833.411, located toward the Galactic bulge and observed within the data from the ongoing Bulge RR Lyrae Radial Velocity Assay, which has the unusual radial velocity of −372 ± 8 km s{sup −1} and true space velocity of −482 ± 22 km s{sup −1} relative to the Galactic rest frame. Located less than 1 kpc from the Galactic center and toward a field at (l, b) = (3, −2.5), this pulsating star has properties suggesting it belongs to the bulge RR Lyrae star population, yet a velocity indicating it is abnormal, at least with respect to bulge giants and red clump stars. We show that this star is most likely a halo interloper and therefore suggest that halo contamination is not insignificant when studying metal-poor stars found within the bulge area, even for stars within 1 kpc of the Galactic center. We discuss the possibility that MACHO 176.18833.411 is on the extreme edge of the bulge RR Lyrae radial velocity distribution, and also consider a more exotic scenario in which it is a runaway star moving through the Galaxy.

  10. Gauging the Helium Abundance of the Galactic Bulge RR Lyrae Stars

    Science.gov (United States)

    Marconi, Marcella; Minniti, Dante

    2018-02-01

    We report the first estimate of the He abundance of the population of RR Lyrae stars in the Galactic bulge. This is done by comparing the recent observational data with the latest models. We use the large samples of ab-type RR Lyrae stars found by OGLE IV in the inner bulge and by the VVV survey in the outer bulge. We present the result from the new models computed by Marconi et al., showing that the minimum period for fundamental RR Lyrae pulsators depends on the He content. By comparing these models with the observations in a period versus effective temperature plane, we find that the bulk of the bulge ab-type RR Lyrae are consistent with primordial He abundance Y = 0.245, ruling out a significant He-enriched population. This work demonstrates that the He content of the bulge RR Lyrae is different from that of the bulk of the bulge population as traced by the red clump giants that appear to be significantly more He-rich. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 179.B-2002 and 298.D-5048.

  11. Conformal Gauge Transformations in Thermodynamics

    Directory of Open Access Journals (Sweden)

    Alessandro Bravetti

    2015-09-01

    Full Text Available In this work, we show that the thermodynamic phase space is naturally endowed with a non-integrable connection, defined by all of those processes that annihilate the Gibbs one-form, i.e., reversible processes. We argue that such a connection is invariant under re-scalings of the connection one-form, whilst, as a consequence of the non-integrability of the connection, its curvature is not and, therefore, neither is the associated pseudo-Riemannian geometry. We claim that this is not surprising, since these two objects are associated with irreversible processes. Moreover, we provide the explicit form in which all of the elements of the geometric structure of the thermodynamic phase space change under a re-scaling of the connection one-form. We call this transformation of the geometric structure a conformal gauge transformation. As an example, we revisit the change of the thermodynamic representation and consider the resulting change between the two metrics on the thermodynamic phase space, which induce Weinhold’s energy metric and Ruppeiner’s entropy metric. As a by-product, we obtain a proof of the well-known conformal relation between Weinhold’s and Ruppeiner’s metrics along the equilibrium directions. Finally, we find interesting properties of the almost para-contact structure and of its eigenvectors, which may be of physical interest.

  12. Treatise on thermodynamics

    CERN Document Server

    Planck, Max Karl Ernst Ludwig

    Great classic, still one of the best introductions to thermodynamics. Fundamentals, first and second principles of thermodynamics, applications to special states of equilibrium, more. Numerous worked examples. 1917 edition.

  13. The Gaia-ESO Survey: Exploring the complex nature and origins of the Galactic bulge populations

    Science.gov (United States)

    Rojas-Arriagada, A.; Recio-Blanco, A.; de Laverny, P.; Mikolaitis, Š.; Matteucci, F.; Spitoni, E.; Schultheis, M.; Hayden, M.; Hill, V.; Zoccali, M.; Minniti, D.; Gonzalez, O. A.; Gilmore, G.; Randich, S.; Feltzing, S.; Alfaro, E. J.; Babusiaux, C.; Bensby, T.; Bragaglia, A.; Flaccomio, E.; Koposov, S. E.; Pancino, E.; Bayo, A.; Carraro, G.; Casey, A. R.; Costado, M. T.; Damiani, F.; Donati, P.; Franciosini, E.; Hourihane, A.; Jofré, P.; Lardo, C.; Lewis, J.; Lind, K.; Magrini, L.; Morbidelli, L.; Sacco, G. G.; Worley, C. C.; Zaggia, S.

    2017-05-01

    Context. As observational evidence steadily accumulates, the nature of the Galactic bulge has proven to be rather complex: the structural, kinematic, and chemical analyses often lead to contradictory conclusions. The nature of the metal-rich bulge - and especially of the metal-poor bulge - and their relation with other Galactic components, still need to be firmly defined on the basis of statistically significant high-quality data samples. Aims: We used the fourth internal data release of the Gaia-ESO survey to characterize the bulge metallicity distribution function (MDF), magnesium abundance, spatial distribution, and correlation of these properties with kinematics. Moreover, the homogeneous sampling of the different Galactic populations provided by the Gaia-ESO survey allowed us to perform a comparison between the bulge, thin disk, and thick disk sequences in the [Mg/Fe] vs. [Fe/H] plane in order to constrain the extent of their eventual chemical similarities. Methods: We obtained spectroscopic data for 2500 red clump stars in 11 bulge fields, sampling the area -10° ≤ l ≤ + 8° and -10° ≤ b ≤ -4° from the fourth internal data release of the Gaia-ESO survey. A sample of 6300 disk stars was also selected for comparison. Spectrophotometric distances computed via isochrone fitting allowed us to define a sample of stars likely located in the bulge region. Results: From a Gaussian mixture models (GMM) analysis, the bulge MDF is confirmed to be bimodal across the whole sampled area. The relative ratio between the two modes of the MDF changes as a function of b, with metal-poor stars dominating at high latitudes. The metal-rich stars exhibit bar-like kinematics and display a bimodality in their magnitude distribution, a feature which is tightly associated with the X-shape bulge. They overlap with the metal-rich end of the thin disk sequence in the [Mg/Fe] vs. [Fe/H] plane. On the other hand, metal-poor bulge stars have a more isotropic hot kinematics and do

  14. Supermassive black holes and their host galaxies. I. Bulge luminosities from dedicated near-infrared data

    Energy Technology Data Exchange (ETDEWEB)

    Läsker, Ronald; Van de Ven, Glenn [Max-Planck Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Ferrarese, Laura, E-mail: laesker@mpia.de [NRC Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E2E7 (Canada)

    2014-01-01

    In an effort to secure, refine, and supplement the relation between central supermassive black hole masses, M {sub •}, and the bulge luminosities of their host galaxies, L {sub bul}, we obtained deep, high spatial resolution K-band images of 35 nearby galaxies with securely measured M {sub •}, using the wide-field WIRCam imager at the Canada-France-Hawaii-Telescope. A dedicated data reduction and sky subtraction strategy was adopted to estimate the brightness and structure of the sky, a critical step when tracing the light distribution of extended objects in the near-infrared. From the final image product, bulge and total magnitudes were extracted via two-dimensional profile fitting. As a first order approximation, all galaxies were modeled using a simple Sérsic-bulge+exponential-disk decomposition. However, we found that such models did not adequately describe the structure that we observed in a large fraction of our sample galaxies which often include cores, bars, nuclei, inner disks, spiral arms, rings, and envelopes. In such cases, we adopted profile modifications and/or more complex models with additional components. The derived bulge magnitudes are very sensitive to the details and number of components used in the models, although total magnitudes remain almost unaffected. Usually, but not always, the luminosities and sizes of the bulges are overestimated when a simple bulge+disk decomposition is adopted in lieu of a more complex model. Furthermore, we found that some spheroids are not well fit when the ellipticity of the Sérsic model is held fixed. This paper presents the details of the image processing and analysis, while we discuss how model-induced biases and systematics in bulge magnitudes impact the M {sub •}-L {sub bul} relation in a companion paper.

  15. Bulge Growth and Quenching Since Z=2.5 in Candels/3D-HST

    Science.gov (United States)

    Lang, Phillip; Wuyts, Stijn; Somerville, Rachel S.; Schreiber, Natascha M. Foerster; Genzel, Reinhard; Bell, Eric F.; Brammer, Gabe; Dekel, Avishai; Faber, Sandra M.; Ferguson, Henry C.; hide

    2014-01-01

    Exploiting the deep high-resolution imaging of all 5 CANDELS fields, and accurate redshift informationprovided by 3D-HST, we investigate the relation between structure and stellar populations fora mass-selected sample of 6764 galaxies above 1010 M, spanning the redshift range 0.5 z 2.5.For the first time, we fit 2-dimensional models comprising a single Sersic fit and two-component (i.e.,bulge + disk) decompositions not only to the H-band light distributions, but also to the stellar massmaps reconstructed from resolved stellar population modeling. We confirm that the increased bulgeprominence among quiescent galaxies, as reported previously based on rest-optical observations, remainsin place when considering the distributions of stellar mass. Moreover, we observe an increaseof the typical Sersic index and bulge-to-total ratio (with median BT reaching 40-50) among starforminggalaxies above 1011 M. Given that quenching for these most massive systems is likely tobe imminent, our findings suggest that significant bulge growth precedes a departure from the starformingmain sequence. We demonstrate that the bulge mass (and ideally knowledge of the bulge andtotal mass) is a more reliable predictor of the star-forming versus quiescent state of a galaxy thanthe total stellar mass. The same trends are predicted by the state-of-the-art semi-analytic model bySomerville et al. In the latter, bulges and black holes grow hand in hand through merging andordisk instabilities, and AGN-feedback shuts off star formation. Further observations will be requiredto pin down star formation quenching mechanisms, but our results imply they must be internal to thegalaxies and closely associated with bulge growth.

  16. Twenty lectures on thermodynamics

    CERN Document Server

    Buchdahl, H A

    2013-01-01

    Twenty Lectures on Thermodynamics is a course of lectures, parts of which the author has given various times over the last few years. The book gives the readers a bird's eye view of phenomenological and statistical thermodynamics. The book covers many areas in thermodynamics such as states and transition; adiabatic isolation; irreversibility; the first, second, third and Zeroth laws of thermodynamics; entropy and entropy law; the idea of the application of thermodynamics; pseudo-states; the quantum-static al canonical and grand canonical ensembles; and semi-classical gaseous systems. The text

  17. Introduction to applied thermodynamics

    CERN Document Server

    Helsdon, R M; Walker, G E

    1965-01-01

    Introduction to Applied Thermodynamics is an introductory text on applied thermodynamics and covers topics ranging from energy and temperature to reversibility and entropy, the first and second laws of thermodynamics, and the properties of ideal gases. Standard air cycles and the thermodynamic properties of pure substances are also discussed, together with gas compressors, combustion, and psychrometry. This volume is comprised of 16 chapters and begins with an overview of the concept of energy as well as the macroscopic and molecular approaches to thermodynamics. The following chapters focus o

  18. Rational extended thermodynamics

    CERN Document Server

    Müller, Ingo

    1998-01-01

    Ordinary thermodynamics provides reliable results when the thermodynamic fields are smooth, in the sense that there are no steep gradients and no rapid changes. In fluids and gases this is the domain of the equations of Navier-Stokes and Fourier. Extended thermodynamics becomes relevant for rapidly varying and strongly inhomogeneous processes. Thus the propagation of high­ frequency waves, and the shape of shock waves, and the regression of small-scale fluctuation are governed by extended thermodynamics. The field equations of ordinary thermodynamics are parabolic while extended thermodynamics is governed by hyperbolic systems. The main ingredients of extended thermodynamics are • field equations of balance type, • constitutive quantities depending on the present local state and • entropy as a concave function of the state variables. This set of assumptions leads to first order quasi-linear symmetric hyperbolic systems of field equations; it guarantees the well-posedness of initial value problems and f...

  19. A new look at the kinematics of the bulge from an N-body model

    Science.gov (United States)

    Gómez, A.; Di Matteo, P.; Stefanovitch, N.; Haywood, M.; Combes, F.; Katz, D.; Babusiaux, C.

    2016-05-01

    By using an N-body simulation of a bulge that was formed via a bar instability mechanism, we analyse the imprints of the initial (I.e. before bar formation) location of stars on the bulge kinematics, in particular on the heliocentric radial velocity distribution of bulge stars. Four different latitudes were considered: b = -4°, -6°, -8°, and -10°, along the bulge minor axis as well as outside it, at l = ± 5° and l = ± 10°. The bulge X-shaped structure comprises stars that formed in the disk at different locations. Stars formed in the outer disk, beyond the end of the bar, which are part of the boxy peanut-bulge structure may show peaks in the velocity distributions at positive and negative heliocentric radial velocities with high absolute values that can be larger than 100 km s-1, depending on the observed direction. In some cases the structure of the velocity field is more complex and several peaks are observed. Stars formed in the inner disk, the most numerous, contribute predominantly to the X-shaped structure and present different kinematic characteristics. They display a rather symmetric velocity distribution and a smaller fraction of high-velocity stars. The stellar stream motion, which is induced by the bar changes with the star initial position, can reach more than 40 km s-1 for stars that originated in the external disk, depending on the observed direction. Otherwise it is smaller than approximately 20 km s-1. In all cases, it decreases from b = -4° to -10°. Our results may enable us to interpret the cold high-velocity peak observed in the APOGEE commissioning data, as well as the excess of high-velocity stars in the near and far arms of the X-shaped structure at l = 0° and b = -6°. When compared with real data, the kinematic picture becomes more complex due to the possible presence in the observed samples of classical bulge and/or thick disk stars. Overall, our results point to the existence of complex patterns and structures in the bulge

  20. Extremely metal-poor stars from the cosmic dawn in the bulge of the Milky Way.

    Science.gov (United States)

    Howes, L M; Casey, A R; Asplund, M; Keller, S C; Yong, D; Nataf, D M; Poleski, R; Lind, K; Kobayashi, C; Owen, C I; Ness, M; Bessell, M S; Da Costa, G S; Schmidt, B P; Tisserand, P; Udalski, A; Szymański, M K; Soszyński, I; Pietrzyński, G; Ulaczyk, K; Wyrzykowski, Ł; Pietrukowicz, P; Skowron, J; Kozłowski, S; Mróz, P

    2015-11-26

    The first stars are predicted to have formed within 200 million years after the Big Bang, initiating the cosmic dawn. A true first star has not yet been discovered, although stars with tiny amounts of elements heavier than helium ('metals') have been found in the outer regions ('halo') of the Milky Way. The first stars and their immediate successors should, however, preferentially be found today in the central regions ('bulges') of galaxies, because they formed in the largest over-densities that grew gravitationally with time. The Milky Way bulge underwent a rapid chemical enrichment during the first 1-2 billion years, leading to a dearth of early, metal-poor stars. Here we report observations of extremely metal-poor stars in the Milky Way bulge, including one star with an iron abundance about 10,000 times lower than the solar value without noticeable carbon enhancement. We confirm that most of the metal-poor bulge stars are on tight orbits around the Galactic Centre, rather than being halo stars passing through the bulge, as expected for stars formed at redshifts greater than 15. Their chemical compositions are in general similar to typical halo stars of the same metallicity although intriguing differences exist, including lower abundances of carbon.

  1. VizieR Online Data Catalog: SDSS bulge, disk and total stellar mass estimates (Mendel+, 2014)

    Science.gov (United States)

    Mendel, J. T.; Simard, L.; Palmer, M.; Ellison, S. L.; Patton, D. R.

    2014-01-01

    We present a catalog of bulge, disk, and total stellar mass estimates for ~660000 galaxies in the Legacy area of the Sloan Digital Sky Survey Data (SDSS) Release 7. These masses are based on a homogeneous catalog of g- and r-band photometry described by Simard et al. (2011, Cat. J/ApJS/196/11), which we extend here with bulge+disk and Sersic profile photometric decompositions in the SDSS u, i, and z bands. We discuss the methodology used to derive stellar masses from these data via fitting to broadband spectral energy distributions (SEDs), and show that the typical statistical uncertainty on total, bulge, and disk stellar mass is ~0.15 dex. Despite relatively small formal uncertainties, we argue that SED modeling assumptions, including the choice of synthesis model, extinction law, initial mass function, and details of stellar evolution likely contribute an additional 60% systematic uncertainty in any mass estimate based on broadband SED fitting. We discuss several approaches for identifying genuine bulge+disk systems based on both their statistical likelihood and an analysis of their one-dimensional surface-brightness profiles, and include these metrics in the catalogs. Estimates of the total, bulge and disk stellar masses for both normal and dust-free models and their uncertainties are made publicly available here. (4 data files).

  2. Proof of safety against bulging of cooling tower shells without and with stiffening rings

    Energy Technology Data Exchange (ETDEWEB)

    Zerna, W.; Mungan, I.; Koepper, H.D.

    1985-10-01

    The proof of safety against bulging described here is based on the experimental and numerical results of research done up to now, and represents a realistic approximation for the measuring of bulges of cooling tower shells without rings and with stiffening rings. The process is characterized by the fact that the proof of safety against bulges refers to stresses, not to loads, and therefore, a local check is made instead of a global one. In this way it is possible to take wind loads and other non-rotation symmetrical loads into account in a realistic way. Research is continuing in this field. Systematic extensive bulging tests are being done at present in a wind tunnel, in the context of a research project. Using measurements on unstiffened and stiffened cooling tower models, the bulging stress conditions under the influence of wind are determined and compared with those which occur with rotation symmetrical loads. The previous assessment of wind tunnel experiments has shown good agreement between the two series of experiments. (orig.).

  3. Disk and Bulge Morphology of WFPC2 Galaxies: The HUBBLE SPACE TELESCOPE Medium Deep Survey

    Science.gov (United States)

    Ratnatunga, Kavan U.; Griffiths, Richard E.; Ostrander, Eric J.

    1999-07-01

    Quantitative morphological and structural parameters are estimated for galaxies detected in Hubble Space Telescope observations of WFPC2 survey fields. A modeling approach based on maximum likelihood has been developed for two-dimensional decomposition of faint undersampled galaxy images into components of disk and bulge morphology. Decomposition can be achieved for images down to F814W(I)~23.0, F606W(V)~23.8, and F450W(B)~23.3 mag in WFPC2 exposures of 1 hr. We discuss details of the fitting procedure and present the observed distributions of magnitude, color, effective half-light radius, disk and bulge axis ratios, bulge-to-(disk+bulge) flux ratio, bulge-to-disk half-light radius ratio, and surface brightness. We also discuss the various selection limits on the measured parameters. The Medium Deep Survey catalogs and images of random pure parallel fields and other similar archival primary WFPC2 fields have been made available via the Internet with a searchable browser interface to the database.

  4. Notch signaling in bulge stem cells is not required for selection of hair follicle fate

    Science.gov (United States)

    Demehri, Shadmehr; Kopan, Raphael

    2009-01-01

    Summary Notch signaling plays an important role in hair follicle maintenance, and it has been suggested that Notch is also required for follicular fate selection by adult hair follicle stem cells in the bulge. Here we demonstrate that, on the contrary, Notch signaling in bi-potential bulge stem cells or their uncommitted descendents acts to suppress the epidermal fate choice, thus ensuring follicular fate selection. To examine the role of Notch signaling in adult hair follicle stem cells, we used a Krt1-15-CrePR1 transgenic mouse line to delete Rbpj or all Notch proteins specifically in the bulge stem cells. We conclusively determined that in the absence of Notch signaling, bulge stem cell descendents retain their capacity to execute the follicular differentiation program but fail to maintain it owing to their genetic deficiency. The defect in terminal differentiation caused the diversion of Notch-deficient hair follicles to epidermal cysts, and the presence of wild-type cells could not prevent this conversion. Importantly, our analysis revealed that a functional Notch signaling pathway was required to block bulge stem cells from migrating into, and assuming the fate of, interfollicular epidermis. Taken together, our findings yield detailed insight into the function of Notch signaling in hair follicle stem cells and reveal the mechanism of the replacement of Notch-deficient adult hair follicles by epidermal cysts. PMID:19211676

  5. An introduction to equilibrium thermodynamics

    CERN Document Server

    Morrill, Bernard; Hartnett, James P; Hughes, William F

    1973-01-01

    An Introduction to Equilibrium Thermodynamics discusses classical thermodynamics and irreversible thermodynamics. It introduces the laws of thermodynamics and the connection between statistical concepts and observable macroscopic properties of a thermodynamic system. Chapter 1 discusses the first law of thermodynamics while Chapters 2 through 4 deal with statistical concepts. The succeeding chapters describe the link between entropy and the reversible heat process concept of entropy; the second law of thermodynamics; Legendre transformations and Jacobian algebra. Finally, Chapter 10 provides a

  6. The Globular Clusters of the Galactic Bulge: Results from Multiwavelength Follow-up Imaging

    Science.gov (United States)

    Cohen, Roger; Geisler, Doug; Mauro, Francesco; Alonso Garcia, Javier; Hempel, Maren; Sarajedini, Ata

    2018-01-01

    The Galactic globular clusters (GGCs) located towards the bulge of the Milky Way suffer from severe total and differential extinction and high field star densities. They have therefore been systematically excluded from deep, large-scale homogenous GGC surveys, and will present a challenge for Gaia. Meanwhile, existing observations of bulge GGCs have revealed tantalizing hints that they hold clues to Galactic formation and evolution not found elsewhere. Therefore, in order to better characterize these poorly studied stellar systems and place them in the context of their optically well-studied counterparts, we have undertaken imaging programs at optical and near-infrared wavelengths. We describe these programs and present a variety of results, including self-consistent measurement of bulge GGC ages and structural parameters. The limitations imposed by spatially variable extinction and extinction law are highlighted, along with the complimentary nature of forthcoming facilities, allowing us to finally complete our picture of the Milky Way GGC system.

  7. [An undamaged bulge in epsilon is essential for initiating priming of DHBV reverse transcriptase].

    Science.gov (United States)

    Hu, Kang-Hong; Feng, Hui; Li, Hui

    2009-07-01

    Previously, we have established an epsilon library and selected out a series of RNA aptamers with higher affinity to P protein based on the in vitro Systematic Evolution of Ligands by Exponential Enrichment (SELEX) in duck hepatitis B virus (DHBV) system. In order to study the structural elements within the epsilon that is essential for initiating priming of HBV reverse transcriptase (P protein), all selected aptamers were subjected to in vitro priming assay and RNA secondary structure probing. We found that all those aptamers supporting priming had an undamaged bulge, while those lacking of the bulge no more support priming. Our results suggest an undamaged bulge within Depsilon is indispensable for initiating priming of P protein.

  8. The SWELLS survey - VI. Hierarchical inference of the initial mass functions of bulges and discs

    DEFF Research Database (Denmark)

    Brewer, Brendon J.; Marshal, Philip J.; Auger, Matthew W.

    2014-01-01

    early-type galaxies, while this IMF is inconsistent with the properties of less massive, later-type galaxies. These discoveries motivate the hypothesis that the IMF may vary (possibly very slightly) across galaxies and across components of individual galaxies (e.g. bulges versus discs). In this paper......, we use a sample of 19 late-type strong gravitational lenses from the Sloan WFC Edge-on Late-type Lens Survey (SWELLS) to investigate the IMFs of the bulges and discs in late-type galaxies. We perform a joint analysis of the galaxies' total masses (constrained by strong gravitational lensing...... mtot with in the aperture, we find that the bulges of the galaxies cannot have IMFs heavier (i.e. implying high mass per unit luminosity) than Salpeter, while the disc IMFs are not well constrained by this data set.We also discuss the necessity for hierarchical modelling when combining incomplete...

  9. Thermodynamics of Bioreactions.

    Science.gov (United States)

    Held, Christoph; Sadowski, Gabriele

    2016-06-07

    Thermodynamic principles have been applied to enzyme-catalyzed reactions since the beginning of the 1930s in an attempt to understand metabolic pathways. Currently, thermodynamics is also applied to the design and analysis of biotechnological processes. The key thermodynamic quantity is the Gibbs energy of reaction, which must be negative for a reaction to occur spontaneously. However, the application of thermodynamic feasibility studies sometimes yields positive Gibbs energies of reaction even for reactions that are known to occur spontaneously, such as glycolysis. This article reviews the application of thermodynamics in enzyme-catalyzed reactions. It summarizes the basic thermodynamic relationships used for describing the Gibbs energy of reaction and also refers to the nonuniform application of these relationships in the literature. The review summarizes state-of-the-art approaches that describe the influence of temperature, pH, electrolytes, solvents, and concentrations of reacting agents on the Gibbs energy of reaction and, therefore, on the feasibility and yield of biological reactions.

  10. What the Milky Way bulge reveals about the initial metallicity gradients in the disc

    Science.gov (United States)

    Fragkoudi, F.; Di Matteo, P.; Haywood, M.; Khoperskov, S.; Gomez, A.; Schultheis, M.; Combes, F.; Semelin, B.

    2017-11-01

    We use APOGEE DR13 data to examine the metallicity trends in the Milky Way (MW) bulge and we explore their origin by comparing two N-body models of isolated galaxies that develop a bar and a boxy/peanut (b/p) bulge. Both models have been proposed as scenarios for reconciling a disc origin of the MW bulge with a negative vertical metallicity gradient. The first model is a superposition of co-spatial, i.e. overlapping, disc populations with different scale heights, kinematics, and metallicities. In this model the thick, metal-poor, and centrally concentrated disc populations contribute significantly to the stellar mass budget in the inner galaxy. The second model is a single disc with an initial steep radial metallicity gradient; this disc is mapped by the bar into the b/p bulge in such a way that the vertical metallicity gradient of the MW bulge is reproduced, as has been shown already in previous works in the literature. However, as we show here, the latter model does not reproduce the positive longitudinal metallicity gradient of the inner disc, nor the metal-poor innermost regions seen in the data. On the other hand, the model with co-spatial thin and thick disc populations reproduces all the aforementioned trends. We therefore see that it is possible to reconcile a (primarily) disc origin for the MW bulge with the observed trends in metallicity by mapping the inner thin and thick discs of the MW into a b/p. For this scenario to reproduce the observations, the α-enhanced, metal-poor, thick disc populations must have a significant mass contribution in the inner regions, as has been suggested for the Milky Way.

  11. On thermodynamics and gravity

    Science.gov (United States)

    Nagle, Ian

    2017-09-01

    A new entropic gravity inspired derivation of general relativity from thermodynamics is presented. This generalizes the "Thermodynamics of Spacetime" approach by T. Jacobson, which relies on the null Raychaudhuri evolution equation. Here the rest of the first law of thermodynamics is incorporated by using the null Damour-Navier-Stokes equation, known from the membrane paradigm for describing the tangential flow of deformations along a horizon.

  12. Stochastic Thermodynamics of Learning

    Science.gov (United States)

    Goldt, Sebastian; Seifert, Udo

    2017-01-01

    Virtually every organism gathers information about its noisy environment and builds models from those data, mostly using neural networks. Here, we use stochastic thermodynamics to analyze the learning of a classification rule by a neural network. We show that the information acquired by the network is bounded by the thermodynamic cost of learning and introduce a learning efficiency η ≤1 . We discuss the conditions for optimal learning and analyze Hebbian learning in the thermodynamic limit.

  13. Thermodynamical journey in plant biology

    Directory of Open Access Journals (Sweden)

    Adelin eBarbacci

    2015-06-01

    Full Text Available Nonequilibrium irreversible thermodynamics constitute a meaningful point of view suitable to explore life with a rich paradigm. This analytical framework can be used to span the gap from molecular processes to plant function and shows great promise to create a holistic description of life. Since living organisms dissipate energy, exchange entropy and matter with their environment, they can be assimilated to dissipative structures. This concept inherited from nonequilibrium thermodynamics has four properties which defines a scale independent framework suitable to provide a simpler and more comprehensive view of the highly complex plant biology. According to this approach, a biological process is modeled as an avalanche of dissipative structures. Each dissipative structure, corresponds to an unitary biological process, which is initiated by the amplification of a fluctuation. Evolution of the process leads to the breakage of the system symmetry and to the export of entropy. Exporting entropy to the surrounding environment corresponds to collecting information about it. Biological actors which break the symmetry of the system and which store information are by consequence, key actors on which experiments and data analysis focus most. This paper aims at illustrating properties of dissipative structure through familiar examples and thus initiating the dialogue between nonequilibrium thermodynamics and plant biology.

  14. Detection of a Distinct Pseudobulge Hidden Inside the ``Box-Shaped Bulge'' of NGC 4565

    Science.gov (United States)

    Barentine, J. C.; Kormendy, J.

    2009-12-01

    N-body simulations show that “box-shaped bulges” of edge-on galaxies are not bulges at all: they are bars seen side on. The two components that we readily see in edge-on Sb galaxies like NGC 4565 are a disk and a bar. But face-on SBb galaxies always show a disk, a bar, and a (pseudo)bulge. Where is the (pseudo)bulge in NGC 4565? We use archival Hubble Space Telescope K-band images and Spitzer Space Telescope 3.6 μm wavelength images to penetrate the dust in NGC 4565. We find a high surface brightness central stellar component that is clearly distinct from the boxy bar and from the galaxy’s disk. Its minor-axis profile has a Sérsic index of 1.33±0.12, so it is a pseudobulge. The pseudobulge has the smallest scale height (˜90 pc) of any component in the galaxy. This is in contrast to a scale height of ˜740 pc for the boxy bar plus thin disk. The disky pseudobulge is also much less luminous than the boxy bar, so the true pseudobulge-to-total luminosity ratio of the galaxy is much less than previously thought. We infer that the (pseudo)bulge-to-total luminosity ratios of edge-on galaxies with box-shaped bulges have generally been overestimated. Therefore more galaxies than we have recognized contain little or no evidence of a merger-built classical bulge. This presents a challenge to our picture of galaxy formation by hierarchical clustering, because it is difficult to grow big galaxies without also making a big classical bulge. Solving the puzzle of the “missing pseudobulge” in NGC 4565 further increases our confidence that we understand box-shaped bulges correctly as edge-on bars. This in turn supports our developing picture of the formation of pseudobulges—both edge-on bars and disky central components—by secular evolution in isolated galaxies.

  15. Methods of thermodynamics

    CERN Document Server

    Reiss, Howard

    1997-01-01

    Since there is no shortage of excellent general books on elementary thermodynamics, this book takes a different approach, focusing attention on the problem areas of understanding of concept and especially on the overwhelming but usually hidden role of ""constraints"" in thermodynamics, as well as on the lucid exposition of the significance, construction, and use (in the case of arbitrary systems) of the thermodynamic potential. It will be especially useful as an auxiliary text to be used along with any standard treatment.Unlike some texts, Methods of Thermodynamics does not use statistical m

  16. Thermodynamic and Quantum Thermodynamic Analyses of Brownian Movement

    OpenAIRE

    Gyftopoulos, Elias P.

    2006-01-01

    Thermodynamic and quantum thermodynamic analyses of Brownian movement of a solvent and a colloid passing through neutral thermodynamic equilibrium states only. It is shown that Brownian motors and E. coli do not represent Brownian movement.

  17. Thermodynamics and heat power

    CERN Document Server

    Granet, Irving

    2014-01-01

    Fundamental ConceptsIntroductionThermodynamic SystemsTemperatureForce and MassElementary Kinetic Theory of GasesPressureReviewKey TermsEquations Developed in This ChapterQuestionsProblemsWork, Energy, and HeatIntroductionWorkEnergyInternal EnergyPotential EnergyKinetic EnergyHeatFlow WorkNonflow WorkReviewKey TermsEquations Developed in This ChapterQuestionsProblemsFirst Law of ThermodynamicsIntroductionFirst Law of ThermodynamicsNonflow SystemSteady-Flow SystemApplications of First Law of ThermodynamicsReviewKey TermsEquations Developed in This ChapterQuestionsProblemsThe Second Law of ThermodynamicsIntroductionReversibility-Second Law of ThermodynamicsThe Carnot CycleEntropyReviewKey TermsEquations Developed in This ChapterQuestionsProblemsProperties of Liquids and GasesIntroductionLiquids and VaporsThermodynamic Properties of SteamComputerized PropertiesThermodynamic DiagramsProcessesReviewKey TermsEquations Developed in This ChapterQuestionsProblemsThe Ideal GasIntroductionBasic ConsiderationsSpecific Hea...

  18. Equilibrium thermodynamics - Callen's postulational approach

    NARCIS (Netherlands)

    Jongschaap, R.J.J.; Öttinger, Hans Christian

    2001-01-01

    In order to provide the background for nonequilibrium thermodynamics, we outline the fundamentals of equilibrium thermodynamics. Equilibrium thermodynamics must not only be obtained as a special case of any acceptable nonequilibrium generalization but, through its shining example, it also elucidates

  19. Thermodynamics an engineering approach

    CERN Document Server

    Cengel, Yunus A

    2014-01-01

    Thermodynamics, An Engineering Approach, eighth edition, covers the basic principles of thermodynamics while presenting a wealth of real-world engineering examples so students get a feel for how thermodynamics is applied in engineering practice. This text helps students develop an intuitive understanding by emphasizing the physics and physical arguments. Cengel and Boles explore the various facets of thermodynamics through careful explanations of concepts and use of numerous practical examples and figures, having students develop necessary skills to bridge the gap between knowledge and the confidence to properly apply their knowledge. McGraw-Hill is proud to offer Connect with the eighth edition of Cengel/Boles, Thermodynamics, An Engineering Approach. This innovative and powerful new system helps your students learn more efficiently and gives you the ability to assign homework problems simply and easily. Problems are graded automatically, and the results are recorded immediately. Track individual stude...

  20. Thermodynamics of complexity

    DEFF Research Database (Denmark)

    Westerhoff, Hans V.; Jensen, Peter Ruhdal; Snoep, Jacky L.

    1998-01-01

    Thermodynamics has always been a remarkable science in that it studies macroscopic properties that are only partially determined by the properties of individual molecules. Entropy and free energy only exist in constellations of more than a single molecule (degree of freedom). They are the so...... understanding of this BioComplexity, modem thermodynamic concepts and methods (nonequilibrium thermodynamics, metabolic and hierarchical control analysis) will be needed. We shall propose to redefine nonequilibrium thermodynamics as: The science that aims at understanding the behaviour of nonequilibrium systems...... by taking into account both the molecular properties and the emergent properties that are due to (dys)organisation. This redefinition will free nonequilibrium thermodynamics from the limitations imposed by earlier near-equilibrium assumptions, resolve the duality with kinetics, and bridge the apparent gap...

  1. Ages of galaxy bulges and disks from optical and near-infrared colours

    NARCIS (Netherlands)

    Peletier, RF; Balcells, M; Bender, R; Davies, RL

    1996-01-01

    For a sample of bright nearby early-type galaxies we have obtained surface photometry in bands ranging from U to K. Since the galaxies have inclinations larger than 50 degrees it is easy to separate bulges and disks. By measuring the colours in special regions, we minimize the effects of extinction,

  2. Finite Element Analysis of Bulge Forming of Laser Welding Dimple Jacket

    Directory of Open Access Journals (Sweden)

    Peisi ZHONG

    2015-11-01

    Full Text Available The stress-strain states of the model of laser welded dimple jacket is analyzed using ANSYS/LS-DYNA in order to determine the relation between bulging height and pressure and to achieve the controllability of pressure distension of the jacket. It is shown that in the same conditions, the bulging height increases with the increasing of the bulging pressure and the space of honeycomb. And it will decrease when the thickness of jacket plate changing larger. A table showing the relation between bulging height and pressure is obtained. An experiment using a test panel is conducted to certify the reliability of finite element analysis. It turns out that the data of finite element analysis is coincident with experimental data, which support finite element method based ANSYS/LS-DYNA can be an efficient way to research the laser welded dimple jacket. The relation table is useful as guidance for the fabrication process.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9704

  3. SDSS-IV MaNGA: bulge-disc decomposition of IFU data cubes (BUDDI)

    Science.gov (United States)

    Johnston, Evelyn J.; Häußler, Boris; Aragón-Salamanca, Alfonso; Merrifield, Michael R.; Bamford, Steven; Bershady, Matthew A.; Bundy, Kevin; Drory, Niv; Fu, Hai; Law, David; Nitschelm, Christian; Thomas, Daniel; Roman Lopes, Alexandre; Wake, David; Yan, Renbin

    2017-02-01

    With the availability of large integral field unit (IFU) spectral surveys of nearby galaxies, there is now the potential to extract spectral information from across the bulges and discs of galaxies in a systematic way. This information can address questions such as how these components built up with time, how galaxies evolve and whether their evolution depends on other properties of the galaxy such as its mass or environment. We present bulge-disc decomposition of IFU data cubes (BUDDI), a new approach to fit the two-dimensional light profiles of galaxies as a function of wavelength to extract the spectral properties of these galaxies' discs and bulges. The fitting is carried out using GALFITM, a modified form of GALFIT which can fit multiwaveband images simultaneously. The benefit of this technique over traditional multiwaveband fits is that the stellar populations of each component can be constrained using knowledge over the whole image and spectrum available. The decomposition has been developed using commissioning data from the Sloan Digital Sky Survey-IV Mapping Nearby Galaxies at APO (MaNGA) survey with redshifts z 22 arcsec, but can be applied to any IFU data of a nearby galaxy with similar or better spatial resolution and coverage. We present an overview of the fitting process, the results from our tests, and we finish with example stellar population analyses of early-type galaxies from the MaNGA survey to give an indication of the scientific potential of applying bulge-disc decomposition to IFU data.

  4. The population of single and binary white dwarfs of the Galactic bulge

    Science.gov (United States)

    Torres, S.; García-Berro, E.; Cojocaru, R.; Calamida, A.

    2018-02-01

    Recent Hubble Space Telescope observations have unveiled the white dwarf cooling sequence of the Galactic bulge. Although the degenerate sequence can be well fitted employing the most up-to-date theoretical cooling sequences, observations show a systematic excess of red objects that cannot be explained by the theoretical models of single carbon-oxygen white dwarfs of the appropriate masses. Here we present a population synthesis study of the white dwarf cooling sequence of the Galactic bulge that takes into account the populations of both single white dwarfs and binary systems containing at least one white dwarf. These calculations incorporate state-of-the-art cooling sequences for white dwarfs with hydrogen-rich and hydrogen-deficient atmospheres, for both white dwarfs with carbon-oxygen and helium cores, and also take into account detailed prescriptions of the evolutionary history of binary systems. Our Monte Carlo simulator also incorporates all the known observational biases. This allows us to model with a high degree of realism the white dwarf population of the Galactic bulge. We find that the observed excess of red stars can be partially attributed to white dwarf plus main sequence binaries, and to cataclysmic variables or dwarf novae. Our best fit is obtained with a higher binary fraction and an initial mass function slope steeper than standard values, as well as with the inclusion of differential reddening and blending. Our results also show that the possible contribution of double degenerate systems or young and thick-disk bulge stars is negligible.

  5. Photoionization modelling of planetary nebulae - II. Galactic bulge nebulae, a comparison with literature results

    NARCIS (Netherlands)

    van Hoof, PAM; Van de Steene, GC

    1999-01-01

    We have constructed photoionization models of five galactic bulge planetary nebulae using our automatic method, which enables a fully self-consistent determination of the physical parameters of a planetary nebula. The models are constrained using the spectrum, the IRAS and radio fluxes and the

  6. Black Holes and Galactic Density Cusps I Radial Orbit Cusps and Bulges

    CERN Document Server

    Henriksen, Richard N; Macmillan, Joseph D

    2011-01-01

    Aims. In this paper we study density cusps made from radial orbits that may contain central black holes. The actual co-eval self-similar growth would not distinguish between the central object and the surroundings. Methods. To study the environment of an existing black hole we seek distribution functions that may contain a black hole and that retain at least a memory of self-similarity. We refer to the environment in brief as the 'bulge' or sometimes the 'halo'. This depends on whether the black hole is a true singularity dominating its halo or rather a core mass concentration that dominates a larger bulge. The hierarchy might extend to include galactic bulge and halo. Results.We find simple descriptions of simulated collisionless matter in the process of examining the presence of central masses. The Fridmann & Polyachenko distribution function describes co-eval growth of a bulge and black hole that might explain the observed mass correlation. Conclusions. We derive our results from first principles assum...

  7. The age and structure of the Galactic bulge from Mira variables

    Science.gov (United States)

    Catchpole, Robin M.; Whitelock, Patricia A.; Feast, Michael W.; Hughes, Shaun M. G.; Irwin, Mike; Alard, Christophe

    2016-01-01

    We report periods and JHKL observations for 643 oxygen-rich Mira variables found in two outer bulge fields at b = -7° and l = ±8° and combine these with data on 8057 inner bulge Miras from the Optical Gravitational Lensing Experiment, MACHO and Two Micron All Sky Survey surveys, which are concentrated closer to the Galactic Centre. Distance moduli are estimated for all these stars. Evidence is given showing that the bulge structure is a function of age. The longer period Miras (log P > 2.6, age ˜5 Gyr and younger) show clear evidence of a bar structure inclined to the line of sight in both the inner and outer regions. The distribution of the shorter period (metal-rich globular cluster age) Miras appears spheroidal in the outer bulge. In the inner region these old stars are also distributed differently from the younger ones and possibly suggest a more complex structure. These data suggest a distance to the Galactic Centre, R0, of 8.9 kpc with an estimated uncertainty of ˜0.4 kpc. The possible effect of helium enrichment on our conclusions is discussed.

  8. Bulge formation and necking in a polymer tube under dynamic expansion

    DEFF Research Database (Denmark)

    Lindgreen, Britta; Tvergaard, Viggo; Needleman, Alan

    2008-01-01

    Bulging and necking in long thin polymer tubes subjected to increasing internal pressure are analysed numerically. The polymer is characterized by a finite strain elastic-viscoplastic constitutive relation and the calculations are carried out using a dynamic finite element program. Two types...

  9. Light, alpha, and Fe-peak element abundances in the galactic bulge

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Christian I. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-15, Cambridge, MA 02138 (United States); Rich, R. Michael [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States); Kobayashi, Chiaki [Centre for Astrophysics Research, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Kunder, Andrea [Leibniz-Institute für Astrophysik Potsdam (AIP), Ander Sternwarte 16, D-14482, Potsdam (Germany); Koch, Andreas, E-mail: cjohnson@cfa.harvard.edu, E-mail: rmr@astro.ucla.edu, E-mail: c.kobayashi@herts.ac.uk, E-mail: akunder@aip.de, E-mail: akoch@lsw.uni-heidelberg.de [Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, Heidelberg (Germany)

    2014-10-01

    We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l, b) = (+5.25,–3.02) and (0,–12). The (+5.25,–3.02) field also includes observations of the bulge globular cluster NGC 6553. The results are based on high-resolution (R ∼ 20,000), high signal-to-noise ration (S/N ≳ 70) FLAMES-GIRAFFE spectra obtained through the European Southern Observatory archive. However, we only selected a subset of the original observations that included spectra with both high S/N and that did not show strong TiO absorption bands. This work extends previous analyses of this data set beyond Fe and the α-elements Mg, Si, Ca, and Ti. While we find reasonable agreement with past work, the data presented here indicate that the bulge may exhibit a different chemical composition than the local thick disk, especially at [Fe/H] ≳ –0.5. In particular, the bulge [α/Fe] ratios may remain enhanced to a slightly higher [Fe/H] than the thick disk, and the Fe-peak elements Co, Ni, and Cu appear enhanced compared to the disk. There is also some evidence that the [Na/Fe] (but not [Al/Fe]) trends between the bulge and local disk may be different at low and high metallicity. We also find that the velocity dispersion decreases as a function of increasing [Fe/H] for both fields, and do not detect any significant cold, high-velocity populations. A comparison with chemical enrichment models indicates that a significant fraction of hypernovae may be required to explain the bulge abundance trends, and that initial mass functions that are steep, top-heavy (and do not include strong outflow), or truncated to avoid including contributions from stars >40 M {sub ☉} are ruled out, in particular because of disagreement with the Fe-peak abundance data. For most elements, the NGC 6553 stars exhibit abundance trends nearly identical to comparable metallicity bulge field

  10. The thermodynamics of general and local anesthesia

    CERN Document Server

    Graesboll, Kaare; Heimburg, Thomas

    2014-01-01

    General anesthetics are known to cause depression of the freezing point of transitions in biomembranes. This is a consequence of ideal mixing of the anesthetic drugs in the membrane fluid phase and exclusion from the solid phase. Such a generic law provides physical justification of the famous Meyer-Overton rule. We show here that general anesthetics, barbiturates and local anesthetics all display the same effect on melting transitions. Their effect is reversed by hydrostatic pressure. Thus, the thermodynamic behavior of local anesthetics is very similar to that of general anesthetics. We present a detailed thermodynamic analysis of heat capacity profiles of membranes in the presence of anesthetics. This analysis is able to describe experimentally observed calorimetric profiles and permits prediction of the anesthetic features of arbitrary molecules. In addition, we discuss the thermodynamic origin of the cutoff-effect of long-chain alcohols and the additivity of the effect of general and local anesthetics.

  11. The Thermodynamics of General and Local Anesthesia

    Science.gov (United States)

    Græsbøll, Kaare; Sasse-Middelhoff, Henrike; Heimburg, Thomas

    2014-05-01

    General anesthetics are known to cause depression of the freezing point of transitions in biomembranes. This is a consequence of ideal mixing of the anesthetic drugs in the membrane fluid phase and exclusion from the solid phase. Such a generic law provides physical justification of the famous Meyer-Overton rule. We show here that general anesthetics, barbiturates and local anesthetics all display the same effect on melting transitions. Their effect is reversed by hydrostatic pressure. Thus, the thermodynamic behavior of local anesthetics is very similar to that of general anesthetics. We present a detailed thermodynamic analysis of heat capacity profiles of membranes in the presence of anesthetics. This analysis is able to describe experimentally observed calorimetric profiles and permits prediction of the anesthetic features of arbitrary molecules. In addition, we discuss the thermodynamic origin of the cutoff-effect of long-chain alcohols and the additivity of the effect of general and local anesthetics.

  12. A thermodynamic cycle for the solar cell

    Science.gov (United States)

    Alicki, Robert; Gelbwaser-Klimovsky, David; Jenkins, Alejandro

    2017-03-01

    A solar cell is a heat engine, but textbook treatments are not wholly satisfactory from a thermodynamic standpoint, since they present solar cells as directly converting the energy of light into electricity, and the current in the circuit as maintained by an electrostatic potential. We propose a thermodynamic cycle in which the gas of electrons in the p phase serves as the working substance. The interface between the p and n phases acts as a self-oscillating piston that modulates the absorption of heat from the photons so that it may perform a net positive work during a complete cycle of its motion, in accordance with the laws of thermodynamics. We draw a simple hydrodynamical analogy between this model and the "putt-putt" engine of toy boats, in which the interface between the water's liquid and gas phases serves as the piston. We point out some testable consequences of this model.

  13. Modern engineering thermodynamics

    CERN Document Server

    Balmer, Robert T

    2010-01-01

    Designed for use in a standard two-semester engineering thermodynamics course sequence. The first half of the text contains material suitable for a basic Thermodynamics course taken by engineers from all majors. The second half of the text is suitable for an Applied Thermodynamics course in mechanical engineering programs. The text has numerous features that are unique among engineering textbooks, including historical vignettes, critical thinking boxes, and case studies. All are designed to bring real engineering applications into a subject that can be somewhat abstract and mathematica

  14. Thermodynamics I essentials

    CERN Document Server

    REA, The Editors of

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Thermodynamics I includes review of properties and states of a pure substance, work and heat, energy and the first law of thermodynamics, entropy and the second law of thermodynamics

  15. Advanced thermodynamics engineering

    CERN Document Server

    Annamalai, Kalyan; Jog, Milind A

    2011-01-01

    Thermolab Excel-Based Software for Thermodynamic Properties and Flame Temperatures of Fuels IntroductionImportance, Significance and LimitationsReview of ThermodynamicsMathematical BackgroundOverview of Microscopic/NanothermodynamicsSummaryAppendix: Stokes and Gauss Theorems First Law of ThermodynamicsZeroth LawFirst Law for a Closed SystemQuasi Equilibrium (QE) and Nonquasi-equilibrium (NQE) ProcessesEnthalpy and First LawAdiabatic Reversible Process for Ideal Gas with Constant Specific HeatsFirst Law for an Open SystemApplications of First Law for an Open SystemIntegral and Differential Form

  16. Selected problems in thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Andrianova, T.N.; Dzampov, B.V.; Remizov, S.A.; Zubarev, V.N.

    1981-01-01

    This collection of problems is designed for a course in engineering thermodynamics for engineering and thermophysical disciplines in energy institutes. The problems contain the following fundamentals: first and second laws of thermodynamics, physical state and change of state processes in ideal and real gases, water, steam and moist air; efflux and choking of gases and steam, internal combustion cycles, gas and steam turbines, refrigerators, compressors, as well as problems in chemical thermodynamics. Answers to all problems are given, examples include solutions. The SI system of units is used.

  17. Non-equilibrium thermodynamics

    CERN Document Server

    De Groot, Sybren Ruurds

    1984-01-01

    The study of thermodynamics is especially timely today, as its concepts are being applied to problems in biology, biochemistry, electrochemistry, and engineering. This book treats irreversible processes and phenomena - non-equilibrium thermodynamics.S. R. de Groot and P. Mazur, Professors of Theoretical Physics, present a comprehensive and insightful survey of the foundations of the field, providing the only complete discussion of the fluctuating linear theory of irreversible thermodynamics. The application covers a wide range of topics: the theory of diffusion and heat conduction, fluid dyn

  18. Structure and dynamics of galaxies with a low surface-brightness disc - II. Stellar populations of bulges

    Science.gov (United States)

    Morelli, L.; Corsini, E. M.; Pizzella, A.; Dalla Bontà, E.; Coccato, L.; Méndez-Abreu, J.; Cesetti, M.

    2012-06-01

    We present the radial profiles of the Hβ, Mg and Fe line-strength indices for a sample of eight spiral galaxies with a low-surface-brightness stellar disc and a bulge. The correlations between the central values of the line-strength indices and velocity dispersion are consistent with those known for early-type galaxies and bulges of high-surface-brightness galaxies. The age, metallicity and α/Fe enhancement of the stellar populations in the bulge-dominated region are obtained using stellar population models with variable element abundance ratios. Almost all the sample bulges are characterized by a young stellar population, ongoing star formation and a solar α/Fe enhancement. Their metallicity spans from high to subsolar values. No significant gradient in age and α/Fe enhancement is measured, whereas a negative metallicity gradient is found only in a few cases. These properties suggest that a pure dissipative collapse cannot explain the formation of all the sample bulges and that other phenomena, such as mergers or acquisition events, need to be invoked. Such a picture is also supported by the lack of a correlation between the central value and the gradient of the metallicity in bulges with very low metallicity. The stellar populations of the bulges hosted by low-surface-brightness discs share many properties with those of high-surface-brightness galaxies. Therefore, they are likely to have common formation scenarios and evolution histories. A strong interplay between bulges and discs is ruled out by the fact that, in spite of being hosted by discs with extremely different properties, the bulges of low- and high-surface-brightness discs are remarkably similar. Based on observations made with European Southern Observatory telescopes at the La Silla Paranal Observatory under programmes 76.B-0375 and 80.B-00754.

  19. Workshop on Teaching Thermodynamics

    CERN Document Server

    1985-01-01

    It seemed appropriate to arrange a meeting of teachers of thermodynamics in the United Kingdom, a meeting held in the pleasant surroundings of Emmanuel College, Cambridge, in Sept~mber, 1984. This volume records the ideas put forward by authors, the discussion generated and an account of the action that discussion has initiated. Emphasis was placed on the Teaching of Thermodynamics to degree-level students in their first and second years. The meeting, a workshop for practitioners in which all were expected to take part, was remarkably well supported. This was notable in the representation of essentially every UK university and polytechnic engaged in teaching engineering thermodynamics and has led to a stimulating spread of ideas. By intention, the emphasis for attendance was put on teachers of engineering concerned with thermodynamics, both mechanical and chemical engineering disciplines. Attendance from others was encouraged but limited as follows: non-engineering acad­ emics, 10%, industrialists, 10%. The ...

  20. Elements of chemical thermodynamics

    CERN Document Server

    Nash, Leonard K

    2005-01-01

    This survey of purely thermal data in calculating the position of equilibrium in a chemical reaction highlights the physical content of thermodynamics, as distinct from purely mathematical aspects. 1970 edition.

  1. Theoretical physics 5 thermodynamics

    CERN Document Server

    Nolting, Wolfgang

    2017-01-01

    This concise textbook offers a clear and comprehensive introduction to thermodynamics, one of the core components of undergraduate physics courses. It follows on naturally from the previous volumes in this series, defining macroscopic variables, such as internal energy, entropy and pressure,together with thermodynamic principles. The first part of the book introduces the laws of thermodynamics and thermodynamic potentials. More complex themes are covered in the second part of the book, which describes phases and phase transitions in depth. Ideally suited to undergraduate students with some grounding in classical mechanics, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series cove...

  2. Elementary chemical thermodynamics

    CERN Document Server

    Mahan, Bruce H

    1963-01-01

    This text introduces thermodynamic principles in a straightforward manner. Suitable for advanced undergraduates and graduate students, it emphasizes chemical applications and physical interpretations and simplifies mathematical development. 1964 edition.

  3. Electrochemical thermodynamic measurement system

    Science.gov (United States)

    Reynier, Yvan [Meylan, FR; Yazami, Rachid [Los Angeles, CA; Fultz, Brent T [Pasadena, CA

    2009-09-29

    The present invention provides systems and methods for accurately characterizing thermodynamic and materials properties of electrodes and electrochemical energy storage and conversion systems. Systems and methods of the present invention are configured for simultaneously collecting a suite of measurements characterizing a plurality of interconnected electrochemical and thermodynamic parameters relating to the electrode reaction state of advancement, voltage and temperature. Enhanced sensitivity provided by the present methods and systems combined with measurement conditions that reflect thermodynamically stabilized electrode conditions allow very accurate measurement of thermodynamic parameters, including state functions such as the Gibbs free energy, enthalpy and entropy of electrode/electrochemical cell reactions, that enable prediction of important performance attributes of electrode materials and electrochemical systems, such as the energy, power density, current rate and the cycle life of an electrochemical cell.

  4. Chemical engineering thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Newman, S.A. (ed.)

    1983-01-01

    This book contains most of the papers presented at the thermodynamics sessions of the Second World Congress of Chemical Engineering held October 4-9, 1981 in Montreal, Canada. The chapters of the book have been categorized into the following areas: (1) Phase Equilibria, (2) Equations of State, (3) Electrolytes, and (4) Other Thermodynamic Topics. Topics presented in the chapters include: thermophysical data banks; group contribution methods applied to phase equilibrai; equations of state for vapor-liquid and liquid-liquid equilibria with applications to design; vapor-liquid equilibria in systems including bitumen, heavy oil and coal-derived liquids; thermodynamics of polar substances; coal char thermochemical data; chemical equilibria; petroleum fraction thermodynamics and sour water vapor-liquid equilibria. (DP)

  5. Polyelectrolytes thermodynamics and rheology

    CERN Document Server

    P M, Visakh; Picó, Guillermo Alfredo

    2014-01-01

    This book discusses current development of theoretical models and experimental findings on the thermodynamics of polyelectrolytes. Particular emphasis is placed on the rheological description of polyelectrolyte solutions and hydrogels.

  6. General and Statistical Thermodynamics

    CERN Document Server

    Tahir-Kheli, Raza

    2012-01-01

    This textbook explains completely the general and statistical thermodynamics. It begins with an introductory statistical mechanics course, deriving all the important formulae meticulously and explicitly, without mathematical short cuts. The main part of the book deals with the careful discussion of the concepts and laws of thermodynamics, van der Waals, Kelvin and Claudius theories, ideal and real gases, thermodynamic potentials, phonons and all the related aspects. To elucidate the concepts introduced and to provide practical problem solving support, numerous carefully worked examples are of great value for students. The text is clearly written and punctuated with many interesting anecdotes. This book is written as main textbook for upper undergraduate students attending a course on thermodynamics.

  7. Elements of statistical thermodynamics

    CERN Document Server

    Nash, Leonard K

    2006-01-01

    Encompassing essentially all aspects of statistical mechanics that appear in undergraduate texts, this concise, elementary treatment shows how an atomic-molecular perspective yields new insights into macroscopic thermodynamics. 1974 edition.

  8. The Gaia-ESO Survey: Low-α element stars in the Galactic bulge

    Science.gov (United States)

    Recio-Blanco, A.; Rojas-Arriagada, A.; de Laverny, P.; Mikolaitis, S.; Hill, V.; Zoccali, M.; Fernández-Trincado, J. G.; Robin, A. C.; Babusiaux, C.; Gilmore, G.; Randich, S.; Alfaro, E.; Allende Prieto, C.; Bragaglia, A.; Carraro, G.; Jofré, P.; Lardo, C.; Monaco, L.; Morbidelli, L.; Zaggia, S.

    2017-06-01

    We take advantage of the Gaia-ESO Survey iDR4 bulge data to search for abundance anomalies that could shed light on the composite nature of the Milky Way bulge. The α-element (Mg, Si, and whenever available, Ca) abundances, and their trends with Fe abundances have been analysed for a total of 776 bulge stars. In addition, the aluminum abundances and their ratio to Fe and Mg have also been examined. Our analysis reveals the existence of low-α element abundance stars with respect to the standard bulge sequence in the [α/ Fe] versus [Fe/H] plane. Eighteen objects present deviations in [α/ Fe] ranging from 2.1 to 5.3σ with respect to the median standard value. Those stars do not show Mg-Al anti-correlation patterns. Incidentally, this sign of the existence of multiple stellar populations is reported firmly for the first time for the bulge globular cluster NGC 6522. The identified low-α abundance stars have chemical patterns that are compatible with those of the thin disc. Their link with massive dwarf galaxies accretion seems unlikely, as larger deviations in α abundance and Al would be expected. The vision of a bulge composite nature and a complex formation process is reinforced by our results. The approach used, which is a multi-method and model-driven analysis of high resolution data, seems crucial to reveal this complexity. Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 188.B-3002. These data products have been processed by the Cambridge Astronomy Survey Unit (CASU) at the Institute of Astronomy, University of Cambridge, and by the FLAMES/UVES reduction team at INAF/Osservatorio Astrofisico di Arcetri. These data have been obtained from the Gaia-ESO Survey Data Archive, and prepared and hosted by the Wide Field Astronomy Unit, Institute for Astronomy, University of Edinburgh, which is funded by the UK Science and Technology Facilities Council.

  9. Construction of microcanonical entropy on thermodynamic pillars

    Science.gov (United States)

    Campisi, Michele

    2015-05-01

    A question that is currently highly debated is whether the microcanonical entropy should be expressed as the logarithm of the phase volume (volume entropy, also known as the Gibbs entropy) or as the logarithm of the density of states (surface entropy, also known as the Boltzmann entropy). Rather than postulating them and investigating the consequence of each definition, as is customary, here we adopt a bottom-up approach and construct the entropy expression within the microcanonical formalism upon two fundamental thermodynamic pillars: (i) The second law of thermodynamics as formulated for quasistatic processes: δ Q /T is an exact differential, and (ii) the law of ideal gases: P V =kBN T . The first pillar implies that entropy must be some function of the phase volume Ω . The second pillar singles out the logarithmic function among all possible functions. Hence the construction leads uniquely to the expression S =kBlnΩ , that is, the volume entropy. As a consequence any entropy expression other than that of Gibbs, e.g., the Boltzmann entropy, can lead to inconsistencies with the two thermodynamic pillars. We illustrate this with the prototypical example of a macroscopic collection of noninteracting spins in a magnetic field, and show that the Boltzmann entropy severely fails to predict the magnetization, even in the thermodynamic limit. The uniqueness of the Gibbs entropy, as well as the demonstrated potential harm of the Boltzmann entropy, provide compelling reasons for discarding the latter at once.

  10. A New Perspective on Thermodynamics

    CERN Document Server

    Lavenda, Bernard H

    2010-01-01

    Dr. Bernard H. Lavenda has written A New Perspective on Thermodynamics to combine an old look at thermodynamics with a new foundation. The book presents a historical perspective, which unravels the current presentation of thermodynamics found in standard texts, and which emphasizes the fundamental role that Carnot played in the development of thermodynamics. A New Perspective on Thermodynamics will: Chronologically unravel the development of the principles of thermodynamics and how they were conceived by their discoverers Bring the theory of thermodynamics up to the present time and indicate areas of further development with the union of information theory and the theory of means and their inequalities. New areas include nonextensive thermodynamics, the thermodynamics of coding theory, multifractals, and strange attractors. Reintroduce important, yet nearly forgotten, teachings of N.L. Sardi Carnot Highlight conceptual flaws in timely topics such as endoreversible engines, finite-time thermodynamics, geometri...

  11. Forming limit diagram of aluminum AA6063 tubes at high temperatures by bulge tests

    Energy Technology Data Exchange (ETDEWEB)

    Hashemi, Seyed Jalal; Naeini, Hassan Moslemi; Liaghat, Gholamhossein [Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Tafti, Rooholla Azizi [Yazd University, Yazd (Iran, Islamic Republic of); Rahmani, Farzad [Kar Higher Education Institute, Qazvin (Iran, Islamic Republic of)

    2014-11-15

    A free bulge test and ductile fracture criteria were used to obtain the forming limit diagrams (FLD) of aluminum alloy AA6063 tubes at high temperatures. Ductile fracture criteria were calibrated using the results of uniaxial tension tests at various elevated temperatures and different strain rates through adjusting the Zener-Holloman parameter. High temperature free bulge test of tubes was simulated in finite element software Abaqus, and tube bursting was predicted using ductile fracture criteria under different loading paths. FLDs which were obtained from finite element simulation were compared to experimental results to select the most accurate criterion for prediction of forming limit diagram. According to the results, all studied ductile fracture criteria predict similarly when forming condition is close to the uniaxial tension, while Ayada criterion predicts the FLD at 473 K and 573 K very well.

  12. Application of DIC techniques to detect onset of necking and fracture in uniaxial and bulge tests

    Science.gov (United States)

    Stoughton, TB; Min, JY; Carsley, JE

    2017-09-01

    This document provides information on and instructions for detecting the onset of necking in conventional uniaxial tension tests and biaxial bulge tests, using DIC technology and analysis methods developed at General Motors. The analysis enables reduction of the number and the costs of tests required in conventional FLD determinations using Marciniak and Nakajima tooling, while also avoiding the most serious process-dependent effects associated with the latter tests. It also provides a cost effective approach to develop forming limits for anisotropic sheet materials. In addition to providing this new experimental technique, the document will review the new procedures developed at General Motors for analysis of FLD tests and bulge tests to obtain reliable input for complete material card descriptions of advanced constitutive and forming limit models.

  13. New VVV Survey Globular Cluster Candidates in the Milky Way Bulge

    Energy Technology Data Exchange (ETDEWEB)

    Minniti, Dante; Gómez, Matías [Departamento de Física, Facultad de Ciencias Exactas, Universidad Andrés Bello, Av. Fernandez Concha 700, Las Condes, Santiago (Chile); Geisler, Douglas; Fernández-Trincado, Jose G. [Departamento de Astronomía, Casilla 160-C, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Alonso-García, Javier; Beamín, Juan Carlos; Borissova, Jura; Catelan, Marcio; Ramos, Rodrigo Contreras; Kurtev, Radostin; Pullen, Joyce [Instituto Milenio de Astrofísica, Santiago (Chile); Palma, Tali; Clariá, Juan J. [Observatorio Astronómico, Universidad Nacional de Córdoba, Laprida 854, Córdoba (Argentina); Cohen, Roger E. [Space Telescope Science Institute, 2700 San Martin Drive, Baltimore (United States); Dias, Bruno [European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago (Chile); Hempel, Maren [Pontificia Universidad Católica de Chile, Instituto de Astrofísica, Av. Vicuña Mackenna 4860, Santiago (Chile); Ivanov, Valentin D. [European Southern Observatory, Karl-Schwarszchild-Str. 2, D-85748 Garching bei Muenchen (Germany); Lucas, Phillip W. [Dept. of Astronomy, University of Hertfordshire, Hertfordshire (United Kingdom); Moni-Bidin, Christian; Alegría, Sebastian Ramírez [Instituto de Astronomía, Universidad Católica del Norte, Antofagasta (Chile); and others

    2017-11-10

    It is likely that a number of Galactic globular clusters remain to be discovered, especially toward the Galactic bulge. High stellar density combined with high and differential interstellar reddening are the two major problems for finding globular clusters located toward the bulge. We use the deep near-IR photometry of the VISTA Variables in the Vía Láctea (VVV) Survey to search for globular clusters projected toward the Galactic bulge, and hereby report the discovery of 22 new candidate globular clusters. These objects, detected as high density regions in our maps of bulge red giants, are confirmed as globular cluster candidates by their color–magnitude diagrams. We provide their coordinates as well as their near-IR color–magnitude diagrams, from which some basic parameters are derived, such as reddenings and heliocentric distances. The color–magnitude diagrams reveal well defined red giant branches in all cases, often including a prominent red clump. The new globular cluster candidates exhibit a variety of extinctions (0.06 < A {sub Ks} < 2.77) and distances (5.3 < D < 9.5 kpc). We also classify the globular cluster candidates into 10 metal-poor and 12 metal-rich clusters, based on the comparison of their color–magnitude diagrams with those of known globular clusters also observed by the VVV Survey. Finally, we argue that the census for Galactic globular clusters still remains incomplete, and that many more candidate globular clusters (particularly the low luminosity ones) await to be found and studied in detail in the central regions of the Milky Way.

  14. Quasi-periodic oscillations in bright galactic-bulge X-ray sources

    Science.gov (United States)

    Lamb, F. K.; Shibazaki, N.; Alpar, M. A.; Shaham, J.

    1985-01-01

    Quasiperiodic oscillations with frequencies in the range 5-50 Hz have recently been discovered in X-rays from two bright galactic-bulge sources and Sco X-1. These sources are weakly magnetic neutron stars accreting from disks in which the plasma is clumped. The interaction of the magnetosphere with clumps in the inner disk causes oscillations in the X-ray flux with many of the properties observed.

  15. Quasi-periodic oscillations in bright galactic-bulge X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, F.K.; Shibazaki, N.; Alpar, M.A.; Shaham, J.

    1985-10-24

    Quasi-periodic oscillations with frequencies in the range 5-50 Hz have recently been discovered in X-rays from two bright galactic-bulge sources and ScoX-1. It is proposed that these sources are weakly magnetic neutron stars accreting from disks in which the plasma is clumped. The interaction of the magnetosphere with clumps in the inner disk modulates the accretion rate, causing oscillations in the X-ray flux with many of the observed properties.

  16. Quasiperiodic oscillations in bright galactic-bulge x-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, F.K.; Shibazaki, N.; Alpar, M.A.; Shaham, J.

    1985-09-01

    Quasiperiodic oscillations with frequencies in the range 5-50 Hz have recently been discovered in x-rays from two bright galactic-bulge sources and Sco X-1. These sources are weakly magnetic neutron stars accreting from disks in which the plasma is clumped. The interaction of the magnetosphere with clumps in the inner disk causes oscillations in the x-ray flux with many of the properties observed.

  17. Quasiperiodic oscillations in bright galactic-bulge X-ray sources

    Science.gov (United States)

    Lamb, F. K.; Shibazaki, N.; Alpar, M. A.; Shaham, J.

    1985-01-01

    Quasiperiodic oscillations with frequencies in the range 5-50 Hz have recently been discovered in X-rays from two bright galactic-bulge sources and Sco X-1. These sources are weakly magnetic neutron stars accreting from disks which the plasma is clumped. The interaction of the magnetosphere with clumps in the inner disk causes oscillations in the X-ray flux with many of the properties observed.

  18. An Optimal Strategy for Accurate Bulge-to-disk Decomposition of Disk Galaxies

    Science.gov (United States)

    Gao, Hua; Ho, Luis C.

    2017-08-01

    The development of two-dimensional (2D) bulge-to-disk decomposition techniques has shown their advantages over traditional one-dimensional (1D) techniques, especially for galaxies with non-axisymmetric features. However, the full potential of 2D techniques has yet to be fully exploited. Secondary morphological features in nearby disk galaxies, such as bars, lenses, rings, disk breaks, and spiral arms, are seldom accounted for in 2D image decompositions, even though some image-fitting codes, such as GALFIT, are capable of handling them. We present detailed, 2D multi-model and multi-component decomposition of high-quality R-band images of a representative sample of nearby disk galaxies selected from the Carnegie-Irvine Galaxy Survey, using the latest version of GALFIT. The sample consists of five barred and five unbarred galaxies, spanning Hubble types from S0 to Sc. Traditional 1D decomposition is also presented for comparison. In detailed case studies of the 10 galaxies, we successfully model the secondary morphological features. Through a comparison of best-fit parameters obtained from different input surface brightness models, we identify morphological features that significantly impact bulge measurements. We show that nuclear and inner lenses/rings and disk breaks must be properly taken into account to obtain accurate bulge parameters, whereas outer lenses/rings and spiral arms have a negligible effect. We provide an optimal strategy to measure bulge parameters of typical disk galaxies, as well as prescriptions to estimate realistic uncertainties of them, which will benefit subsequent decomposition of a larger galaxy sample.

  19. Pulsating variable stars in the MACHO bulge database: the semiregular variables

    Energy Technology Data Exchange (ETDEWEB)

    Minniti, D.; Alcock, C.; Allsman, R.A. [and others

    1997-11-01

    We review the pulsating stars contained in the top 24 fields of the MACHO bulge database, with special emphasis on the red semireg-ular stars. Based on period, amplitude and color cuts, we have selected a sample of 2000 semireguku variables with 15 < P < 100 days. Their period-luminosity relation is studied, as well ss their spatial distribution. We find that they follow the bar, unlike the RR Lyrae in these fields.

  20. An Optimal Strategy for Accurate Bulge-to-disk Decomposition of Disk Galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Gao Hua [Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)

    2017-08-20

    The development of two-dimensional (2D) bulge-to-disk decomposition techniques has shown their advantages over traditional one-dimensional (1D) techniques, especially for galaxies with non-axisymmetric features. However, the full potential of 2D techniques has yet to be fully exploited. Secondary morphological features in nearby disk galaxies, such as bars, lenses, rings, disk breaks, and spiral arms, are seldom accounted for in 2D image decompositions, even though some image-fitting codes, such as GALFIT, are capable of handling them. We present detailed, 2D multi-model and multi-component decomposition of high-quality R -band images of a representative sample of nearby disk galaxies selected from the Carnegie-Irvine Galaxy Survey, using the latest version of GALFIT. The sample consists of five barred and five unbarred galaxies, spanning Hubble types from S0 to Sc. Traditional 1D decomposition is also presented for comparison. In detailed case studies of the 10 galaxies, we successfully model the secondary morphological features. Through a comparison of best-fit parameters obtained from different input surface brightness models, we identify morphological features that significantly impact bulge measurements. We show that nuclear and inner lenses/rings and disk breaks must be properly taken into account to obtain accurate bulge parameters, whereas outer lenses/rings and spiral arms have a negligible effect. We provide an optimal strategy to measure bulge parameters of typical disk galaxies, as well as prescriptions to estimate realistic uncertainties of them, which will benefit subsequent decomposition of a larger galaxy sample.

  1. Stellar Sources in the ISOGAL Inner Galactic Bulge Field D. Κ. Ojha1 ...

    Indian Academy of Sciences (India)

    tribpo

    Received 2000 March 27; accepted 2000 May 11. Abstract. ISOGAL is a survey at 7 and 15 µm with ISOCAM of the inner galactic disk and bulge of our Galaxy. The survey covers ~ 22 deg2 in selected areas of the central l = ±30 degree of the inner Galaxy. In this paper, we report the study of a small ISOGAL field in the inner ...

  2. Bulges and discs in the local Universe. Linking the galaxy structure to star formation activity

    Science.gov (United States)

    Morselli, L.; Popesso, P.; Erfanianfar, G.; Concas, A.

    2017-01-01

    We use a sample built on the SDSS DR7 catalogue and the bulge-disc decomposition of Simard et al. (2011, ApJS, 196, 11) to study how the bulge and disc components contribute to the parent galaxy's star formation activity, by determining its position in the star formation rate (SFR) - stellar mass (M⋆) plane at 0.02 age or metallicity content, suggesting different evolutionary paths for bulges on the MS and green valley with respect to those in the quiescence region. The disc g-r colour anti-correlates at any mass with the distance from the MS, getting redder when approaching the MS lower envelope and the quiescence region. The anti-correlation flattens as a function of the stellar mass, likely due to a higher level of dust obscuration in massive SF galaxies. We conclude that the position of a galaxy in the Log SFR - Log M⋆ plane depends on the star formation activity of its components: above the MS both bulge and disc are actively star forming. The nuclear activity is the first to be suppressed, moving the galaxies on the MS. Once the disc stops forming stars as well, the galaxy moves below the MS and eventually to the quiescence region. This is confirmed by a significant percentage ( 45%) of passive galaxies with a secure two component morphology, coexisting with a population of pure spheroidals. Our findings are qualitatively in agreement with the compaction-depletion scenario, in which subsequent phases of gas inflow in the centre of a galaxy and depletion due to high star formation activity move the galaxy across the MS before the final quenching episode takes place.

  3. 3 CFR 8465 - Proclamation 8465 of December 15, 2009. 65th Anniversary of the Battle of the Bulge, 2009

    Science.gov (United States)

    2010-01-01

    ... Americans. Like patriots before them, they stood resolute, confident in their training, and determined to... Bulge continues in Iraq, Afghanistan, and wherever our men and women in uniform are serving. They...

  4. Brightness variations of the northern 630nm intertropical arc and the midnight pressure bulge over Eritrea

    Directory of Open Access Journals (Sweden)

    R. H. Wiens

    2004-09-01

    Full Text Available The nightglow brightness at 630nm from the thermospheric O(1D layer was monitored nightly at Asmara, Eritrea (15.4° N, 39.9° E, 7° N dip with an all-sky imager. Averages of north-south strips of the images enabled contour plots of brightness on a latitude vs. local time grid. The contours show the movement of the intertropical arc southward before midnight, staying just north of Asmara after midnight, and gradually brightening to a maximum at 02:00h local civil time, 02:00 LT, after which it disappears before dawn. It is argued that all features of the plots can be explained by known mechanisms capable of driving ions along magnetic field lines, including the fountain effect, summer to winter transequatorial winds, and the midnight pressure bulge. The 02:00 LT brightness maximum is the most striking and the most persistent feature in the data. The persistence of the location of the 02:00 LT brightening is attributed to a pressure bulge centered on the geographic equator at midnight and extending to higher latitudes with increasing local time in both the winter and the summer hemispheres. The bulge is shown to be stronger near solstice than near equinox, confirming earlier work.

  5. Brightness variations of the northern 630nm intertropical arc and the midnight pressure bulge over Eritrea

    Directory of Open Access Journals (Sweden)

    R. H. Wiens

    2004-09-01

    Full Text Available The nightglow brightness at 630nm from the thermospheric O(1D layer was monitored nightly at Asmara, Eritrea (15.4° N, 39.9° E, 7° N dip with an all-sky imager. Averages of north-south strips of the images enabled contour plots of brightness on a latitude vs. local time grid. The contours show the movement of the intertropical arc southward before midnight, staying just north of Asmara after midnight, and gradually brightening to a maximum at 02:00h local civil time, 02:00 LT, after which it disappears before dawn. It is argued that all features of the plots can be explained by known mechanisms capable of driving ions along magnetic field lines, including the fountain effect, summer to winter transequatorial winds, and the midnight pressure bulge.

    The 02:00 LT brightness maximum is the most striking and the most persistent feature in the data. The persistence of the location of the 02:00 LT brightening is attributed to a pressure bulge centered on the geographic equator at midnight and extending to higher latitudes with increasing local time in both the winter and the summer hemispheres. The bulge is shown to be stronger near solstice than near equinox, confirming earlier work.

  6. The INTEGRAL Galactic bulge monitoring program: the first 1.5 years

    DEFF Research Database (Denmark)

    Kuulkers, E.; Shaw, S.E.; Paizis, A.

    2007-01-01

    Aims. The Galactic bulge region is a rich host of variable high-energy point sources. Since 2005, February 17 we are monitoring the source activity in the Galactic bulge region regularly and frequently, i.e., about every three days, with the instruments onboard INTEGRAL. Thanks to the large field...... of view, the imaging capabilities and the sensitivity at hard X-rays, we are able to present for the first time a detailed homogeneous (hard) X-ray view of a sample of 76 sources in the Galactic bulge region. Methods. We describe the successful monitoring program and show the first results from the start......-2901b, IGR J17536-2339, and IGR J17541-2252. We report here on some of the high-energy properties of these sources. Conclusions. The high-energy light curves of all the sources in the field of view, and the high-energy images of the region, are made available through the WWW, as soon as possible after...

  7. Thermodynamic Study of Tl6SBr4 Compound and Some Regularities in Thermodynamic Properties of Thallium Chalcohalides

    Directory of Open Access Journals (Sweden)

    Dunya Mahammad Babanly

    2017-01-01

    Full Text Available The solid-phase diagram of the Tl-TlBr-S system was clarified and the fundamental thermodynamic properties of Tl6SBr4 compound were studied on the basis of electromotive force (EMF measurements of concentration cells relative to a thallium electrode. The EMF results were used to calculate the relative partial thermodynamic functions of thallium in alloys and the standard integral thermodynamic functions (-ΔfG0, -ΔfH0, and S0298 of Tl6SBr4 compound. All data regarding thermodynamic properties of thallium chalcogen-halides are generalized and comparatively analyzed. Consequently, certain regularities between thermodynamic functions of thallium chalcogen-halides and their binary constituents as well as degree of ionization (DI of chemical bonding were revealed.

  8. Galactic Bulge Giants: Probing Stellar and Galactic Evolution. 1. Catalogue of Spitzer IRAC and MIPS Sources (PREPRINT)

    Science.gov (United States)

    2010-12-29

    Athens, Greece 4 Dipartimento di Fisica Generale ”A. Avogadro”, Universita degli Studi di Torino, Via Pietro Giuria 1, 10125 Torino, Italy 5...We aim at providing evidence and answers to these questions. Methods. To this end, we observed seven 15 × 15 arcmin2 fields in the nuclear bulge and...fields in the nuclear bulge and its vicinity with unprecedented sensitivity using the IRAC and MIPS imaging instruments on-board the Spitzer Space

  9. Stem cells in the hair follicle bulge contribute to wound repair but not to homeostasis of the epidermis.

    Science.gov (United States)

    Ito, Mayumi; Liu, Yaping; Yang, Zaixin; Nguyen, Jane; Liang, Fan; Morris, Rebecca J; Cotsarelis, George

    2005-12-01

    The discovery of long-lived epithelial stem cells in the bulge region of the hair follicle led to the hypothesis that epidermal renewal and epidermal repair after wounding both depend on these cells. To determine whether bulge cells are necessary for epidermal renewal, here we have ablated these cells by targeting them with a suicide gene encoding herpes simplex virus thymidine kinase (HSV-TK) using a Keratin 1-15 (Krt1-15) promoter. We show that ablation leads to complete loss of hair follicles but survival of the epidermis. Through fate-mapping experiments, we find that stem cells in the hair follicle bulge do not normally contribute cells to the epidermis which is organized into epidermal proliferative units, as previously predicted. After epidermal injury, however, cells from the bulge are recruited into the epidermis and migrate in a linear manner toward the center of the wound, ultimately forming a marked radial pattern. Notably, although the bulge-derived cells acquire an epidermal phenotype, most are eliminated from the epidermis over several weeks, indicating that bulge stem cells respond rapidly to epidermal wounding by generating short-lived 'transient amplifying' cells responsible for acute wound repair. Our findings have implications for both gene therapy and developing treatments for wounds because it will be necessary to consider epidermal and hair follicle stem cells as distinct populations.

  10. Thermodynamics of Crystalline States

    CERN Document Server

    Fujimoto, Minoru

    2010-01-01

    Thermodynamics is a well-established discipline of physics for properties of matter in thermal equilibrium surroundings. Applying to crystals, however, the laws encounter undefined properties of crystal lattices, which therefore need to be determined for a clear and well-defined description of crystalline states. Thermodynamics of Crystalline States explores the roles played by order variables and dynamic lattices in crystals in a wholly new way. This book is divided into three parts. The book begins by clarifying basic concepts for stable crystals. Next, binary phase transitions are discussed to study collective motion of order variables, as described mostly as classical phenomena. In the third part, the multi-electron system is discussed theoretically, as a quantum-mechanical example, for the superconducting state in metallic crystals. Throughout the book, the role played by the lattice is emphasized and examined in-depth. Thermodynamics of Crystalline States is an introductory treatise and textbook on meso...

  11. Statistical thermodynamics of alloys

    CERN Document Server

    Gokcen, N A

    1986-01-01

    This book is intended for scientists, researchers, and graduate students interested in solutions in general, and solutions of metals in particular. Readers are assumed to have a good background in thermodynamics, presented in such books as those cited at the end of Chapter 1, "Thermo­ dynamic Background." The contents of the book are limited to the solutions of metals + metals, and metals + metalloids, but the results are also appli­ cable to numerous other types of solutions encountered by metallurgists, materials scientists, geologists, ceramists, and chemists. Attempts have been made to cover each topic in depth with numerical examples whenever necessary. Chapter 2 presents phase equilibria and phase diagrams as related to the thermodynamics of solutions. The emphasis is on the binary diagrams since the ternary diagrams can be understood in terms of the binary diagrams coupled with the phase rule, and the Gibbs energies of mixing. The cal­ culation of thermodynamic properties from the phase diagrams is ...

  12. Extended Irreversible Thermodynamics

    CERN Document Server

    Jou, David

    2010-01-01

    This is the 4th edition of the highly acclaimed monograph on Extended Irreversible Thermodynamics, a theory that goes beyond the classical theory of irreversible processes. In contrast to the classical approach, the basic variables describing the system are complemented by non-equilibrium quantities. The claims made for extended thermodynamics are confirmed by the kinetic theory of gases and statistical mechanics. The book covers a wide spectrum of applications, and also contains a thorough discussion of the foundations and the scope of the current theories on non-equilibrium thermodynamics. For this new edition, the authors critically revised existing material while taking into account the most recent developments in fast moving fields such as heat transport in micro- and nanosystems or fast solidification fronts in materials sciences. Several fundamental chapters have been revisited emphasizing physics and applications over mathematical derivations. Also, fundamental questions on the definition of non-equil...

  13. METALLICITY DISTRIBUTION FUNCTIONS, RADIAL VELOCITIES, AND ALPHA ELEMENT ABUNDANCES IN THREE OFF-AXIS BULGE FIELDS

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Christian I.; Rich, R. Michael [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States); Kobayashi, Chiaki [Centre for Astrophysics Research, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Kunder, Andrea; De Propris, Roberto [Cerro Tololo Inter-American Observatory, Casilla 603, La Serena (Chile); Pilachowski, Catherine A. [Department of Astronomy, Indiana University, Swain West 319, 727 East Third Street, Bloomington, IN 47405-7105 (United States); Koch, Andreas, E-mail: cijohnson@astro.ucla.edu, E-mail: rmr@astro.ucla.edu, E-mail: c.kobayashi@herts.ac.uk, E-mail: akunder@ctio.noao.edu, E-mail: catyp@astro.indiana.edu, E-mail: akoch@lsw.uni-heidelberg.de [Zentrum fuer Astronomie der Universitaet Heidelberg, Landessternwarte, Koenigstuhl 12, Heidelberg (Germany)

    2013-03-10

    We present radial velocities and chemical abundance ratios of [Fe/H], [O/Fe], [Si/Fe], and [Ca/Fe] for 264 red giant branch stars in three Galactic bulge off-axis fields located near (l, b) = (-5.5, -7), (-4, -9), and (+8.5, +9). The results are based on equivalent width and spectrum synthesis analyses of moderate resolution (R Almost-Equal-To 18,000), high signal-to-noise ratio (S/N {approx} 75-300 pixel{sup -1}) spectra obtained with the Hydra spectrographs on the Blanco 4 m and WIYN 3.5 m telescopes. The targets were selected from the blue side of the giant branch to avoid cool stars that would be strongly affected by CN and TiO; however, a comparison of the color-metallicity distribution in literature samples suggests that our selection of bluer targets should not present a significant bias against metal-rich stars. We find a full range in metallicity that spans [Fe/H] Almost-Equal-To -1.5 to +0.5, and that, in accordance with the previously observed minor-axis vertical metallicity gradient, the median [Fe/H] also declines with increasing Galactic latitude in off-axis fields. The off-axis vertical [Fe/H] gradient in the southern bulge is estimated to be {approx}0.4 dex kpc{sup -1}; however, comparison with the minor-axis data suggests that a strong radial gradient does not exist. The (+8.5, +9) field exhibits a higher than expected metallicity, with a median [Fe/H] = -0.23, that might be related to a stronger presence of the X-shaped bulge structure along that line-of-sight. This could also be the cause of an anomalous increase in the median radial velocity for intermediate metallicity stars in the (+8.5, +9) field. However, the overall radial velocity and dispersion for each field are in good agreement with recent surveys and bulge models. All fields exhibit an identical, strong decrease in velocity dispersion with increasing metallicity that is consistent with observations in similar minor-axis outer bulge fields. Additionally, the [O/Fe], [Si/Fe], and [Ca

  14. Thermodynamics II essentials

    CERN Document Server

    REA, The Editors of

    2013-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Thermodynamics II includes review of thermodynamic relations, power and refrigeration cycles, mixtures and solutions, chemical reactions, chemical equilibrium, and flow through nozzl

  15. Thermodynamics for engineers

    CERN Document Server

    Wong, Kaufui Vincent

    2011-01-01

    Praise for the First Edition from Students: "It is a great thermodynamics text…I loved it!-Mathew Walters "The book is comprehensive and easy to understand. I love the real world examples and problems, they make you feel like you are learning something very practical."-Craig Paxton"I would recommend the book to friends."-Faure J. Malo-Molina"The clear diction, as well as informative illustrations and diagrams, help convey the material clearly to the reader."-Paul C. Start"An inspiring and effective tool for any aspiring scientist or engineer. Definitely the best book on Classical Thermodynamics out."-Seth Marini.

  16. Concise chemical thermodynamics

    CERN Document Server

    Peters, APH

    2010-01-01

    EnergyThe Realm of ThermodynamicsEnergy BookkeepingNature's Driving ForcesSetting the Scene: Basic IdeasSystem and SurroundingsFunctions of StateMechanical Work and Expanding GasesThe Absolute Temperature Scale Forms of Energy and Their Interconversion Forms of Renewable Energy Solar Energy Wind Energy Hydroelectric Power Geothermal Energy Biomass Energy References ProblemsThe First Law of Thermodynamics Statement of the First Law Reversible Expansion of an Ideal GasConstant-Volume ProcessesConstant-Pressure ProcessesA New Function: EnthalpyRelationship between ?H and ?UUses and Conventions of

  17. Mechanics, Waves and Thermodynamics

    Science.gov (United States)

    Ranjan Jain, Sudhir

    2016-05-01

    Figures; Preface; Acknowledgement; 1. Energy, mass, momentum; 2. Kinematics, Newton's laws of motion; 3. Circular motion; 4. The principle of least action; 5. Work and energy; 6. Mechanics of a system of particles; 7. Friction; 8. Impulse and collisions; 9. Central forces; 10. Dimensional analysis; 11. Oscillations; 12. Waves; 13. Sound of music; 14. Fluid mechanics; 15. Water waves; 16. The kinetic theory of gases; 17. Concepts and laws of thermodynamics; 18. Some applications of thermodynamics; 19. Basic ideas of statistical mechanics; Bibliography; Index.

  18. Beyond Equilibrium Thermodynamics

    Science.gov (United States)

    Öttinger, Hans Christian

    2005-01-01

    Beyond Equilibrium Thermodynamics fills a niche in the market by providing a comprehensive introduction to a new, emerging topic in the field. The importance of non-equilibrium thermodynamics is addressed in order to fully understand how a system works, whether it is in a biological system like the brain or a system that develops plastic. In order to fully grasp the subject, the book clearly explains the physical concepts and mathematics involved, as well as presenting problems and solutions; over 200 exercises and answers are included. Engineers, scientists, and applied mathematicians can all use the book to address their problems in modelling, calculating, and understanding dynamic responses of materials.

  19. Choice & Consequence

    DEFF Research Database (Denmark)

    Khan, Azam

    To move toward environmental sustainability, we propose that a computational approach may be needed due to the complexity of resource production and consumption. While digital sensors and predictive simulation has the potential to help us to minimize resource consumption, the indirect relation...... between cause and effect in complex systems complicates decision making. To address this issue, we examine the central role that data-driven decision making could play in critical domains such as sustainability or medical treatment. We developed systems for exploratory data analysis and data visualization...... of data analysis and instructional interface design, to both simulation systems and decision support interfaces. We hope that projects such as these will help people to understand the link between their choices and the consequences of their decisions....

  20. Experimental thermodynamics experimental thermodynamics of non-reacting fluids

    CERN Document Server

    Neindre, B Le

    2013-01-01

    Experimental Thermodynamics, Volume II: Experimental Thermodynamics of Non-reacting Fluids focuses on experimental methods and procedures in the study of thermophysical properties of fluids. The selection first offers information on methods used in measuring thermodynamic properties and tests, including physical quantities and symbols for physical quantities, thermodynamic definitions, and definition of activities and related quantities. The text also describes reference materials for thermometric fixed points, temperature measurement under pressures, and pressure measurements. The publicatio

  1. Thermodynamic disequilibrium as a biomarker in Mars

    Science.gov (United States)

    Delgado-Bonal, A.; Simoncini, E.; Martín-Torres, F. J.

    2012-04-01

    Disequilibrium should be a necessary condition in planetary body atmospheres hosting life, as a consequence of the chemical interchange between the atmosphere and the living organisms. In this study, we analyze the thermodynamics of Mars atmosphere considering more than 50 reactions (including those involving traditionally considered biomarkers such as H2O or CH4), and estimating their entropy production and Gibbs free energy. Those complementary measurements provide information on the disequilibrium of the atmosphere in a measurable way. Besides the atmosphere's thermodynamic state, the interaction between surface-atmosphere has been analyzed considering the abiotic analogs of those sources of energy for life on Earth (for example iron oxidation). Using thermodynamic criteria we have studied the habitability under two different situations in Mars: the surface of the Gale crater (4.6S 137.2E),where the Mars Science Laboratory will land in August 2012, and a hypothetical cave near the equatorial zone. The study of the time-dependence of these thermodynamic quantities provides us with a complete tool to study the past and present habitability in Mars.

  2. A New Thermodynamics from Nuclei to Stars

    Directory of Open Access Journals (Sweden)

    Dieter H.E. Gross

    2004-03-01

    Full Text Available Abstract: Equilibrium statistics of Hamiltonian systems is correctly described by the microcanonical ensemble. Classically this is the manifold of all points in the N-body phase space with the given total energy. Due to Boltzmann's principle, eS=tr(δ(E-H, its geometrical size is related to the entropy S(E,N,.... This definition does not invoke any information theory, no thermodynamic limit, no extensivity, and no homogeneity assumption, as are needed in conventional (canonical thermo-statistics. Therefore, it describes the equilibrium statistics of extensive as well of non-extensive systems. Due to this fact it is the fundamental definition of any classical equilibrium statistics. It can address nuclei and astrophysical objects as well. All kind of phase transitions can be distinguished sharply and uniquely for even small systems. It is further shown that the second law is a natural consequence of the statistical nature of thermodynamics which describes all systems with the same -- redundant -- set of few control parameters simultaneously. It has nothing to do with the thermodynamic limit. It even works in systems which are by far than any thermodynamic "limit".

  3. The Thermodynamics of Black Holes

    National Research Council Canada - National Science Library

    Emparan, Roberto; Tinto, Massimo; Barbero G, J Fernando; Heusler, Markus; Rendall, Alan D; Adamo, Timothy M; Liebling, Steven L; Sasaki, Misao; Poisson, Eric; Wald, Robert M; Postnov, Konstantin A; Amendola, Luca; Shibata, Masaru; Tagoshi, Hideyuki; Reall, Harvey S; Kozameh, Carlos; Palenzuela, Carlos; Yungelson, Lev R; Villaseñor, Eduardo J. S; Appleby, Stephen; Taniguchi, Keisuke; Dhurandhar, Sanjeev V; Bacon, David; Newman, Ezra T; Baker, Tessa; Baldi, Marco; Bartolo, Nicola; Blanchard, Alain; Bonvin, Camille; Borgani, Stefano; Branchini, Enzo; Burrage, Clare; Camera, Stefano; Carbone, Carmelita; Casarini, Luciano; Cropper, Mark; de Rham, Claudia; Di Porto, Cinzia; Ealet, Anne; Ferreira, Pedro G; Finelli, Fabio; García-Bellido, Juan; Giannantonio, Tommaso; Guzzo, Luigi; Heavens, Alan; Heisenberg, Lavinia; Heymans, Catherine; Hoekstra, Henk; Hollenstein, Lukas; Holmes, Rory; Horst, Ole; Jahnke, Knud; Kitching, Thomas D; Koivisto, Tomi; Kunz, Martin; La Vacca, Giuseppe; March, Marisa; Majerotto, Elisabetta; Markovic, Katarina; Marsh, David; Marulli, Federico; Massey, Richard; Mellier, Yannick; Mota, David F; Nunes, Nelson J; Percival, Will; Pettorino, Valeria; Porciani, Cristiano; Quercellini, Claudia; Read, Justin; Rinaldi, Massimiliano; Sapone, Domenico; Scaramella, Roberto; Skordis, Constantinos; Simpson, Fergus; Taylor, Andy; Thomas, Shaun; Trotta, Roberto; Verde, Licia; Vernizzi, Filippo; Vollmer, Adrian; Wang, Yun; Weller, Jochen; Zlosnik, Tom

    ...We review the present status of black hole thermodynamics. Our review includes discussion of classical black hole thermodynamics, Hawking radiation from black holes, the generalized second law, and the issue of entropy bounds...

  4. Chemical thermodynamics. An introduction

    Energy Technology Data Exchange (ETDEWEB)

    Keszei, Ernoe [Budapest Univ. (Hungary). Dept. of Physical Chemistry

    2012-07-01

    Eminently suitable as a required textbook comprising complete material for or an undergraduate chemistry major course in chemical thermodynamics. Clearly explains details of formal derivations that students can easily follow and so master applied mathematical operations. Offers problems and solutions at the end of each chapter for self-test and self- or group study. This course-derived undergraduate textbook provides a concise explanation of the key concepts and calculations of chemical thermodynamics. Instead of the usual 'classical' introduction, this text adopts a straightforward postulatory approach that introduces thermodynamic potentials such as entropy and energy more directly and transparently. Structured around several features to assist students' understanding, Chemical Thermodynamics: - Develops applications and methods for the ready treatment of equilibria on a sound quantitative basis. - Requires minimal background in calculus to understand the text and presents formal derivations to the student in a detailed but understandable way. - Offers end-of-chapter problems (and answers) for self-testing and review and reinforcement, of use for self- or group study. This book is suitable as essential reading for courses in a bachelor and master chemistry program and is also valuable as a reference or textbook for students of physics, biochemistry and materials science.

  5. Thermodynamics with Design Problems.

    Science.gov (United States)

    Cilento, E. V.; Sears, J. T.

    1983-01-01

    Discusses how basic thermodynamics concepts are integrated with design problems. Includes course goals, instructional strategies, and major advantages/disadvantages of the integrated design approach. Advantages include making subject more concrete, emphasizing interrelation of variables, and reinforcing concepts by use in design analysis; whereas…

  6. Thermodynamics of meat proteins

    NARCIS (Netherlands)

    Sman, van der R.G.M.

    2012-01-01

    We describe the water activity of meat, being a mixture of proteins, salts and water, by the Free-Volume-Flory–Huggins (FVFH) theory augmented with the equation. Earlier, the FVFH theory is successfully applied to describe the thermodynamics to glucose homopolymers like starch, dextrans and

  7. Thermodynamics and statistical mechanics

    CERN Document Server

    Landsberg, Peter T

    1990-01-01

    Exceptionally articulate treatment combines precise mathematical style with strong physical intuition. Wide range of applications includes negative temperatures, negative heat capacities, special and general relativistic effects, black hole thermodynamics, gravitational collapse, more. Over 100 problems with worked solutions. Advanced undergraduate, graduate level. Table of applications. Useful formulas and other data.

  8. Nonequilibrium thermodynamics of nucleation

    NARCIS (Netherlands)

    Schweizer, M.; Sagis, L.M.C.

    2014-01-01

    We present a novel approach to nucleation processes based on the GENERIC framework (general equation for the nonequilibrium reversible-irreversible coupling). Solely based on the GENERIC structure of time-evolution equations and thermodynamic consistency arguments of exchange processes between a

  9. Thermodynamic stabilization of colloids

    NARCIS (Netherlands)

    Stol, R.J.; Bruyn, P.L. de

    An analysis is given of the conditions necessary for obtaining a thermodynamically stable dispersion (TSD) of solid particles in a continuous aqueous solution phase. The role of the adsorption of potential-determining ions at the planar interface in lowering the interfacial free energy (γ) to

  10. The thermodynamics of portfolios

    OpenAIRE

    Piotrowski, Edward W.; Jan Sladkowski

    2000-01-01

    We propose a new method of valuation of portfolios and their respective investing strategies. To this end we define a canonical ensemble of portfolios that allows to use the formalism of thermodynamics. (final version published in Acta Phys.Pol.B,32(2001)597-604)

  11. On Teaching Thermodynamics

    Science.gov (United States)

    Debbasch, F.

    2011-01-01

    The logical structure of classical thermodynamics is presented in a modern, geometrical manner. The first and second law receive clear, operatively oriented statements and the Gibbs free energy extremum principle is fully discussed. Applications relevant to chemistry, such as phase transitions, dilute solutions theory and, in particular, the law…

  12. Thermodynamical Arguments against Evolution

    Science.gov (United States)

    Rosenhouse, Jason

    2017-01-01

    The argument that the second law of thermodynamics contradicts the theory of evolution has recently been revived by anti-evolutionists. In its basic form, the argument asserts that whereas evolution implies that there has been an increase in biological complexity over time, the second law, a fundamental principle of physics, shows this to be…

  13. Thermodynamics Far from the Thermodynamic Limit.

    Science.gov (United States)

    de Miguel, Rodrigo; Rubí, J Miguel

    2017-11-16

    Understanding how small systems exchange energy with a heat bath is important to describe how their unique properties can be affected by the environment. In this contribution, we apply Landsberg's theory of temperature-dependent energy levels to describe the progressive thermalization of small systems as their spectrum is perturbed by a heat bath. We propose a mechanism whereby the small system undergoes a discrete series of excitations and isentropic spectrum adjustments leading to a final state of thermal equilibrium. This produces standard thermodynamic results without invoking system size. The thermal relaxation of a single harmonic oscillator is analyzed as a model example of a system with a quantized spectrum than can be embedded in a thermal environment. A description of how the thermal environment affects the spectrum of a small system can be the first step in using environmental factors, such as temperature, as parameters in the design and operation of nanosystem properties.

  14. Thermodynamics for the practicing engineer

    CERN Document Server

    Theodore, Louis; Vanvliet, Timothy

    2009-01-01

    This book concentrates specifically on the applications of thermodynamics, rather than the theory. It addresses both technical and pragmatic problems in the field, and covers such topics as enthalpy effects, equilibrium thermodynamics, non-ideal thermodynamics and energy conversion applications. Providing the reader with a working knowledge of the principles of thermodynamics, as well as experience in their application, it stands alone as an easy-to-follow self-teaching aid to practical applications and contains worked examples.

  15. Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia

    Energy Technology Data Exchange (ETDEWEB)

    Glavatskiy, K. S. [School of Chemical Engineering, The University of Queensland, St. Lucia QLD 4072 (Australia)

    2015-10-28

    Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called “mirror-image” systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval.

  16. Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia.

    Science.gov (United States)

    Glavatskiy, K S

    2015-10-28

    Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called "mirror-image" systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval.

  17. A parametric description of the 3D structure of the Galactic bar/bulge using the VVV survey

    Science.gov (United States)

    Simion, I. T.; Belokurov, V.; Irwin, M.; Koposov, S. E.; Gonzalez-Fernandez, C.; Robin, A. C.; Shen, J.; Li, Z.-Y.

    2017-11-01

    We study the structure of the inner Milky Way using the latest data release of the VISTA Variables in the Via Lactea (VVV) survey. The VVV is a deep near-infrared, multi-colour photometric survey with a coverage of 300 square degrees towards the bulge/bar. We use red clump (RC) stars to produce a high-resolution dust map of the VVV's field of view. From de-reddened colour-magnitude diagrams, we select red giant branch stars to investigate their 3D density distribution within the central 4 kpc. We demonstrate that our best-fitting parametric model of the bulge density provides a good description of the VVV data, with a median percentage residual of 5 per cent over the fitted region. The strongest of the otherwise low-level residuals are overdensities associated with a low-latitude structure as well as the so-called X-shape previously identified using the split RC. These additional components contribute only ˜5 per cent and ˜7 per cent respectively to the bulge mass budget. The best-fitting bulge is `boxy' with an axial ratio of [1:0.44:0.31] and is rotated with respect to the Sun-Galactic Centre line by at least 20°. We provide an estimate of the total, full sky, mass of the bulge of M_bulge^{Chabrier} = 2.36 × 10^{10} M_{⊙} for a Chabrier initial mass function. We show that there exists a strong degeneracy between the viewing angle and the dispersion of the RC absolute magnitude distribution. The value of the latter is strongly dependent on the assumptions made about the intrinsic luminosity function of the bulge.

  18. The consequences of "Culture's consequences"

    DEFF Research Database (Denmark)

    Knudsen, Fabienne; Froholdt, Lisa Loloma

    2009-01-01

    , but it may also have unintentional outcomes. It may lead to a deterministic view of other cultures, thereby reinforcing prejudices and underestimating other forms of differences; it risks blinding the participants of the specific context of a given communicative situation. The article opens with a critical...... review of the theory of Geert Hofstede, the most renowned representative of this theoretical approach. The practical consequences of using such a concept of culture is then analysed by means of a critical review of an article applying Hofstede to cross-cultural crews in seafaring. Finally, alternative...... views on culture are presented. The aim of the article is, rather than to promote any specific theory, to reflect about diverse perspectives of cultural sense-making in cross-cultural encounters. Udgivelsesdato: Oktober...

  19. Mapping the outer bulge with RRab stars from the VVV Survey

    Science.gov (United States)

    Gran, F.; Minniti, D.; Saito, R. K.; Zoccali, M.; Gonzalez, O. A.; Navarrete, C.; Catelan, M.; Contreras Ramos, R.; Elorrieta, F.; Eyheramendy, S.; Jordán, A.

    2016-07-01

    Context. The VISTA Variables in the Vía Láctea (VVV) is a near-IR time-domain survey of the Galactic bulge and southern plane. One of the main goals of this survey is to reveal the 3D structure of the Milky Way through their variable stars. In particular, enormous numbers of RR Lyrae stars have been discovered in the inner regions of the bulge (-8° ≲ b ≲ -1°) by optical surveys such as OGLE and MACHO, but leaving an unexplored window of more than ~47 sq deg (-10.0° ≲ ℓ ≲ + 10.7° and - 10.3° ≲ b ≲ -8.0°) observed by the VVV Survey. Aims: Our goal is to characterize the RR Lyrae stars in the outer bulge in terms of their periods, amplitudes, Fourier coefficients, and distances in order to evaluate the 3D structure of the bulge in this area. The distance distribution of RR Lyrae stars will be compared to that of red clump stars, which is known to trace a X-shaped structure, in order to determine whether these two different stellar populations share the same Galactic distribution. Methods: A search for RR Lyrae stars was performed in more than ~47 sq deg at low Galactic latitudes (-10.3° ≲ b ≲ -8.0°). In the procedure the χ2 value and analysis of variance (AoV) statistic methods were used to determine the variability and periodic features of the light curves, respectively. To prevent misclassifications, the analysis was performed only on the fundamental mode RR Lyrae stars (RRab) owing to similarities found in the near-IR light curve shapes of contact eclipsing binaries (W UMa) and first overtone RR Lyrae stars (RRc). On the other hand, the red clump stars of the same analyzed tiles were selected, and cuts in the color-magnitude diagram were applied and the maximum distance restricted to ~20 kpc in order to construct a similar catalog in terms of distances and covered area compared to the RR Lyrae stars. Results: We report the detection of more than 1000 RR Lyrae ab-type stars in the VVV Survey located in the outskirts of the Galactic bulge

  20. Exploring the Chemical Composition and Double Horizontal Branch of the Bulge Globular Cluster NGC 6569

    Science.gov (United States)

    Johnson, Christian I.; Rich, R. Michael; Caldwell, Nelson; Mateo, Mario; Bailey, John I., III; Olszewski, Edward W.; Walker, Matthew G.

    2018-02-01

    Photometric and spectroscopic analyses have shown that the Galactic bulge cluster Terzan 5 hosts several populations with different metallicities and ages that manifest as a double red horizontal branch (HB). A recent investigation of the massive bulge cluster NGC 6569 revealed a similar, though less extended, HB luminosity split, but little is known about the cluster’s detailed chemical composition. Therefore, we have used high-resolution spectra from the Magellan–M2FS and VLT–FLAMES spectrographs to investigate the chemical compositions and radial velocity distributions of red giant branch and HB stars in NGC 6569. We found the cluster to have a mean heliocentric radial velocity of ‑48.8 km s‑1 (σ = 5.3 km s‑1 148 stars) and =-0.87 dex (19 stars), but the cluster’s 0.05 dex [Fe/H] dispersion precludes a significant metallicity spread. NGC 6569 exhibits light- and heavy-element distributions that are common among old bulge/inner Galaxy globular clusters, including clear (anti)correlations between [O/Fe], [Na/Fe], and [Al/Fe]. The light-element data suggest that NGC 6569 may be composed of at least two distinct populations, and the cluster’s low =-0.11 dex indicates significant pollution with r-process material. We confirm that both HBs contain cluster members, but metallicity and light-element variations are largely ruled out as sources for the luminosity difference. However, He mass fraction differences as small as ΔY ∼ 0.02 cannot be ruled out and may be sufficient to reproduce the double HB.

  1. Chemical Abundances and Ages of the Bulge Stars in APOGEE High-velocity Peaks

    Science.gov (United States)

    Zhou, Yingying; Shen, Juntai; Liu, Chao; Li, Zhao-Yu; Mao, Shude; Kunder, Andrea; Rich, R. Michael; Zasowski, G.; Fernandez-Trincado, J. G.; Majewski, Steven R.; Lin, Chien-Cheng; Geisler, Doug; Tang, Baitian; Villanova, S.; Roman-Lopes, A.; Schultheis, M.; Nidever, David L.; Meza, Andrés; Pan, Kaike; Bizyaev, D. V.

    2017-09-01

    A cold, high-velocity (HV, ˜200 km s-1) peak was first reported in several Galactic bulge fields based on the Apache Point Observatory Galaxy Evolution Experiment (APOGEE) commissioning observations. Both the existence and the nature of the HV peak are still under debate. Here we revisit this feature with the latest APOGEE DR13 data. We find that most of the low-latitude bulge fields display a skewed Gaussian distribution with an HV shoulder. However, only 3 out of 53 fields show distinct HV peaks around 200 km s-1. The velocity distribution can be well described by Gauss-Hermite polynomials, except for the three fields showing clear HV peaks. We find that the correlation between the skewness parameter (h 3) and the mean velocity (\\bar{v}), instead of a distinctive HV peak, is a strong indicator of the bar. It was recently suggested that the HV peak is composed of preferentially young stars. We choose three fields showing clear HV peaks to test this hypothesis using the metallicity, [α/M], and [C/N] as age proxies. We find that both young and old stars show HV features. The similarity between the chemical abundances of stars in the HV peaks and the main component indicates that they are not systematically different in terms of chemical abundance or age. In contrast, there are clear differences in chemical space between stars in the Sagittarius dwarf and the bulge stars. The strong HV peaks off-plane are still to be explained properly and could be different in nature.

  2. On the orbits that generate the X-shape in the Milky Way bulge

    Science.gov (United States)

    Abbott, Caleb G.; Valluri, Monica; Shen, Juntai; Debattista, Victor P.

    2017-09-01

    The Milky Way (MW) bulge shows a boxy/peanut or X-shaped bulge (hereafter BP/X) when viewed in infrared or microwave bands. We examine orbits in an N-body model of a barred disc galaxy that is scaled to match the kinematics of the MW bulge. We generate maps of projected stellar surface density, unsharp masked images, 3D excess-mass distributions (showing mass outside ellipsoids), line-of-sight number count distributions, and 2D line-of-sight kinematics for the simulation as well as co-added orbit families, in order to identify the orbits primarily responsible for the BP/X shape. We estimate that between 19 and 23 per cent of the mass of the bar in this model is associated with the BP/X shape and that the majority of bar orbits contribute to this shape that is clearly seen in projected surface density maps and 3D excess mass for non-resonant box orbits, 'banana' orbits, 'fish/pretzel' orbits and 'brezel' orbits. Although only the latter two families (comprising 7.5 per cent of the total mass) show a distinct X-shape in unsharp masked images, we find that nearly all bar orbit families contribute some mass to the 3D BP/X-shape. All co-added orbit families show a bifurcation in stellar number count distribution with distance that resembles the bifurcation observed in red clump stars in the MW. However, only the box orbit family shows an increasing separation of peaks with increasing galactic latitude |b|, similar to that observed. Our analysis suggests that no single orbit family fully explains all the observed features associated with the MW's BP/X-shaped bulge, but collectively the non-resonant boxes and various resonant boxlet orbits contribute at different distances from the centre to produce this feature. We propose that since box orbits (which are the dominant population in bars) have three incommensurable orbital fundamental frequencies, their 3D shapes are highly flexible and, like Lissajous figures, this family of orbits is most easily able to adapt to

  3. Population synthesis of ultracompact X-ray binaries in the Galactic bulge

    Science.gov (United States)

    van Haaften, L. M.; Nelemans, G.; Voss, R.; Toonen, S.; Portegies Zwart, S. F.; Yungelson, L. R.; van der Sluys, M. V.

    2013-04-01

    Aims: We model the present-day number and properties of ultracompact X-ray binaries (UCXBs) in the Galactic bulge. The main objective is to compare the results to the known UCXB population as well as to data from the Galactic Bulge Survey, in order to learn about the formation of UCXBs and their evolution, such as the onset of mass transfer and late-time behavior. Methods: The binary population synthesis code SeBa and detailed stellar evolutionary tracks have been used to model the UCXB population in the Bulge. The luminosity behavior of UCXBs has been predicted using long-term X-ray observations of the known UCXBs as well as the thermal-viscous disk instability model. Results: In our model, the majority of UCXBs initially have a helium burning star donor. Of the white dwarf donors, most have helium composition. In the absence of a mechanism that destroys old UCXBs, we predict (0.2-1.9) × 105 UCXBs in the Galactic bulge, depending on assumptions, mostly at orbital periods longer than 60 min (a large number of long-period systems also follows from the observed short-period UCXB population). About 5-50 UCXBs should be brighter than 1035 ergs-1, mostly persistent sources with orbital periods shorter than about 30 min and with degenerate helium and carbon-oxygen donors. This is about one order of magnitude more than the observed number of (probably) three. Conclusions: This overprediction of short-period UCXBs by roughly one order of magnitude implies that fewer systems are formed, or that a super-Eddington mass transfer rate is more difficult to survive than we assumed. The very small number of observed long-period UCXBs with respect to short-period UCXBs, the surprisingly high luminosity of the observed UCXBs with orbital periods around 50 min, and the properties of the PSR J1719-1438 system all point to much faster UCXB evolution than expected from angular momentum loss via gravitational wave radiation alone. Old UCXBs, if they still exist, probably have orbital

  4. Towards understanding the dynamics of the bar/bulge region in our Galaxy

    OpenAIRE

    Athanassoula E.

    2012-01-01

    I review some of the work on bars which is closely linked to the bar/bulge system in our Galaxy. Several independent studies, using totally independent methods, come to the same results about the 3D structure of a bar, i.e., that a bar is composed of a vertically thick inner part and a vertically thin outer part. I give examples of this from simulations and substantiate the discussion with input from orbital structure analysis and from observations. The thick part has a considerably shorter r...

  5. Quantum Rényi relative entropies affirm universality of thermodynamics

    Science.gov (United States)

    Misra, Avijit; Singh, Uttam; Bera, Manabendra Nath; Rajagopal, A. K.

    2015-10-01

    We formulate a complete theory of quantum thermodynamics in the Rényi entropic formalism exploiting the Rényi relative entropies, starting from the maximum entropy principle. In establishing the first and second laws of quantum thermodynamics, we have correctly identified accessible work and heat exchange in both equilibrium and nonequilibrium cases. The free energy (internal energy minus temperature times entropy) remains unaltered, when all the entities entering this relation are suitably defined. Exploiting Rényi relative entropies we have shown that this "form invariance" holds even beyond equilibrium and has profound operational significance in isothermal process. These results reduce to the Gibbs-von Neumann results when the Rényi entropic parameter α approaches 1. Moreover, it is shown that the universality of the Carnot statement of the second law is the consequence of the form invariance of the free energy, which is in turn the consequence of maximum entropy principle. Further, the Clausius inequality, which is the precursor to the Carnot statement, is also shown to hold based on the data processing inequalities for the traditional and sandwiched Rényi relative entropies. Thus, we find that the thermodynamics of nonequilibrium state and its deviation from equilibrium together determine the thermodynamic laws. This is another important manifestation of the concepts of information theory in thermodynamics when they are extended to the quantum realm. Our work is a substantial step towards formulating a complete theory of quantum thermodynamics and corresponding resource theory.

  6. Quantum Rényi relative entropies affirm universality of thermodynamics.

    Science.gov (United States)

    Misra, Avijit; Singh, Uttam; Bera, Manabendra Nath; Rajagopal, A K

    2015-10-01

    We formulate a complete theory of quantum thermodynamics in the Rényi entropic formalism exploiting the Rényi relative entropies, starting from the maximum entropy principle. In establishing the first and second laws of quantum thermodynamics, we have correctly identified accessible work and heat exchange in both equilibrium and nonequilibrium cases. The free energy (internal energy minus temperature times entropy) remains unaltered, when all the entities entering this relation are suitably defined. Exploiting Rényi relative entropies we have shown that this "form invariance" holds even beyond equilibrium and has profound operational significance in isothermal process. These results reduce to the Gibbs-von Neumann results when the Rényi entropic parameter α approaches 1. Moreover, it is shown that the universality of the Carnot statement of the second law is the consequence of the form invariance of the free energy, which is in turn the consequence of maximum entropy principle. Further, the Clausius inequality, which is the precursor to the Carnot statement, is also shown to hold based on the data processing inequalities for the traditional and sandwiched Rényi relative entropies. Thus, we find that the thermodynamics of nonequilibrium state and its deviation from equilibrium together determine the thermodynamic laws. This is another important manifestation of the concepts of information theory in thermodynamics when they are extended to the quantum realm. Our work is a substantial step towards formulating a complete theory of quantum thermodynamics and corresponding resource theory.

  7. Thermodynamics in the Viscous Early Universe

    CERN Document Server

    Tawfik, A

    2010-01-01

    Assuming that the matter filling the background geometry in the Early Universe was a free gas and no phase transitions took place, we discuss the thermodynamics of this closed system using classical approaches. We found that essential cosmological quantities, such as the Hubble parameter $H$, the scaling factor $a$ and the curvature parameter $k$, can be derived from this simple model. The results are compatible with the Friedmann-Robertson-Walker model and Einstein field equations. Including finite bulk viscosity coefficient leads to important changes in the cosmological quantities. Accordingly, our picture about evolution of the Universe and its astrophysical consequences seems to be a subject of radical revision. We found that $k$ strongly depends on thermodynamics of the cosmic background matter. The time scale, at which negative curvature might take place, depends on the relation between the matter content and the total energy. Using quantum and statistical approaches, we introduced expressions for $H$ a...

  8. and consequences

    Directory of Open Access Journals (Sweden)

    P. Athanasopoulou

    2011-01-01

    Full Text Available (a Purpose: The purpose of this research is to identify the types of CSR initiatives employed by sports organisations; their antecedents, and their consequences for the company and society. (b Design/methodology/approach: This study is exploratory in nature. Two detailed case studies were conducted involving the football team and the basketball team of one professional, premier league club in Greece and their CSR initiatives. Both teams have the same name, they belong to one of the most popular teams in Greece with a large fan population; have both competed in International Competitions (UEFA’s Champion League; Final Four of the European Tournament and have realised many CSR initiatives in the past. The case studies involved in depth, personal interviews of managers responsible for CSR in each team. Case study data was triangulated with documentation and search of published material concerning CSR actions. Data was analysed with content analysis. (c Findings: Both teams investigated have undertaken various CSR activities the last 5 years, the football team significantly more than the basketball team. Major factors that affect CSR activity include pressure from leagues; sponsors; local community, and global organisations; orientation towards fulfilling their duty to society, and team CSR strategy. Major benefits from CSR include relief of vulnerable groups and philanthropy as well as a better reputation for the firm; increase in fan base; and finding sponsors more easily due to the social profile of the team. However, those benefits are not measured in any way although both teams observe increase in tickets sold; web site traffic and TV viewing statistics after CSR activities. Finally, promotion of CSR is mainly done through web sites; press releases; newspapers, and word-of-mouth communications. (d Research limitations/implications: This study involves only two case studies and has limited generalisability. Future research can extend the

  9. Incidence and Risk Factors for Parastomal Bulging in Patients with Ileostomy or Colostomy: a Register-based Study using data from the Danish Stoma Database Capital Region.

    Science.gov (United States)

    Andersen, Rune M; Klausen, Tobias W; Danielsen, Anne K; Vinther, Anders; Gögenur, Ismail; Thomsen, Thordis

    2017-10-04

    To investigate incidence and risk factors for parastomal bulging, a clinically important complication, in patients with an ileostomy or colostomy. The Danish Stoma Database Capital Region prospectively collects data on patients with a stoma up to a year after surgery. Stoma care nurses clinically assessed the main outcome, parastomal bulging. We linked data from the Stoma Database to data from the Danish Anaesthesia Database. Cumulative incidence of parastomal bulging over the first year was calculated with death and stoma reversal as competing risks. Risk factors were investigated using an exploratory approach. In a study population of 5019, the cumulative incidence (with competing risks) of parastomal bulging was 36.2% at 400 days after surgery. Age, colostomy, male gender, alcohol consumption, and laparoscopy were associated with an increased risk of parastomal bulging. Compared with cancer, inflammatory bowel disease was associated with a lower risk of parastomal bulging, and diverticulitis was associated with a higher risk. Peristomal mesh and stomas placed through a separate incision were associated with a reduction in risk. There was neither increased nor decreased risk of parastomal bulging for body mass index, ASA score, smoking status, emergency surgery, and preoperative stoma site marking. Parastomal bulging was a common complication affecting one in three patients within one year of surgery. Along with previous findings, there is now considerable evidence for age and colostomy as being risk factors for parastomal bulging. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. Thermodynamics of Crystalline States

    CERN Document Server

    Fujimoto, Minoru

    2013-01-01

    Thermodynamics is a well-established discipline of physics for properties of matter in thermal equilibrium with the surroundings. Applying to crystals, however, the laws encounter undefined properties of crystal lattice, which therefore need to be determined for a clear and well-defined description of crystalline states. Thermodynamics of Crystalline States explores the roles played by order variables and dynamic lattices in crystals in a wholly new way. The book begins by clarifying basic concepts for stable crystals. Next, binary phase transitions are discussed to study collective motion of order variables, as described mostly as classical phenomena. New to this edition is the examination of magnetic crystals, where magnetic symmetry is essential for magnetic phase transitions. The multi-electron system is also discussed  theoretically, as a quantum-mechanical example, for superconductivity in metallic crystals. Throughout the book, the role played by the lattice is emphasized and studied in-depth. Thermod...

  11. Mechanics and thermodynamics

    CERN Document Server

    Demtröder, Wolfgang

    2017-01-01

    This introduction to classical mechanics and thermodynamics provides an accessible and clear treatment of the fundamentals. Starting with particle mechanics and an early introduction to special relativity this textbooks enables the reader to understand the basics in mechanics. The text is written from the experimental physics point of view, giving numerous real life examples and applications of classical mechanics in technology. This highly motivating presentation deepens the knowledge in a very accessible way. The second part of the text gives a concise introduction to rotational motion, an expansion to rigid bodies, fluids and gases. Finally, an extensive chapter on thermodynamics and a short introduction to nonlinear dynamics with some instructive examples intensify the knowledge of more advanced topics. Numerous problems with detailed solutions are perfect for self study.

  12. Statistical physics and thermodynamics an introduction to key concepts

    CERN Document Server

    Rau, Jochen

    2017-01-01

    Statistical physics and thermodynamics describe the behaviour of systems on the macroscopic scale. Their methods are applicable to a wide range of phenomena: from refrigerators to the interior of stars, from chemical reactions to magnetism. Indeed, of all physical laws, the laws of thermodynamics are perhaps the most universal. This text provides a concise yet thorough introduction to the key concepts which underlie statistical physics and thermodynamics. It begins with a review of classical probability theory and quantum theory, as well as a careful discussion of the notions of information and entropy, prior to embarking on the development of statistical physics proper. The crucial steps leading from the microscopic to the macroscopic domain are rendered transparent. In particular, the laws of thermodynamics are shown to emerge as natural consequences of the statistical framework. While the emphasis is on clarifying the basic concepts, the text also contains many applications and classroom-tested exercises,...

  13. Thermodynamics and emergent universe

    OpenAIRE

    Ghosh, Saumya; Gangopadhyay, Sunandan

    2016-01-01

    We show that in the isentropic scenario the first order thermodynamical particle creation model gives an emergent universe solution even when the chemical potential is non-zero. However there exists no emergent universe scenario in the second order non-equilibrium theory for the particle creation model. We then point out a correspondence between the particle creation model with barotropic equation of state and the equation of state giving rise to an emergent universe without particle creation...

  14. The discovery of thermodynamics

    Science.gov (United States)

    Weinberger, Peter

    2013-07-01

    Based on the idea that a scientific journal is also an "agora" (Greek: market place) for the exchange of ideas and scientific concepts, the history of thermodynamics between 1800 and 1910 as documented in the Philosophical Magazine Archives is uncovered. Famous scientists such as Joule, Thomson (Lord Kelvin), Clausius, Maxwell or Boltzmann shared this forum. Not always in the most friendly manner. It is interesting to find out, how difficult it was to describe in a scientific (mathematical) language a phenomenon like "heat", to see, how long it took to arrive at one of the fundamental principles in physics: entropy. Scientific progress started from the simple rule of Boyle and Mariotte dating from the late eighteenth century and arrived in the twentieth century with the concept of probabilities. Thermodynamics was the driving intellectual force behind the industrial revolution, behind the enormous social changes caused by this revolution. The history of thermodynamics is a fascinating story, which also gives insights into the mechanism that seem to govern science.

  15. New Insight on the Origin of the Double Red Clump in the Milky Way Bulge

    Science.gov (United States)

    Joo, Seok-Joo; Lee, Young-Wook; Chung, Chul

    2017-05-01

    The double red clump (RC) observed in the Milky Way bulge is widely interpreted as evidence for an X-shaped structure. We have recently suggested, however, an alternative interpretation based on the multiple population phenomenon, where the bright RC is from helium-enhanced second-generation stars (G2), while the faint RC is representing first-generation stars (G1) with normal helium abundance. Here, our RC models are constructed in a large parameter space to see the effects of metallicity, age, and helium abundance on the double RC feature. Our models show that the luminosity of RC stars is mainly affected by helium abundance, while the RC color is primarily affected by metallicity. The effect of age is relatively small, unless it is older than 12 Gyr or much younger than 6 Gyr. The observed double RC feature can therefore be reproduced in a relatively large parameter space, once ΔY between G2 and G1 is assumed to be greater than ˜0.10. We further show that the longitude dependence of the double RC feature at b≈ -8^\\circ , which was pointed out by Gonzalez et al. as a potential problem of our model, is well explained in our scenario by a classical bulge embedded in a tilted bar.

  16. On the kinematic separation of field and cluster stars across the bulge globular NGC 6528

    Energy Technology Data Exchange (ETDEWEB)

    Lagioia, E. P.; Bono, G.; Buonanno, R. [Dipartimento di Fisica, Università degli Studi di Roma-Tor Vergata, via della Ricerca Scientifica 1, I-00133 Roma (Italy); Milone, A. P. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston, ACT 2611 (Australia); Stetson, P. B. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Prada Moroni, P. G. [Dipartimento di Fisica, Università di Pisa, I-56127 Pisa (Italy); Dall' Ora, M. [INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); Aparicio, A.; Monelli, M. [Instituto de Astrofìsica de Canarias, E-38200 La Laguna, Tenerife, Canary Islands (Spain); Calamida, A.; Ferraro, I.; Iannicola, G. [INAF-Osservatorio Astronomico di Roma, Via Frascati 33, I-00044 Monte Porzio Catone (Italy); Gilmozzi, R. [European Southern Observatory, Karl-Schwarzschild-Straße 2, D-85748 Garching (Germany); Matsunaga, N. [Kiso Observatory, Institute of Astronomy, School of Science, The University of Tokyo, 10762-30, Mitake, Kiso-machi, Kiso-gun, 3 Nagano 97-0101 (Japan); Walker, A., E-mail: eplagioia@roma2.infn.it [Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile)

    2014-02-10

    We present deep and precise multi-band photometry of the Galactic bulge globular cluster NGC 6528. The current data set includes optical and near-infrared images collected with ACS/WFC, WFC3/UVIS, and WFC3/IR on board the Hubble Space Telescope. The images cover a time interval of almost 10 yr, and we have been able to carry out a proper-motion separation between cluster and field stars. We performed a detailed comparison in the m {sub F814W}, m {sub F606W} – m {sub F814W} color-magnitude diagram with two empirical calibrators observed in the same bands. We found that NGC 6528 is coeval with and more metal-rich than 47 Tuc. Moreover, it appears older and more metal-poor than the super-metal-rich open cluster NGC 6791. The current evidence is supported by several diagnostics (red horizontal branch, red giant branch bump, shape of the sub-giant branch, slope of the main sequence) that are minimally affected by uncertainties in reddening and distance. We fit the optical observations with theoretical isochrones based on a scaled-solar chemical mixture and found an age of 11 ± 1 Gyr and an iron abundance slightly above solar ([Fe/H] = +0.20). The iron abundance and the old cluster age further support the recent spectroscopic findings suggesting a rapid chemical enrichment of the Galactic bulge.

  17. The Illustris simulation: supermassive black hole-galaxy connection beyond the bulge

    Science.gov (United States)

    Mutlu-Pakdil, Burçin; Seigar, Marc S.; Hewitt, Ian B.; Treuthardt, Patrick; Berrier, Joel C.; Koval, Lauren E.

    2018-02-01

    We study the spiral arm morphology of a sample of the local spiral galaxies in the Illustris simulation and explore the supermassive black hole-galaxy connection beyond the bulge (e.g. spiral arm pitch angle, total stellar mass, dark matter mass, and total halo mass), finding good agreement with other theoretical studies and observational constraints. It is important to study the properties of supermassive black holes and their host galaxies through both observations and simulations and compare their results in order to understand their physics and formative histories. We find that Illustris prediction for supermassive black hole mass relative to pitch angle is in rather good agreement with observations and that barred and non-barred galaxies follow similar scaling relations. Our work shows that Illustris presents very tight correlations between supermassive black hole mass and large-scale properties of the host galaxy, not only for early-type galaxies but also for low-mass, blue and star-forming galaxies. These tight relations beyond the bulge suggest that halo properties determine those of a disc galaxy and its supermassive black hole.

  18. Advancing viral RNA structure prediction: measuring the thermodynamics of pyrimidine-rich internal loops.

    Science.gov (United States)

    Phan, Andy; Mailey, Katherine; Saeki, Jessica; Gu, Xiaobo; Schroeder, Susan J

    2017-05-01

    Accurate thermodynamic parameters improve RNA structure predictions and thus accelerate understanding of RNA function and the identification of RNA drug binding sites. Many viral RNA structures, such as internal ribosome entry sites, have internal loops and bulges that are potential drug target sites. Current models used to predict internal loops are biased toward small, symmetric purine loops, and thus poorly predict asymmetric, pyrimidine-rich loops with >6 nucleotides (nt) that occur frequently in viral RNA. This article presents new thermodynamic data for 40 pyrimidine loops, many of which can form UU or protonated CC base pairs. Uracil and protonated cytosine base pairs stabilize asymmetric internal loops. Accurate prediction rules are presented that account for all thermodynamic measurements of RNA asymmetric internal loops. New loop initiation terms for loops with >6 nt are presented that do not follow previous assumptions that increasing asymmetry destabilizes loops. Since the last 2004 update, 126 new loops with asymmetry or sizes greater than 2 × 2 have been measured. These new measurements significantly deepen and diversify the thermodynamic database for RNA. These results will help better predict internal loops that are larger, pyrimidine-rich, and occur within viral structures such as internal ribosome entry sites. © 2017 Phan et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  19. The Black Hole Mass-Bulge Luminosity Relationship for Active Galactic Nuclei From Reverberation Mapping and Hubble Space Telescope Imaging

    DEFF Research Database (Denmark)

    Bentz, Misty C.; Peterson, Bradley M.; Pogge, Richard W.

    2009-01-01

    We investigate the relationship between black hole mass and bulge luminosity for active galactic nuclei (AGNs) with reverberation-based black hole mass measurements and bulge luminosities from two-dimensional decompositions of Hubble Space Telescope host galaxy images. We find that the slope...... of the relationship for AGNs is 0.76-0.85 with an uncertainty of ~0.1, somewhat shallower than the M BH vprop L 1.0±0.1 relationship that has been fit to nearby quiescent galaxies with dynamical black hole mass measurements. This difference is somewhat perplexing, as the AGN black hole masses include an overall...

  20. Thermodynamics: The Unique Universal Science

    Directory of Open Access Journals (Sweden)

    Wassim M. Haddad

    2017-11-01

    Full Text Available Thermodynamics is a physical branch of science that governs the thermal behavior of dynamical systems from those as simple as refrigerators to those as complex as our expanding universe. The laws of thermodynamics involving conservation of energy and nonconservation of entropy are, without a doubt, two of the most useful and general laws in all sciences. The first law of thermodynamics, according to which energy cannot be created or destroyed, merely transformed from one form to another, and the second law of thermodynamics, according to which the usable energy in an adiabatically isolated dynamical system is always diminishing in spite of the fact that energy is conserved, have had an impact far beyond science and engineering. In this paper, we trace the history of thermodynamics from its classical to its postmodern forms, and present a tutorial and didactic exposition of thermodynamics as it pertains to some of the deepest secrets of the universe.

  1. Thermodynamics of adaptive molecular resolution.

    Science.gov (United States)

    Delgado-Buscalioni, R

    2016-11-13

    A relatively general thermodynamic formalism for adaptive molecular resolution (AMR) is presented. The description is based on the approximation of local thermodynamic equilibrium and considers the alchemic parameter λ as the conjugate variable of the potential energy difference between the atomistic and coarse-grained model Φ=U(1)-U(0) The thermodynamic formalism recovers the relations obtained from statistical mechanics of H-AdResS (Español et al, J. Chem. Phys. 142, 064115, 2015 (doi:10.1063/1.4907006)) and provides relations between the free energy compensation and thermodynamic potentials. Inspired by this thermodynamic analogy, several generalizations of AMR are proposed, such as the exploration of new Maxwell relations and how to treat λ and Φ as 'real' thermodynamic variablesThis article is part of the themed issue 'Multiscale modelling at the physics-chemistry-biology interface'. © 2016 The Author(s).

  2. RNA Thermodynamic Structural Entropy.

    Science.gov (United States)

    Garcia-Martin, Juan Antonio; Clote, Peter

    2015-01-01

    Conformational entropy for atomic-level, three dimensional biomolecules is known experimentally to play an important role in protein-ligand discrimination, yet reliable computation of entropy remains a difficult problem. Here we describe the first two accurate and efficient algorithms to compute the conformational entropy for RNA secondary structures, with respect to the Turner energy model, where free energy parameters are determined from UV absorption experiments. An algorithm to compute the derivational entropy for RNA secondary structures had previously been introduced, using stochastic context free grammars (SCFGs). However, the numerical value of derivational entropy depends heavily on the chosen context free grammar and on the training set used to estimate rule probabilities. Using data from the Rfam database, we determine that both of our thermodynamic methods, which agree in numerical value, are substantially faster than the SCFG method. Thermodynamic structural entropy is much smaller than derivational entropy, and the correlation between length-normalized thermodynamic entropy and derivational entropy is moderately weak to poor. In applications, we plot the structural entropy as a function of temperature for known thermoswitches, such as the repression of heat shock gene expression (ROSE) element, we determine that the correlation between hammerhead ribozyme cleavage activity and total free energy is improved by including an additional free energy term arising from conformational entropy, and we plot the structural entropy of windows of the HIV-1 genome. Our software RNAentropy can compute structural entropy for any user-specified temperature, and supports both the Turner'99 and Turner'04 energy parameters. It follows that RNAentropy is state-of-the-art software to compute RNA secondary structure conformational entropy. Source code is available at https://github.com/clotelab/RNAentropy/; a full web server is available at http

  3. RNA Thermodynamic Structural Entropy.

    Directory of Open Access Journals (Sweden)

    Juan Antonio Garcia-Martin

    Full Text Available Conformational entropy for atomic-level, three dimensional biomolecules is known experimentally to play an important role in protein-ligand discrimination, yet reliable computation of entropy remains a difficult problem. Here we describe the first two accurate and efficient algorithms to compute the conformational entropy for RNA secondary structures, with respect to the Turner energy model, where free energy parameters are determined from UV absorption experiments. An algorithm to compute the derivational entropy for RNA secondary structures had previously been introduced, using stochastic context free grammars (SCFGs. However, the numerical value of derivational entropy depends heavily on the chosen context free grammar and on the training set used to estimate rule probabilities. Using data from the Rfam database, we determine that both of our thermodynamic methods, which agree in numerical value, are substantially faster than the SCFG method. Thermodynamic structural entropy is much smaller than derivational entropy, and the correlation between length-normalized thermodynamic entropy and derivational entropy is moderately weak to poor. In applications, we plot the structural entropy as a function of temperature for known thermoswitches, such as the repression of heat shock gene expression (ROSE element, we determine that the correlation between hammerhead ribozyme cleavage activity and total free energy is improved by including an additional free energy term arising from conformational entropy, and we plot the structural entropy of windows of the HIV-1 genome. Our software RNAentropy can compute structural entropy for any user-specified temperature, and supports both the Turner'99 and Turner'04 energy parameters. It follows that RNAentropy is state-of-the-art software to compute RNA secondary structure conformational entropy. Source code is available at https://github.com/clotelab/RNAentropy/; a full web server is available at http

  4. Time and Thermodynamics

    CERN Document Server

    Kirkland, Kyle

    2007-01-01

    Temperature is vital to the health and welfare of all living beings, and Earth's temperature varies considerably from place to place. Early humans could only live in warm areas such as the tropics. Although modern humans have the technology to keep their houses and offices warm even in cold environments, the growth and development of civilization has created unintentional effects. Cities are warmer than their surrounding regions, and on a global scale, Earth is experiencing rising temperatures. Thus, the science of thermodynamics offers an important tool to study these effects. "Time and

  5. THE PANCHROMATIC HUBBLE ANDROMEDA TREASURY. I. BRIGHT UV STARS IN THE BULGE OF M31

    Energy Technology Data Exchange (ETDEWEB)

    Rosenfield, Philip; Johnson, L. Clifton; Dalcanton, Julianne J.; Williams, Benjamin F.; Gilbert, Karoline M. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Girardi, Leo [Osservatorio Astronomico di Padova-INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Bressan, Alessandro [SISSA, Via Bonomea 265, 34136 Trieste (Italy); Lang, Dustin [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Guhathakurta, Puragra; Dorman, Claire E. [UCO/Lick Observatory and Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Howley, Kirsten M. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Lauer, Tod R.; Olsen, Knut A. G. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Bianchi, Luciana [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Caldwell, Nelson [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street Cambridge, MA 02138 (United States); Dolphin, Andrew [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Kalirai, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Larsen, Soren S. [Astronomical Institute, University of Utrecht, Princetonplein 5, 3584 CC Utrecht (Netherlands); Rix, Hans-Walter [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); and others

    2012-08-20

    As part of the Panchromatic Hubble Andromeda Treasury multi-cycle program, we observed a 12' Multiplication-Sign 6.'5 area of the bulge of M31 with the WFC3/UVIS filters F275W and F336W. From these data we have assembled a sample of {approx}4000 UV-bright, old stars, vastly larger than previously available. We use updated Padova stellar evolutionary tracks to classify these hot stars into three classes: Post-AGB stars (P-AGB), Post-Early AGB (PE-AGB) stars, and AGB-manque stars. P-AGB stars are the end result of the asymptotic giant branch (AGB) phase and are expected in a wide range of stellar populations, whereas PE-AGB and AGB-manque (together referred to as the hot post-horizontal branch; HP-HB) stars are the result of insufficient envelope masses to allow a full AGB phase, and are expected to be particularly prominent at high helium or {alpha} abundances when the mass loss on the red giant branch is high. Our data support previous claims that most UV-bright sources in the bulge are likely hot (extreme) horizontal branch (EHB) stars and their progeny. We construct the first radial profiles of these stellar populations and show that they are highly centrally concentrated, even more so than the integrated UV or optical light. However, we find that this UV-bright population does not dominate the total UV luminosity at any radius, as we are detecting only the progeny of the EHB stars that are the likely source of the UV excess. We calculate that only a few percent of main-sequence stars in the central bulge can have gone through the HP-HB phase and that this percentage decreases strongly with distance from the center. We also find that the surface density of hot UV-bright stars has the same radial variation as that of low-mass X-ray binaries. We discuss age, metallicity, and abundance variations as possible explanations for the observed radial variation in the UV-bright population.

  6. Molecular thermodynamics of nonideal fluids

    CERN Document Server

    Lee, Lloyd L

    2013-01-01

    Molecular Thermodynamics of Nonideal Fluids serves as an introductory presentation for engineers to the concepts and principles behind and the advances in molecular thermodynamics of nonideal fluids. The book covers related topics such as the laws of thermodynamics; entropy; its ensembles; the different properties of the ideal gas; and the structure of liquids. Also covered in the book are topics such as integral equation theories; theories for polar fluids; solution thermodynamics; and molecular dynamics. The text is recommended for engineers who would like to be familiarized with the concept

  7. Thermodynamics of Accelerating Black Holes.

    Science.gov (United States)

    Appels, Michael; Gregory, Ruth; Kubizňák, David

    2016-09-23

    We address a long-standing problem of describing the thermodynamics of an accelerating black hole. We derive a standard first law of black hole thermodynamics, with the usual identification of entropy proportional to the area of the event horizon-even though the event horizon contains a conical singularity. This result not only extends the applicability of black hole thermodynamics to realms previously not anticipated, it also opens a possibility for studying novel properties of an important class of exact radiative solutions of Einstein equations describing accelerated objects. We discuss the thermodynamic volume, stability, and phase structure of these black holes.

  8. Thermodynamics of Fluid Polyamorphism

    Science.gov (United States)

    Anisimov, Mikhail A.; Duška, Michal; Caupin, Frédéric; Amrhein, Lauren E.; Rosenbaum, Amanda; Sadus, Richard J.

    2018-01-01

    Fluid polyamorphism is the existence of different condensed amorphous states in a single-component fluid. It is either found or predicted, usually at extreme conditions, for a broad group of very different substances, including helium, carbon, silicon, phosphorous, sulfur, tellurium, cerium, hydrogen, and tin tetraiodide. This phenomenon is also hypothesized for metastable and deeply supercooled water, presumably located a few degrees below the experimental limit of homogeneous ice formation. We present a generic phenomenological approach to describe polyamorphism in a single-component fluid, which is completely independent of the molecular origin of the phenomenon. We show that fluid polyamorphism may occur either in the presence or in the absence of fluid phase separation depending on the symmetry of the order parameter. In the latter case, it is associated with a second-order transition, such as in liquid helium or liquid sulfur. To specify the phenomenology, we consider a fluid with thermodynamic equilibrium between two distinct interconvertible states or molecular structures. A fundamental signature of this concept is the identification of the equilibrium fraction of molecules involved in each of these alternative states. However, the existence of the alternative structures may result in polyamorphic fluid phase separation only if mixing of these structures is not ideal. The two-state thermodynamics unifies all the debated scenarios of fluid polyamorphism in different areas of condensed-matter physics, with or without phase separation, and even goes beyond the phenomenon of polyamorphism by generically describing the anomalous properties of fluids exhibiting interconversion of alternative molecular states.

  9. Thermodynamics of geothermal fluids

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, P.S.Z.

    1981-03-01

    A model to predict the thermodynamic properties of geothermal brines, based on a minimum amount of experimental data on a few key systems, is tested. Volumetric properties of aqueous sodium chloride, taken from the literature, are represented by a parametric equation over the range 0 to 300{sup 0}C and 1 bar to 1 kbar. Density measurements at 20 bar needed to complete the volumetric description also are presented. The pressure dependence of activity and thermal properties, derived from the volumetric equation, can be used to complete an equation of state for sodium chloride solutions. A flow calorimeter, used to obtain heat capacity data at high temperatures and pressures, is described. Heat capacity measurements, from 30 to 200{sup 0}C and 1 bar to 200 bar, are used to derive values for the activity coefficient and other thermodynamic properties of sodium sulfate solutions as a function of temperature. Literature data on the solubility of gypsum in mixed electrolyte solutions have been used to evaluate model parameters for calculating gypsum solubility in seawater and natural brines. Predictions of strontium and barium sulfate solubility in seawater also are given.

  10. Biochemical Thermodynamics under near Physiological Conditions

    Science.gov (United States)

    Mendez, Eduardo

    2008-01-01

    The recommendations for nomenclature and tables in Biochemical Thermodynamics approved by IUBMB and IUPAC in 1994 can be easily introduced after the chemical thermodynamic formalism. Substitution of the usual standard thermodynamic properties by the transformed ones in the thermodynamic equations, and the use of appropriate thermodynamic tables…

  11. Simulation of disc-bulge-halo galaxies using parallel GPU based codes

    Science.gov (United States)

    Veles, O.; Berczik, P.; Just, A.

    2016-02-01

    We compare the performance of the very popular Tree-GPU code BONSAI with the older Particle-(Multi)Mesh code SUPERBOX. Both code we run on a same hardware using the GPU acceleration for the force calculation. SUPERBOX is a particle-mesh code with high resolution sub-grid and a higher order NGP (nearest grid point) force-calculation scheme. In our research, we are aiming to demonstrate that the new parallel version of SUPERBOX is capable to do the high resolution simulations of the interaction of the system of disc-bulge-halo composed galaxy. We describe the improvement of performance and scalability of SUPERBOX particularly for the Kepler cluster (NVIDIA K20 GPU). A comparison was made with the very popular and publicly available Tree-GPU code BONSAI†.

  12. RR Lyrae star distance scale and kinematics from inner bulge to 50 kpc

    Directory of Open Access Journals (Sweden)

    Dambis Andrei

    2017-01-01

    Full Text Available We use the currently most complete sample of ∼ 3500 type ab RR Lyraes in our Galaxy with available radial-velocity and [Fe/H] measurements to perform a statisticalparallax analysis for a subsample of ∼ 600 type ab RR Lyraes located within 5 kpc from the Sun to refine the parameters of optical and WISE W1-band period-metallicityluminosity relations and adjust our preliminary distances. The new zero point implies the rescaled estimates for the solar Galactocentric distance (RG = 7.99 ± 0.37 kpc and the LMC distance modulus (DMLMC = 18.39 ±0.09. We use the kinematic data for the entire sample to explore the dependence of the halo and thick-disk RR Lyrae velocity ellipsoids on Galactocentric distance from the inner bulge out to R ∼ 50 kpc.

  13. Trifunctional fluorescent unnatural nucleoside: Label free detection of T-T/C-C base mismatches, abasic site and bulge DNA.

    Science.gov (United States)

    Bag, Subhendu Sekhar; Pradhan, Manoj Kumar; Talukdar, Sangita

    2017-08-01

    The detection and targeting of both the mismatched and abasic DNA is highly important which would ultimately help in designing new diagnostics and chemotherapeutics. Furthermore, sensing and targeting the bulge sequence with a fluorescent probe would be useful to study the role of bulges in nucleic acid function or could have significant therapeutic potential. Thus, detection of specific bulges by small fluorescent molecules is an attractive research area since the past several years. Many attempts have been made to prepare such compounds. We report herein a label free strategy for the detection of pyrimidine base mismatches (T/T and C/C), sensing of abasic site, and pyrimidine base bulge DNA using an unnatural tetrazolylpyrene nucleoside ( TPy B Do ) as a bare fluorescent probe. The H-bonding/hydrophobic force mediated interactions allow the sensing of all three deformed DNA via an enhancement of fluorescence signal using our simple "Just-Mix and Read" strategy. The binding of the probe to all the three deformed DNA duplexes is accompanied by an increase in the thermal melting stability of the deformed DNAs. That the probe binds efficiently to the minor groove near the deformed site was evident from spectroscopic studies. All the spectral evidences open up a multitude of possibilities for using our probe, tetrazolylpyrene nucleoside, as an efficient fluorescent light-up bio-probe for label free DNA detection. Copyright © 2017. Published by Elsevier B.V.

  14. LONG-TERM EVOLUTION OF DOME-SHAPED MACULA: Increased Macular Bulge is Associated With Extended Macular Atrophy.

    Science.gov (United States)

    Soudier, Guillaume; Gaudric, Alain; Gualino, Vincent; Massin, Pascale; Nardin, Mathieu; Tadayoni, Ramin; Speeg-Schatz, Claude; Gaucher, David

    2016-05-01

    Dome-shaped macula (DSM) may cause impaired vision. This study analyzed the long-term evolution of DSM, most particularly macular changes: serous retinal detachment, retinal pigment epithelium atrophy, and DSM bulge increase. Twenty-nine eyes presenting with DSM were retrospectively studied. Clinical data, color photographs, fluorescein angiographs, and optical coherence tomography examinations were reviewed. Patients were followed up from 6 months to 111 months (mean, 37.89 months). The height of the macular bulge, the size of retinal pigment epithelium macular atrophy, and serous retinal detachment progression were studied. Other macular changes were noted. Mean vision remained stable. Dome-shaped macula height increased significantly from 338.9 μm to 364.3 μm (P = 0.007). Serous retinal detachment was present initially in 15 of 29 eyes; it increased in 4 cases and resolved spontaneously in 7. Macular retinal pigment epithelium atrophy correlated with the bulge height (P = 0.015), and it enlarged during follow-up (1.12 vs. 1.34, P = 0.04). Other macular anomalies were present initially or appeared during follow-up: macular pucker, choroidal neovascularization (CNV), subretinal pigmentary clumps, and flat irregular pigmented epithelium detachment. A few treatments were proven in serous retinal detachment cases but were ineffective in restoring vision. In DSM, vision may be stable for years while macular changes progress: the macular bulge increases as does retinal pigment epithelium atrophy.

  15. Structure Formation inside Triaxial Dark Matter Halos: Galactic Disks, Bulges, and Bars

    Science.gov (United States)

    Heller, Clayton H.; Shlosman, Isaac; Athanassoula, E.

    2007-12-01

    We investigate formation and evolution of galactic disks immersed in assembling live DM halos. Models have been evolved from cosmological initial conditions and represent the collapse of an isolated density perturbation. The baryons include gas participating in star formation (SF) and stars with the energy feedback onto the ISM. We find that (1) the triaxial halo figure tumbling is insignificant and the angular momentum (J) is channeled into the internal circulation, while the baryonic collapse is stopped by the centrifugal barrier; (2) density response of the (disk) baryons is out of phase with DM, thus washing out the inner halo ellipticity; (3) the total J is neatly conserved, even in models accounting for stellar feedback; (4) the specific J for DM is nearly constant, while that for baryons is decreasing; (5) early stage of disk formation resembles the cat's cradle-a small amorphous disk fueled via radial string patterns-followed by growing oval disk whose shape varies with its orientation to the halo major axis; (6) the disk gas layer thins when the SF rate drops below ~5 Msolar yr-1 (7) about half of the baryons remain outside the disk SF region or in the halo as a hot gas; (8) rotation curves appear to be flat and account for the observed disk/halo contributions; (9) a range of bulge-dominated to bulgeless disks was obtained, depending on the stellar feedback parameter, ɛSF: smaller ɛSF leads to a larger and earlier bulge; lower density threshold for SF leads to a smaller, thicker disk; gas gravitational softening mimics a number of intrinsic processes within the ISM; (10) models are characterized by an extensive bar-forming activity; (11) nested bars form in response to the gas inflow along the primary bars, as shown by Heller, Shlosman, and Athanassoula.

  16. Flow, bulge, and jerk; quantifying surface motions with particle image velocimetry at Volcan Santaiguito (Guatemala) (Invited)

    Science.gov (United States)

    Johnson, J. B.; Andrews, B. J.; Lees, J. M.

    2013-12-01

    Santiaguito's active vent, Caliente, is located 2700 m distant and 1200 m below the summit of neighboring Santa Maria, which provides an ideal vantage point to survey motions of the dynamic surface. With high resolution SLR and video cameras, coupled with strong zoom lenses, we are able to survey motions of this surface at time scales of seconds, minutes, hours, and days. Particle image velocimetry (PIV) is used to quantify motions over the 150-200 m diameter vent region plateau. With video cameras we have observed motions at rapid time scales corresponding to the onset of explosive eruptions, which occur every few hours. For these events the ~30,000 m2 block lava surface temporarily uplifts by as much as 1 m during time scales of about a second. This rapid acceleration is thought to be the source of an equivalent downward force that produces a long period seismic signal. At longer time scales, time lapse camera imagery is used to measure bulging and subsidence of the lava surface. Transient uplift of the central part of the vent plateau is as great as 10 m and occurs over time scales of 15 to 30 minutes. Bulge formation is associated with heightened effusion and subsequent subsidence allows us an estimate of the andesitic/dacitic lava's viscosity. At even longer time scales PIV allows us to track flow of the viscous lava flow and compare observations made in subsequent years. Maximum velocities of about 10 m/day were observed in 2007 and 2009, which was far less than the 50 m/day surface movements detected in 2012 when lava flow effusion was greatly increased. These longer time scale vector flow fields provide important constraints on the relative thicknesses of lava flowing on the dome's surface.

  17. Thermodynamics of disordered Heisenberg model

    Science.gov (United States)

    Mulanix, Michael; Khatami, Ehsan

    Using numerical linked-cluster expansions, we study the thermodynamic properties of the disordered Heisenberg model on the square lattice. We implement a new technique for treating continuous disorder within the NLCE and obtain results for the energy, entropy, specific heat, and spin correlations in the thermodynamic limit.

  18. Thermodynamic aspects of energy conservation

    NARCIS (Netherlands)

    Gool, W. van

    1980-01-01

    Thermodynamics deals with processes in a time independent approach. Industrial productions and many other activities are bound to perform a certain production per unit of time. It will be demonstrated that the stationary process model is a useful tool in relating thermodynamic functions to the

  19. Thermodynamics from Car to Kitchen

    Science.gov (United States)

    Auty, Geoff

    2014-01-01

    The historical background to the laws of thermodynamics is explained using examples we can all observe in the world around us, focusing on motorised transport, refrigeration and solar heating. This is not to be considered as an academic article. The purpose is to improve understanding of thermodynamics rather than impart new knowledge, and for…

  20. The Thermodynamics of Black Holes

    Directory of Open Access Journals (Sweden)

    Wald Robert M.

    2001-01-01

    Full Text Available We review the present status of black hole thermodynamics. Our review includes discussion of classical black hole thermodynamics, Hawking radiation from black holes, the generalized second law, and the issue of entropy bounds. A brief survey also is given of approaches to the calculation of black hole entropy. We conclude with a discussion of some unresolved open issues.

  1. Star Formation in the Local Universe from the CALIFA Sample. II. Activation and Quenching Mechanisms in Bulges, Bars, and Disks

    Science.gov (United States)

    Catalán-Torrecilla, C.; Gil de Paz, A.; Castillo-Morales, A.; Méndez-Abreu, J.; Falcón-Barroso, J.; Bekeraite, S.; Costantin, L.; de Lorenzo-Cáceres, A.; Florido, E.; García-Benito, R.; Husemann, B.; Iglesias-Páramo, J.; Kennicutt, R. C.; Mast, D.; Pascual, S.; Ruiz-Lara, T.; Sánchez-Menguiano, L.; Sánchez, S. F.; Walcher, C. J.; Bland-Hawthorn, J.; Duarte Puertas, S.; Marino, R. A.; Masegosa, J.; Sánchez-Blázquez, P.; CALIFA Collaboration

    2017-10-01

    We estimate the current extinction-corrected Hα star formation rate (SFR) of the different morphological components that shape galaxies (bulges, bars, and disks). We use a multicomponent photometric decomposition based on Sloan Digital Sky Survey imaging to Calar Alto Legacy Integral Field Area Integral Field Spectroscopy (IFS) datacubes for a sample of 219 galaxies. This analysis reveals an enhancement of the central SFR and specific SFR (sSFR = SFR/M ⋆) in barred galaxies. Along the main sequence, we find that more massive galaxies in total have undergone efficient suppression (quenching) of their star formation, in agreement with many studies. We discover that more massive disks have had their star formation quenched as well. We evaluate which mechanisms might be responsible for this quenching process. The presence of type 2 AGNs plays a role at damping the sSFR in bulges and less efficiently in disks. Also, the decrease in the sSFR of the disk component becomes more noticeable for stellar masses around {10}10.5 {M}⊙ ; for bulges, it is already present at ˜ {10}9.5 {M}⊙ . The analysis of the line-of-sight stellar velocity dispersions (σ) for the bulge component and of the corresponding Faber-Jackson relation shows that AGNs tend to have slightly higher σ values than star-forming galaxies for the same mass. Finally, the impact of environment is evaluated by means of the projected galaxy density, Σ5. We find that the SFR of both bulges and disks decreases in intermediate- to high-density environments. This work reflects the potential of combining IFS data with 2D multicomponent decompositions to shed light on the processes that regulate the SFR.

  2. Applied thermodynamics: A new frontier for biotechnology

    DEFF Research Database (Denmark)

    Mollerup, Jørgen

    2006-01-01

    The scientific career of one of the most outstanding scientists in molecular thermodynamics, Professor John M. Prausnitz at Berkeley, reflects the change in the agenda of molecular thermodynamics, from hydrocarbon chemistry to biotechnology. To make thermodynamics a frontier for biotechnology...

  3. Thermodynamic properties of cryogenic fluids

    CERN Document Server

    Leachman, Jacob; Lemmon, Eric; Penoncello, Steven

    2017-01-01

    This update to a classic reference text provides practising engineers and scientists with accurate thermophysical property data for cryogenic fluids. The equations for fifteen important cryogenic fluids are presented in a basic format, accompanied by pressure-enthalpy and temperature-entropy charts and tables of thermodynamic properties. It begins with a chapter introducing the thermodynamic relations and functional forms for equations of state, and goes on to describe the requirements for thermodynamic property formulations, needed for the complete definition of the thermodynamic properties of a fluid. The core of the book comprises extensive data tables and charts for the most commonly-encountered cryogenic fluids. This new edition sees significant updates to the data presented for air, argon, carbon monoxide, deuterium, ethane, helium, hydrogen, krypton, nitrogen and xenon. The book supports and complements NIST’s REFPROP - an interactive database and tool for the calculation of thermodynamic propertie...

  4. Thermodynamics and energy conversion

    CERN Document Server

    Struchtrup, Henning

    2014-01-01

    This textbook gives a thorough treatment of engineering thermodynamics with applications to classical and modern energy conversion devices.   Some emphasis lies on the description of irreversible processes, such as friction, heat transfer and mixing, and the evaluation of the related work losses. Better use of resources requires high efficiencies, therefore the reduction of irreversible losses should be seen as one of the main goals of a thermal engineer. This book provides the necessary tools.   Topics include: car and aircraft engines,  including Otto, Diesel and Atkinson cycles, by-pass turbofan engines, ramjet and scramjet;  steam and gas power plants, including advanced regenerative systems, solar tower, and compressed air energy storage; mixing and separation, including reverse osmosis, osmotic powerplants, and carbon sequestration; phase equilibrium and chemical equilibrium, distillation, chemical reactors, combustion processes, and fuel cells; the microscopic definition of entropy.    The book i...

  5. Thermodynamics of anisotropic branes

    Energy Technology Data Exchange (ETDEWEB)

    Ávila, Daniel [Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, A.P. 70-542, México D.F. 04510 (Mexico); Fernández, Daniel [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 München (Germany); Patiño, Leonardo [Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, A.P. 70-542, México D.F. 04510 (Mexico); Trancanelli, Diego [Institute of Physics, University of São Paulo,05314-970 São Paulo (Brazil)

    2016-11-22

    We study the thermodynamics of flavor D7-branes embedded in an anisotropic black brane solution of type IIB supergravity. The flavor branes undergo a phase transition between a ‘Minkowski embedding’, in which they lie outside of the horizon, and a ‘black hole embedding’, in which they fall into the horizon. This transition depends on the black hole temperature, its degree of anisotropy, and the mass of the flavor degrees of freedom. It happens either at a critical temperature or at a critical anisotropy. A general lesson we learn from this analysis is that the anisotropy, in this particular realization, induces similar effects as the temperature. In particular, increasing the anisotropy bends the branes more and more into the horizon. Moreover, we observe that the transition becomes smoother for higher anisotropies.

  6. Thermodynamics of Protein Aggregation

    Science.gov (United States)

    Osborne, Kenneth L.; Barz, Bogdan; Bachmann, Michael; Strodel, Birgit

    Amyloid protein aggregation characterizes many neurodegenerative disorders, including Alzheimer's, Parkinson's, and Creutz- feldt-Jakob disease. Evidence suggests that amyloid aggregates may share similar aggregation pathways, implying simulation of full-length amyloid proteins is not necessary for understanding amyloid formation. In this study we simulate GNNQQNY, the N-terminal prion-determining domain of the yeast protein Sup35 to investigate the thermodynamics of structural transitions during aggregation. We use a coarse-grained model with replica-exchange molecular dynamics to investigate the association of 3-, 6-, and 12-chain GNNQQNY systems and we determine the aggregation pathway by studying aggregation states of GN- NQQNY. We find that the aggregation of the hydrophilic GNNQQNY sequence is mainly driven by H-bond formation, leading to the formation of /3-sheets from the very beginning of the assembly process. Condensation (aggregation) and ordering take place simultaneously, which is underpinned by the occurrence of a single heat capacity peak only.

  7. Thermodynamics of Fluid Polyamorphism

    Directory of Open Access Journals (Sweden)

    Mikhail A. Anisimov

    2018-01-01

    Full Text Available Fluid polyamorphism is the existence of different condensed amorphous states in a single-component fluid. It is either found or predicted, usually at extreme conditions, for a broad group of very different substances, including helium, carbon, silicon, phosphorous, sulfur, tellurium, cerium, hydrogen, and tin tetraiodide. This phenomenon is also hypothesized for metastable and deeply supercooled water, presumably located a few degrees below the experimental limit of homogeneous ice formation. We present a generic phenomenological approach to describe polyamorphism in a single-component fluid, which is completely independent of the molecular origin of the phenomenon. We show that fluid polyamorphism may occur either in the presence or in the absence of fluid phase separation depending on the symmetry of the order parameter. In the latter case, it is associated with a second-order transition, such as in liquid helium or liquid sulfur. To specify the phenomenology, we consider a fluid with thermodynamic equilibrium between two distinct interconvertible states or molecular structures. A fundamental signature of this concept is the identification of the equilibrium fraction of molecules involved in each of these alternative states. However, the existence of the alternative structures may result in polyamorphic fluid phase separation only if mixing of these structures is not ideal. The two-state thermodynamics unifies all the debated scenarios of fluid polyamorphism in different areas of condensed-matter physics, with or without phase separation, and even goes beyond the phenomenon of polyamorphism by generically describing the anomalous properties of fluids exhibiting interconversion of alternative molecular states.

  8. Thermodynamic Constraints Improve Metabolic Networks.

    Science.gov (United States)

    Krumholz, Elias W; Libourel, Igor G L

    2017-08-08

    In pursuit of establishing a realistic metabolic phenotypic space, the reversibility of reactions is thermodynamically constrained in modern metabolic networks. The reversibility constraints follow from heuristic thermodynamic poise approximations that take anticipated cellular metabolite concentration ranges into account. Because constraints reduce the feasible space, draft metabolic network reconstructions may need more extensive reconciliation, and a larger number of genes may become essential. Notwithstanding ubiquitous application, the effect of reversibility constraints on the predictive capabilities of metabolic networks has not been investigated in detail. Instead, work has focused on the implementation and validation of the thermodynamic poise calculation itself. With the advance of fast linear programming-based network reconciliation, the effects of reversibility constraints on network reconciliation and gene essentiality predictions have become feasible and are the subject of this study. Networks with thermodynamically informed reversibility constraints outperformed gene essentiality predictions compared to networks that were constrained with randomly shuffled constraints. Unconstrained networks predicted gene essentiality as accurately as thermodynamically constrained networks, but predicted substantially fewer essential genes. Networks that were reconciled with sequence similarity data and strongly enforced reversibility constraints outperformed all other networks. We conclude that metabolic network analysis confirmed the validity of the thermodynamic constraints, and that thermodynamic poise information is actionable during network reconciliation. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  9. Thermodynamic Metrics and Optimal Paths

    Energy Technology Data Exchange (ETDEWEB)

    Sivak, David; Crooks, Gavin

    2012-05-08

    A fundamental problem in modern thermodynamics is how a molecular-scale machine performs useful work, while operating away from thermal equilibrium without excessive dissipation. To this end, we derive a friction tensor that induces a Riemannian manifold on the space of thermodynamic states. Within the linear-response regime, this metric structure controls the dissipation of finite-time transformations, and bestows optimal protocols with many useful properties. We discuss the connection to the existing thermodynamic length formalism, and demonstrate the utility of this metric by solving for optimal control parameter protocols in a simple nonequilibrium model.

  10. Statistical Thermodynamics of Disperse Systems

    DEFF Research Database (Denmark)

    Shapiro, Alexander

    1996-01-01

    Principles of statistical physics are applied for the description of thermodynamic equilibrium in disperse systems. The cells of disperse systems are shown to possess a number of non-standard thermodynamic parameters. A random distribution of these parameters in the system is determined....... On the basis of this distribution, it is established that the disperse system has an additional degree of freedom called the macro-entropy. A large set of bounded ideal disperse systems allows exact evaluation of thermodynamic characteristics. The theory developed is applied to the description of equilibrium...

  11. The Thermodynamic Properties of Cubanite

    Science.gov (United States)

    Berger, E. L.; Lauretta, D. S.; Keller, L. P.

    2012-01-01

    CuFe2S3 exists in two polymorphs, a low-temperature orthorhombic form (cubanite) and a high-temperature cubic form (isocubanite). Cubanite has been identified in the CI-chondrite and Stardust collections. However, the thermodynamic properties of cubanite have neither been measured nor estimated. Our derivation of a thermodynamic model for cubanite allows constraints to be placed on the formation conditions. This data, along with the temperature constraint afforded by the crystal structure, can be used to assess the environments in which cubanite formation is (or is not) thermodynamically favored.

  12. Was the Milky Way Bulge Formed from the Buckling Disk Instability, Hierarchical Collapse, Accretion of Clumps, or All of the Above?

    Science.gov (United States)

    Nataf, David M.

    2017-09-01

    The assembly of the Milky Way bulge is an old topic in astronomy, one now in a period of renewed and rapid development. That is due to tremendous advances in observations of bulge stars, motivating observations of both local and high-redshift galaxies, and increasingly sophisticated simulations. The dominant scenario for bulge formation is that of the Milky Way as a nearly pure disk galaxy, with the inner disk having formed a bar and buckled. This can potentially explain virtually all bulge stars with [Fe/H] ≳ -1.0, which comprise 95% of the stellar population. The evidence is the incredible success in N-body models of this type in making non-trivial, non-generic predictions, such as the rotation curve and velocity dispersion measured from radial velocities, and the spatial morphologies of the peanut/X-shape and the long bar. The classical bulge scenario, whereby the bulge formed from early dissipative collapse and mergers, remains viable for stars with [Fe/H] ≲ -1.0 and potentially a minority of the other stars. A classical bulge is expected from Λ-CDM cosmological simulations, can accentuate the properties of an existing bar in a hybrid system, and is most consistent with the bulge abundance trends such as [Mg/Fe], which are elevated relative to both the thin and thick disks. Finally, the clumpy-galaxy scenario is considered, as it is the correct description of most Milky Way precursors given observations of high-redshift galaxies. Simulations predict that these star-forming clumps will sometimes migrate to the centres of galaxies where they may form a bulge, and galaxies often include a bulge clump as well. They will possibly form a bar with properties consistent with those of the Milky Way, such as the exponential profile and metallicity gradient. Given the relative successes of these scenarios, the Milky Way bulge is plausibly of composite origin, with a classical bulge and/or inner halo numerically dominant for stars with [Fe/H] ≲ -1.0, a buckling

  13. Reducing Postoperative Abdominal Bulge Following Deep Inferior Epigastric Perforator Flap Breast Reconstruction with Onlay Monofilament Poly-4-Hydroxybutyrate Biosynthetic Mesh.

    Science.gov (United States)

    Wormer, Blair A; Clavin, Nicholas W; Lefaivre, Jean-Francois; Korn, Jason M; Teng, Edward; Aukskalnis, Anthony S; Robinson, J Michael

    2017-01-01

    Background The purpose of this study was to evaluate the use of a biosynthetic mesh onlay on reducing postoperative abdominal bulge following deep inferior epigastric perforator (DIEP) flap breast reconstruction. Methods All patients undergoing DIEP reconstructions from January, 2010 to January, 2014 at a tertiary center were reviewed. Patients were divided into two groups for comparison based on whether a biosynthetic mesh onlay (Phasix [monofilament poly-4-hydroxybutyrate], Bard Inc., Warwick, RI) was used for reinforcement of the anterior rectus fascia. Rates of postoperative abdominal bulge were compared between the groups utilizing standard statistical methods. Results During the study period, 319 patients underwent 553 DIEP reconstructions, 160 (50.2%) used mesh and 159 (49.8%) did not (nonmesh). The mean follow-up was 16.4 ± 11.1 months. There was no difference in age (49 ± 9.3 years), current tobacco use, diabetes, or mean body mass index (BMI, 29.4 ± 4.4) between the mesh and nonmesh groups (p > 0.05); however, there was a higher proportion of obese patients (BMI > 30) in the mesh group (45.0 vs. 33.3%; p = 0.03). Abdominal bulge rate following DIEP with mesh was lower than the nonmesh group (0 vs. 5.0%; p = 0.004). In the entire sample, 234 (73.4%) underwent bilateral DIEP and 85 (26.6%) underwent unilateral DIEP. In unilateral DIEP patients, the bulge rate was similar between the mesh and nonmesh groups (0 vs. 4.4%; p > 0.05); however, in bilateral DIEP patients, the bulge rate was lower in the mesh group compared with a nonmesh group (0 vs. 5.5%; p = 0.008). Conclusion Reinforcement of the anterior rectus with an onlay monofilament poly-4-hydroxybutyrate biosynthetic mesh may reduce the risk of postoperative bulge rate in patients undergoing DIEP reconstruction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  14. CHARACTERIZATION OF A SAMPLE OF INTERMEDIATE-TYPE ACTIVE GALACTIC NUCLEI. II. HOST BULGE PROPERTIES AND BLACK HOLE MASS ESTIMATES

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, Erika; Cruz-Gonzalez, Irene; Martinez, Benoni; Jimenez-Bailon, Elena [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Apdo. Postal 70-264, Mexico D.F. 04510 (Mexico); Mendez-Abreu, Jairo; Lopez-Martin, Luis [Instituto de Astrofisica de Canarias, E-38200 La Laguna, Tenerife (Spain); Fuentes-Carrera, Isaura [Escuela Superior de Fisica y Matematicas, Instituto Politecnico Nacional (ESFM-IPN), U.P. Adolfo Lopez Mateos, Mexico D.F. 07730 (Mexico); Chavushyan, Vahram [Instituto Nacional de Astrofisica, Optica y Electronica, Apdo. Postal 51-216, 72000 Puebla (Mexico); Leon-Tavares, Jonathan, E-mail: erika@astro.unam.mx [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, 02540 Kylmaelae (Finland)

    2013-02-15

    We present a study of the host bulge properties and their relations with the black hole mass for a sample of 10 intermediate-type active galactic nuclei (AGNs). Our sample consists mainly of early-type spirals, four of them hosting a bar. For 70{sup +10} {sub -17}% of the galaxies, we have been able to determine the type of the bulge, and find that these objects probably harbor a pseudobulge or a combination of classical bulge/pseudobulge, suggesting that pseudobulges might be frequent in intermediate-type AGNs. In our sample, 50% {+-} 14% of the objects show double-peaked emission lines. Therefore, narrow double-peaked emission lines seem to be frequent in galaxies harboring a pseudobulge or a combination of classical bulge/pseudobulge. Depending on the bulge type, we estimated the black hole mass using the corresponding M {sub BH}-{sigma}* relation and found them within a range of 5.69 {+-} 0.21 < log M {sup {sigma}}*{sub BH} < 8.09 {+-} 0.24. Comparing these M {sup {sigma}}*{sub BH} values with masses derived from the FWHM of H{beta} and the continuum luminosity at 5100 A from their SDSS-DR7 spectra (M {sub BH}), we find that 8 out of 10 (80{sup +7} {sub -17}%) galaxies have black hole masses that are compatible within a factor of 3. This result would support that M {sub BH} and M {sup {sigma}}*{sub BH} are the same for intermediate-type AGNs, as has been found for type 1 AGNs. However, when the type of the bulge is taken into account, only three out of the seven (43{sup +18} {sub -15}%) objects of the sample have their M {sup {sigma}}*{sub BH} and M {sub BH} compatible within 3{sigma} errors. We also find that estimations based on the M {sub BH}-{sigma}* relation for pseudobulges are not compatible in 50% {+-} 20% of the objects.

  15. Magnesium isotopes in giants in the Milky Way inner disk and bulge: First results with 3D stellar atmospheres.

    Science.gov (United States)

    Thygesen, Anders; Sbordone, Luca; Christlieb, Norbert; Asplund, Martin

    2015-01-01

    The Milky Way bulge is one of the most poorly understood components of our galaxy and its formation history is still a matter of debate (early collapse vs. disk instability). All knowledge of its chemical evolution history has been so far derived by measuring elemental abundances: no isotopic mixtures have been measured so far in the Bulge. While quite challenging, isotopic measurements can be accomplished with present instruments in bulge stars for a few elements, Magnesium being one of them.Of the three stable Mg isotopes, the most common one, 24Mg, is mainly produced by α capture in SN II, while the other two, 25Mg and 26Mg, can be produced efficiently in massive AGB stars, through the 22Ne(α, n)25Mg(n, γ)26Mg reactions as well as the Mg-Al chain. Moreover, SN II production of 25Mg and 26Mg increases with increasing progenitor metallicity, so in older stellar populations, where only the signature of metal-poor SNe is to be expected, one should not see a significant 25Mg or 26Mg fraction. However, if larger 25Mg/24Mg and 26Mg/24Mg ratios are observed, relative to what is produced in SNe, this is a clear sign of an AGB contribution. As such, Mg isotopic ratios are a very useful probe of AGB pollution onset and chemical enrichment timescale in a stellar population.Here, we present the first ever measurements of Mg isotopes in 7 red giant stars in the Milky Way bulge and inner disk, including two stars in the bulge globular cluster NGC6522. The isotopic abundances have been derived from high resolution, high signal-to-noise VLT-UVES spectra using both standard 1D atmospheric models as well as state-of-the-art 3D hydrodynamical models and spectrosynthesis. The use of 3D atmospheric models impacts the derived ratios and this work represents the first derivation of Mg isotopes using full 3D spectrosynthesis. These results yield new constraints on the proposed formation scenarios of the Milky Way bulge.

  16. Hawking radiation as tunneling and the unified first law of thermodynamics at the apparent horizon in the FRW universe

    OpenAIRE

    Jiang, Ke-Xia; Ke, San-Min; Peng, Dan-Tao; Feng, Jun

    2008-01-01

    Relations between the tunneling rate and the unified first law of thermodynamics at the apparent horizon of the FRW universe are investigated. The tunneling rate arises as a consequence of the unified first law of thermodynamics in such a dynamical system. The analysis shows obviously how the tunneling is intimately connected with the unified first law of thermodynamics through the principle of conservation of energy.

  17. Structure and thermodynamic insights on acetylaminofluorene-modified deletion DNA duplexes as models for frameshift mutagenesis.

    Science.gov (United States)

    Sandineni, Anusha; Lin, Bin; MacKerell, Alexander D; Cho, Bongsup P

    2013-06-17

    2-Acetylaminofluorene (AAF) is a prototype arylamine carcinogen that forms C8-substituted dG-AAF and dG-AF as the major DNA lesions. The bulky N-acetylated dG-AAF lesion can induce various frameshift mutations depending on the base sequence around the lesion. We hypothesized that the thermodynamic stability of bulged-out slipped mutagenic intermediates (SMIs) is directly related to deletion mutations. The objective of the present study was to probe the structural/conformational basis of various dG-AAF-induced SMIs formed during translesion synthesis. We performed spectroscopic, thermodynamic, and molecular dynamics studies of several AAF-modified 16-mer model DNA duplexes, including fully paired and -1, -2, and -3 deletion duplexes of the 5'-CTCTCGATG[FAAF]CCATCAC-3' sequence and an additional -1 deletion duplex of the 5'-CTCTCGGCG[FAAF]CCATCAC-3' NarI sequence. Modified deletion duplexes existed in a mixture of external B and stacked S conformers, with the population of the S conformer being 'GC'-1 (73%) > 'AT'-1 (72%) > full (60%) > -2 (55%) > -3 (37%). Thermodynamic stability was in the order of -1 deletion > -2 deletion > fully paired > -3 deletion duplexes. These results indicate that the stacked S-type conformer of SMIs is thermodynamically more stable than the conformationally flexible external B conformer. Results from the molecular dynamics simulations indicate that perturbation of base stacking dominates the relative stability along with contributions from bending, duplex dynamics, and solvation effects that are important in specific cases. Taken together, these results support a hypothesis that the conformational and thermodynamic stabilities of the SMIs are critical determinants for the induction of frameshift mutations.

  18. Thermodynamical string fragmentation

    Science.gov (United States)

    Fischer, Nadine; Sjöstrand, Torbjörn

    2017-01-01

    The observation of heavy-ion-like behaviour in pp collisions at the LHC suggests that more physics mechanisms are at play than traditionally assumed. The introduction e.g. of quark-gluon plasma or colour rope formation can describe several of the observations, but as of yet there is no established paradigm. In this article we study a few possible modifications to the Pythia event generator, which describes a wealth of data but fails for a number of recent observations. Firstly, we present a new model for generating the transverse momentum of hadrons during the string fragmentation process, inspired by thermodynamics, where heavier hadrons naturally are suppressed in rate but obtain a higher average transverse momentum. Secondly, close-packing of strings is taken into account by making the temperature or string tension environment-dependent. Thirdly, a simple model for hadron rescattering is added. The effect of these modifications is studied, individually and taken together, and compared with data mainly from the LHC. While some improvements can be noted, it turns out to be nontrivial to obtain effects as big as required, and further work is called for.

  19. Association theories for complex thermodynamics

    DEFF Research Database (Denmark)

    Kontogeorgis, Georgios; Rafiqul Gani

    2013-01-01

    Thermodynamics of complex systems (e.g. with associating molecules, multicomponent mixtures, multiphase equilibria, wide ranges of conditions, estimation of many different properties simultaneously) is a topic of great importance in chemical engineering and for a wide range of industrial...... promising direction for a general and useful for engineering purposes modeling of complex thermodynamics is via the use of association theories e.g. those based on chemical theory (like APACT), or on the lattice theory (like NRHB) or those based on perturbation theory (like SAFT and CPA). The purpose...... applications. While specialized models can handle different cases, even complex ones, with the advent of powerful theories and computers there is the hope that a single or a few models could be suitable for a general modeling of complex thermodynamics. After more than 100 years with active use of thermodynamic...

  20. Experimental approaches to membrane thermodynamics

    DEFF Research Database (Denmark)

    Westh, Peter

    2009-01-01

    Thermodynamics describes a system on the macroscopic scale, yet it is becoming an important tool for the elucidation of many specific molecular aspects of membrane properties. In this note we discuss this application of thermodynamics, and give a number of examples on how thermodynamic measuremen...... have contributed to the understanding of specific membrane phenomena. We mainly focus on non-specific interactions of bilayers and small molecules (water and solutes) in the surrounding solvent, and the changes in membrane properties they bring about. Differences between thermodynamic...... and stoichiometric (structural) definitions of non-specific binding or partitioning are emphasized, and it is concluded that this distinction is important for weak, but not for strong, interactions....

  1. Spectrophotometric Determination and Thermodynamic Parameters ...

    African Journals Online (AJOL)

    Erah

    Spectrophotometric Determination and Thermodynamic. Parameters of Charge Transfer Complexation Between. Stavudine and Chloranilic Acid. Wilfred O Obonga, Edwin O Omeje*, Philip F Uzor and Malachy O Ugwu. Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University ...

  2. Shock Thermodynamic Applied Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Shock Thermodynamic Applied Research Facility (STAR) facility, within Sandia’s Solid Dynamic Physics Department, is one of a few institutions in the world with a...

  3. Thermodynamics from concepts to applications

    CERN Document Server

    Shavit, Arthur

    2008-01-01

    The book presents a logical methodology for solving problems in the context of conservation laws and property tables or equations. The authors elucidate the terms around which thermodynamics has historically developed, such as work, heat, temperature, energy, and entropy. Using a pedagogical approach that builds from basic principles to laws and eventually corollaries of the laws, the text enables students to think in clear and correct thermodynamic terms as well as solve real engineering problems.

  4. Thermodynamics of Asymptotically Conical Geometries.

    Science.gov (United States)

    Cvetič, Mirjam; Gibbons, Gary W; Saleem, Zain H

    2015-06-12

    We study the thermodynamical properties of a class of asymptotically conical geometries known as "subtracted geometries." We derive the mass and angular momentum from the regulated Komar integral and the Hawking-Horowitz prescription and show that they are equivalent. By deriving the asymptotic charges, we show that the Smarr formula and the first law of thermodynamics hold. We also propose an analog of Christodulou-Ruffini inequality. The analysis can be generalized to other asymptotically conical geometries.

  5. THERRP: a thermodynamic properties program

    Energy Technology Data Exchange (ETDEWEB)

    Deeds, R.S.

    1977-05-01

    The computer program THERPP, a program that calculates the thermodynamic properties of light hydrocarbons and mixtures of light hydrocarbons is documented. A specific pressure--temperature or pressure--enthalpy grid is input to obtain properties in the desired region. THERPP is a modification of the program HSGC. Thermodynamic properties are calculated using Starling's modification to the Benedict-Webb-Rubin equation of state.

  6. Thermodynamics of nonsingular bouncing universes

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Pedro C. [Universidade Federal do Rio Grande do Norte, Escola de Ciencias e Tecnologia, Natal, Rio Grande do Norte (Brazil); Pavon, Diego [Universidad Autonoma de Barcelona, Departamento de Fisica, Bellaterra, Barcelona (Spain)

    2016-01-15

    Homogeneous and isotropic, nonsingular, bouncing world models are designed to evade the initial singularity at the beginning of the cosmic expansion. Here, we study the thermodynamics of the subset of these models governed by general relativity. Considering the entropy of matter and radiation and considering the entropy of the apparent horizon to be proportional to its area, we argue that these models do not respect the generalized second law of thermodynamics, also away from the bounce. (orig.)

  7. Generalization of Gibbs Entropy and Thermodynamic Relation

    OpenAIRE

    Park, Jun Chul

    2010-01-01

    In this paper, we extend Gibbs's approach of quasi-equilibrium thermodynamic processes, and calculate the microscopic expression of entropy for general non-equilibrium thermodynamic processes. Also, we analyze the formal structure of thermodynamic relation in non-equilibrium thermodynamic processes.

  8. Bulge Testing and Interface Fracture Characterization of Plasma-Sprayed and HIP Bonded Zr Coatings on U-Mo

    Science.gov (United States)

    Hollis, K.; Liu, C.; Leckie, R.; Lovato, M.

    2015-01-01

    Bulge testing using a pressurized fluid to fracture the interface between bonded material layers along with three-dimensional digital image correlation to measure the sample distortion caused by pressurized fluid was applied to plasma-sprayed coatings. The initiation fracture toughness associated with the bonded materials was measured during the testing. The bulge testing of the uranium-molybdenum alloy plasma sprayed with zirconium and clad in aluminum is presented. The initiation fracture toughness was observed to increase with the increasing cathodic arc-cleaning current and the use of alternating polarity transferred arc current. This dependence was linked to the interface composition of oxide and mixed metal phases along with the interface temperature during spray deposition.

  9. Surface Roughening Behavior of 6063 Aluminum Alloy during Bulging by Spun Tubes

    Directory of Open Access Journals (Sweden)

    Yang Cai

    2017-03-01

    Full Text Available Severe surface roughening during the hydroforming of aluminum alloy parts can produce surface defects that severely restrict their application in the automobile and aerospace industry. To understand the relation between strain, grain size and surface roughness under biaxial stress conditions, hydro-bulging tests of aluminum alloy tubes were carried out, and the tubes with different grain sizes were prepared by a spinning and annealing process. The surface roughness was measured by a laser scanning confocal microscope to evaluate the surface roughening macroscopical behavior, and the corresponding microstructures were observed using electron back-scattered diffraction (EBSD to reveal the roughening microscopic behavior. The results obtained show that the surface roughness increased with both strain and grain size under biaxial stress. No surface defects were observed on the surface when the grain size was less than 105 μm if the strain was less than 18%, or when the grain size was between 130 and 175 μm if the strain was less than 15.88% and 7.15%, respectively. The surface roughening microscopic behavior was identified as an inhomogeneous grain size distribution, which became more pronounced with increasing grain size and resulted in greater local deformation. Concentrated grain orientation also results in severe inhomogeneous deformation during plastics deformation, and serious surface roughening.

  10. Abundances in Galactic bulge planetary nebulae from optical, ultraviolet and infrared observations

    Science.gov (United States)

    Smith, Christina L.; Zijlstra, Albert A.; Gesicki, Krzysztof M.; Dinerstein, Harriet L.

    2017-11-01

    Iron suffers from high levels of depletion in the highly ionized environments of planetary nebulae, making the direct determination of undepleted elemental iron abundances difficult. Zinc, which does not suffer from the same depletion effects as iron, may be used as a surrogate element to measure iron abundances as there is an approximately constant zinc-to-iron ratio across a wide range of metallicities. In this paper, we report zinc abundances of six Galactic bulge planetary nebulae determined from new observations taken with Infrared Spectrometer And Array Camera (ISAAC) on the Very Large Telescope, Chile, prior to the instrument's decommissioning as well as a further three based upon literature observations. Ultraviolet and Visual Echelle Spectrograph (UVES) data of the sample planetary nebulae are presented and have been used to derive abundances, temperatures and densities of a variety of elements and ions. The abundances derived from the UVES data agree well with results from the literature. [Zn/H], determined from the ISAAC observations, is found to be generally subsolar and [O/Zn] is found to be either consistent or enriched with respect to solar.

  11. Black Holes and Galactic Density Cusps III From Black Hole to Bulge

    CERN Document Server

    Henriksen, Richard N; Macmillan, Joseph D

    2011-01-01

    Aims. In this paper we continue our study of density cusps that may contain central black holes. Methods. We recall our attempts to use distribution functions with a memory of self-similar relaxation, but mostly they apply only in restricted regions of the global system. We are forced to consider related distribution functions that are steady but not self-similar. Results. One remarkably simple distribution function that has a filled loss cone describes a bulge that transits from a near black hole domain to an outer 'zero flux' regime where$\\rho\\propto r^{-7/4}$. The transition passes from an initial inverse square profile through a region having a 1/r density profile. The structure is likely to be developed at an early stage in the growth of a galaxy. A central black hole is shown to grow exponentially in this background with an e-folding time of a few million years. Conclusions. We derive our results from first principles, using only the angular momentum integral in spherical symmetry. The initial relaxatio...

  12. Spectroscopic classification of X-ray sources in the Galactic Bulge Survey

    Science.gov (United States)

    Wevers, T.; Torres, M. A. P.; Jonker, P. G.; Nelemans, G.; Heinke, C.; Mata Sánchez, D.; Johnson, C. B.; Gazer, R.; Steeghs, D. T. H.; Maccarone, T. J.; Hynes, R. I.; Casares, J.; Udalski, A.; Wetuski, J.; Britt, C. T.; Kostrzewa-Rutkowska, Z.; Wyrzykowski, Ł.

    2017-10-01

    We present the classification of 26 optical counterparts to X-ray sources discovered in the Galactic Bulge Survey. We use (time-resolved) photometric and spectroscopic observations to classify the X-ray sources based on their multiwavelength properties. We find a variety of source classes, spanning different phases of stellar/binary evolution. We classify CX21 as a quiescent cataclysmic variable (CV) below the period gap, and CX118 as a high accretion rate (nova-like) CV. CXB12 displays excess UV emission, and could contain a compact object with a giant star companion, making it a candidate symbiotic binary or quiescent low-mass X-ray binary (although other scenarios cannot be ruled out). CXB34 is a magnetic CV (polar) that shows photometric evidence for a change in accretion state. The magnetic classification is based on the detection of X-ray pulsations with a period of 81 ± 2 min. CXB42 is identified as a young stellar object, namely a weak-lined T Tauri star exhibiting (to date unexplained) UX Ori-like photometric variability. The optical spectrum of CXB43 contains two (resolved) unidentified double-peaked emission lines. No known scenario, such as an active galactic nucleus or symbiotic binary, can easily explain its characteristics. We additionally classify 20 objects as likely active stars based on optical spectroscopy, their X-ray to optical flux ratios and photometric variability. In four cases we identify the sources as binary stars.

  13. Crack formation on metal foils during high dynamic and quasi-static bulge test

    Science.gov (United States)

    Veenaas, S.; Vollertsen, F.

    2017-09-01

    Resource efficiency combined with high-strength materials is the key to enable intelligent lightweight design. Forming processes, such as high speed forming processes, have a high degree of material utilization compared to other manufacturing processes. In the micro range, processes based on laser induced shockwaves are promising for high speed forming operations. High speed forming offers the possibility to achieve high strain rates and accordingly the forming limit of thin metallic foils can be increased compared to conventional forming operation. However, the effect of the increased forming limit is not completely understood. Therefore, in this work the position of the crack initiation is investigated for quasi-static and dynamic bulge tests. The investigated material is Al99.5 and CU-ETP1 in the thicknesses of 20 μm and 50 μm. It is found, that the crack formation for quasi-static forming is showing a stochastic distribution over the formed area, while the crack initiation for the dynamic forming process is in the centre. This behaviour is explained by an increase in material temperature during the laser shock forming process, which is decreasing the flow stress in the centre of the forming area, thus the crack initiation is located in this area.

  14. Thermodynamics of firms' growth

    Science.gov (United States)

    Zambrano, Eduardo; Hernando, Alberto; Hernando, Ricardo; Plastino, Angelo

    2015-01-01

    The distribution of firms' growth and firms' sizes is a topic under intense scrutiny. In this paper, we show that a thermodynamic model based on the maximum entropy principle, with dynamical prior information, can be constructed that adequately describes the dynamics and distribution of firms' growth. Our theoretical framework is tested against a comprehensive database of Spanish firms, which covers, to a very large extent, Spain's economic activity, with a total of 1 155 142 firms evolving along a full decade. We show that the empirical exponent of Pareto's law, a rule often observed in the rank distribution of large-size firms, is explained by the capacity of economic system for creating/destroying firms, and that can be used to measure the health of a capitalist-based economy. Indeed, our model predicts that when the exponent is larger than 1, creation of firms is favoured; when it is smaller than 1, destruction of firms is favoured instead; and when it equals 1 (matching Zipf's law), the system is in a full macroeconomic equilibrium, entailing ‘free’ creation and/or destruction of firms. For medium and smaller firm sizes, the dynamical regime changes, the whole distribution can no longer be fitted to a single simple analytical form and numerical prediction is required. Our model constitutes the basis for a full predictive framework regarding the economic evolution of an ensemble of firms. Such a structure can be potentially used to develop simulations and test hypothetical scenarios, such as economic crisis or the response to specific policy measures. PMID:26510828

  15. Condensation: Passenger Not Driver in Atmospheric Thermodynamics

    OpenAIRE

    Jack Denur

    2016-01-01

    The second law of thermodynamics states that processes yielding work or at least capable of yielding work are thermodynamically spontaneous, and that those costing work are thermodynamically nonspontaneous. Whether a process yields or costs heat is irrelevant. Condensation of water vapor yields work and hence is thermodynamically spontaneous only in a supersaturated atmosphere; in an unsaturated atmosphere it costs work and hence is thermodynamically nonspontaneous. Far more of Earth’s atmosp...

  16. A thermodynamic theory of microbial growth

    Science.gov (United States)

    Desmond-Le Quéméner, Elie; Bouchez, Théodore

    2014-01-01

    Our ability to model the growth of microbes only relies on empirical laws, fundamentally restricting our understanding and predictive capacity in many environmental systems. In particular, the link between energy balances and growth dynamics is still not understood. Here we demonstrate a microbial growth equation relying on an explicit theoretical ground sustained by Boltzmann statistics, thus establishing a relationship between microbial growth rate and available energy. The validity of our equation was then questioned by analyzing the microbial isotopic fractionation phenomenon, which can be viewed as a kinetic consequence of the differences in energy contents of isotopic isomers used for growth. We illustrate how the associated theoretical predictions are actually consistent with recent experimental evidences. Our work links microbial population dynamics to the thermodynamic driving forces of the ecosystem, which opens the door to many biotechnological and ecological developments. PMID:24522260

  17. Thermodynamics of weight loss diets

    Directory of Open Access Journals (Sweden)

    Fine Eugene J

    2004-12-01

    Full Text Available Abstract Background It is commonly held that "a calorie is a calorie", i.e. that diets of equal caloric content will result in identical weight change independent of macronutrient composition, and appeal is frequently made to the laws of thermodynamics. We have previously shown that thermodynamics does not support such a view and that diets of different macronutrient content may be expected to induce different changes in body mass. Low carbohydrate diets in particular have claimed a "metabolic advantage" meaning more weight loss than in isocaloric diets of higher carbohydrate content. In this review, for pedagogic clarity, we reframe the theoretical discussion to directly link thermodynamic inefficiency to weight change. The problem in outline: Is metabolic advantage theoretically possible? If so, what biochemical mechanisms might plausibly explain it? Finally, what experimental evidence exists to determine whether it does or does not occur? Results Reduced thermodynamic efficiency will result in increased weight loss. The laws of thermodynamics are silent on the existence of variable thermodynamic efficiency in metabolic processes. Therefore such variability is permitted and can be related to differences in weight lost. The existence of variable efficiency and metabolic advantage is therefore an empiric question rather than a theoretical one, confirmed by many experimental isocaloric studies, pending a properly performed meta-analysis. Mechanisms are as yet unknown, but plausible mechanisms at the metabolic level are proposed. Conclusions Variable thermodynamic efficiency due to dietary manipulation is permitted by physical laws, is supported by much experimental data, and may be reasonably explained by plausible mechanisms.

  18. Galactic bulge population II Cepheids in the VVV survey: period-luminosity relations and a distance to the Galactic centre

    Science.gov (United States)

    Bhardwaj, A.; Rejkuba, M.; Minniti, D.; Surot, F.; Valenti, E.; Zoccali, M.; Gonzalez, O. A.; Romaniello, M.; Kanbur, S. M.; Singh, H. P.

    2017-09-01

    Context. Multiple stellar populations of different ages and metallicities reside in the Galactic bulge that trace its structure and provide clues to its formation and evolution. Aims: We present the near-infrared observations of population II Cepheids in the Galactic bulge from VISTA Variables in the Vía Láctea (VVV) survey. The JHKs photometry together with optical data from Optical Gravitational Lensing Experiment (OGLE) survey provide an independent estimate of the distance to the Galactic centre. The old, metal-poor and low-mass population II Cepheids are also investigated as useful tracers for the structure of the Galactic bulge. Methods: We identify 340 population II Cepheids in the VVV survey Galactic bulge catalogue based on their match with the OGLE-III Catalogue. The single-epoch JH and multi-epoch Ks observations complement the accurate periods and optical (VI) mean-magnitudes from OGLE. The sample consisting of BL Herculis and W Virginis subtypes is used to derive period-luminosity relations after correcting mean-magnitudes for the extinction. Our Ks-band period-luminosity relation, Ks = -2.189(0.056) [log (P)-1] + 11.187(0.032), is consistent with published work for BL Herculis and W Virginis variables in the Large Magellanic Cloud. Results: We present a combined OGLE-III and VVV catalogue with periods, classification, mean magnitudes, and extinction for 264 Galactic bulge population II Cepheids that have good-quality Ks-band light curves. The absolute magnitudes for population II Cepheids and RR Lyraes calibrated using Gaia and Hubble Space Telescope parallaxes, together with calibrated magnitudes for Large Magellanic Cloud population II Cepheids, are used to obtain a distance to the Galactic centre, R0 = 8.34 ± 0.03(stat.) ± 0.41(syst.), which changes by with different extinction laws. While noting the limitation of small number statistics, we find that the present sample of population II Cepheids in the Galactic bulge shows a nearly spheroidal

  19. Towards understanding the dynamics of the bar/bulge region in our Galaxy

    Directory of Open Access Journals (Sweden)

    Athanassoula E.

    2012-02-01

    Full Text Available I review some of the work on bars which is closely linked to the bar/bulge system in our Galaxy. Several independent studies, using totally independent methods, come to the same results about the 3D structure of a bar, i.e., that a bar is composed of a vertically thick inner part and a vertically thin outer part. I give examples of this from simulations and substantiate the discussion with input from orbital structure analysis and from observations. The thick part has a considerably shorter radial extent than the thin part. I then see how this applies to our Galaxy, where two bars have been reported, the COBE/DIRBE bar and the Long bar. Comparing their extents and making the reasonable and necessary assumption that our Galaxy has properties similar to those of other galaxies of similar type, leads to the conclusion that these two bars can not form a standard double bar system. I then discuss arguments in favour of the two bars being simply different parts of the same bar, the COBE/DIRBE bar being the thick inner part and the Long bar being the thin outer part of this bar. I also very briefly discuss some related new results. I first consider bar formation and evolution in disc galaxies with a gaseous component – including star formation, feedback and evolution – and a triaxial halo. Then I consider bar formation in a fully cosmological context using hydrodynamical LCDM simulations, where the host galaxies grow, accrete matter and significantly evolve during the formation and evolution of the bar.

  20. Thermodynamics of quantum information scrambling.

    Science.gov (United States)

    Campisi, Michele; Goold, John

    2017-06-01

    Scrambling of quantum information can conveniently be quantified by so-called out-of-time-order correlators (OTOCs), i.e., correlators of the type 〈[W_{τ},V]^{†}[W_{τ},V]〉, whose measurements present a formidable experimental challenge. Here we report on a method for the measurement of OTOCs based on the so-called two-point measurement scheme developed in the field of nonequilibrium quantum thermodynamics. The scheme is of broader applicability than methods employed in current experiments and provides a clear-cut interpretation of quantum information scrambling in terms of nonequilibrium fluctuations of thermodynamic quantities, such as work and heat. Furthermore, we provide a numerical example on a spin chain which highlights the utility of our thermodynamic approach when understanding the differences between integrable and ergodic behaviors. We also discuss how the method can be used to extend the reach of current experiments.

  1. Nanofluidics thermodynamic and transport properties

    CERN Document Server

    Michaelides, Efstathios E (Stathis)

    2014-01-01

    This volume offers a comprehensive examination of the subject of heat and mass transfer with nanofluids as well as a critical review of the past and recent research projects in this area. Emphasis is placed on the fundamentals of the transport processes using particle-fluid suspensions, such as nanofluids. The nanofluid research is examined and presented in a holistic way using a great deal of our experience with the subjects of continuum mechanics, statistical thermodynamics, and non-equilibrium thermodynamics of transport processes. Using a thorough database, the experimental, analytical, and numerical advances of recent research in nanofluids are critically examined and connected to past research with medium and fine particles as well as to functional engineering systems. Promising applications and technological issues of heat/mass transfer system design with nanofluids are also discussed. This book also: Provides a deep scientific analysis of nanofluids using classical thermodynamics and statistical therm...

  2. Thermodynamics a complete undergraduate course

    CERN Document Server

    Steane, Andrew M

    2016-01-01

    This is an undergraduate textbook in thermodynamics—the science of heat, work, temperature, and entropy. The text presents thermodynamics in and of itself, as an elegant and powerful set of ideas and methods. These methods open the way to understanding a very wide range of phenomena in physics, chemistry, engineering, and biology. Starting out from an introduction of concepts at first year undergraduate level, the roles of temperature, internal energy, and entropy are explained via the laws of thermodynamics. The text employs a combination of examples, exercises, and careful discussion, with a view to conveying the feel of the subject as well as avoiding common misunderstandings. The Feynman–Smuluchowski ratchet, Szilard’s engine, and Maxwell’s daemon are used to elucidate entropy and the second law. Free energy and thermodynamic potentials are discussed at length, with applications to solids as well as fluids and flow processes. Thermal radiation is discussed, and the main ideas significant to global...

  3. The Thermodynamic Machinery of Life

    CERN Document Server

    Kurzynski, Michal

    2006-01-01

    Living organisms are open thermodynamic systems whose functional structure has developed and been kinetically frozen during the historical process of biological evolution. A thermodynamics of both nonequilibrium and complex systems is needed for their description. In this book, the foundations of such a thermodynamics are presented. Biological processes at the cellular level are considered as coupled chemical reactions and transport processes across internal and the cytoplasmic membrane. All these processes are catalyzed by specific enzymes hence the kinetics of enzymatic catalysis and its control are described here in detail. The coupling of several processes through a common enzyme is considered in the context of free energy or signal transduction. Special attention is paid to evidence for a rich stochastic internal dynamics of native proteins and its possible role in the control of enzyme activity and in the action of biological molecular machines.

  4. Statistical thermodynamics of clustered populations.

    Science.gov (United States)

    Matsoukas, Themis

    2014-08-01

    We present a thermodynamic theory for a generic population of M individuals distributed into N groups (clusters). We construct the ensemble of all distributions with fixed M and N, introduce a selection functional that embodies the physics that governs the population, and obtain the distribution that emerges in the scaling limit as the most probable among all distributions consistent with the given physics. We develop the thermodynamics of the ensemble and establish a rigorous mapping to regular thermodynamics. We treat the emergence of a so-called giant component as a formal phase transition and show that the criteria for its emergence are entirely analogous to the equilibrium conditions in molecular systems. We demonstrate the theory by an analytic model and confirm the predictions by Monte Carlo simulation.

  5. Specificity of the double-stranded RNA-binding domain from the RNA-activated protein kinase PKR for double-stranded RNA: insights from thermodynamics and small-angle X-ray scattering.

    Science.gov (United States)

    Patel, Sunita; Blose, Joshua M; Sokoloski, Joshua E; Pollack, Lois; Bevilacqua, Philip C

    2012-11-20

    The interferon-inducible, double-stranded (ds) RNA-activated protein kinase (PKR) contains a dsRNA-binding domain (dsRBD) and plays key roles in viral pathogenesis and innate immunity. Activation of PKR is typically mediated by long dsRNA, and regulation of PKR is disfavored by most RNA imperfections, including bulges and internal loops. Herein, we combine isothermal titration calorimetry (ITC), electrophoretic mobility shift assays, and small-angle X-ray scattering (SAXS) to dissect the thermodynamic basis for the specificity of the dsRBD termed "p20" for various RNAs and to detect any RNA conformational changes induced upon protein binding. We monitor binding of p20 to chimeric duplexes containing terminal RNA-DNA hybrid segments and a central dsRNA segment, which was either unbulged ("perfect") or bulged. The ITC data reveal strong binding of p20 to the perfect duplex (K(d) ~ 30 nM) and weaker binding to the bulged duplex (K(d) ~ 2-5 μM). SAXS reconstructions and p(r) distance distribution functions further uncover that p20 induces no significant conformational change in perfect dsRNA but largely straightens bulged dsRNA. Together, these observations support the dsRBD's ability to tightly bind to only A-form RNA and suggest that in a noninfected cell, PKR may be buffered via weak interactions with various bulged and looped RNAs, which it may straighten. This work suggests that PKR-regulating RNAs with complex secondary and tertiary structures likely mimic dsRNA and/or engage portions of PKR outside of the dsRBD.

  6. An introduction to endoreversible thermodynamics

    Directory of Open Access Journals (Sweden)

    Hoffmann, Karl Heinz

    2008-02-01

    Full Text Available Reversible thermodynamic processes are convenient abstractions of real processes, which are always irreversible. Approaching the reversible regime means to become more and more quasistatic, letting behind processes which achieve any kind of finite transformation rate for the quantities studied. On the other hand studying processes with finite transformation rates means to deal with irreversibilities and in many cases these irreversibilities must be included in a realistic description of such processes. Endoreversible thermodynamics is a non-equilibrium approach in this direction by viewing a system as a network of internally reversible (endoreversible subsystems exchanging energy in an irreversible fashion. This material provides an introduction to the subject.

  7. Interfacial thermodynamics of water and six other liquid solvents.

    Science.gov (United States)

    Pascal, Tod A; Goddard, William A

    2014-06-05

    We examine the thermodynamics of the liquid-vapor interface by direct calculation of the surface entropy, enthalpy, and free energy from extensive molecular dynamics simulations using the two-phase thermodynamics (2PT) method. Results for water, acetonitrile, cyclohexane, dimethyl sulfoxide, hexanol, N-methyl acetamide, and toluene are presented. We validate our approach by predicting the interfacial surface tensions (IFT--excess surface free energy per unit area) in excellent agreement with the mechanical calculations using Kirkwood-Buff theory. Additionally, we evaluate the temperature dependence of the IFT of water as described by the TIP4P/2005, SPC/Ew, TIP3P, and mW classical water models. We find that the TIP4P/2005 and SPC/Ew water models do a reasonable job of describing the interfacial thermodynamics; however, the TIP3P and mW are quite poor. We find that the underprediction of the experimental IFT at 298 K by these water models results from understructured surface molecules whose binding energies are too weak. Finally, we performed depth profiles of the interfacial thermodynamics which revealed long tails that extend far into what would be considered bulk from standard Gibbs theory. In fact, we find a nonmonotonic interfacial free energy profile for water, a unique feature that could have important consequences for the absorption of ions and other small molecules.

  8. On thermodynamic limits of entropy densities

    NARCIS (Netherlands)

    Moriya, H; Van Enter, A

    We give some sufficient conditions which guarantee that the entropy density in the thermodynamic limit is equal to the thermodynamic limit of the entropy densities of finite-volume (local) Gibbs states.

  9. Thermodynamics of asymptotically safe theories

    DEFF Research Database (Denmark)

    Rischke, Dirk H.; Sannino, Francesco

    2015-01-01

    We investigate the thermodynamic properties of a novel class of gauge-Yukawa theories that have recently been shown to be completely asymptotically safe, because their short-distance behaviour is determined by the presence of an interacting fixed point. Not only do all the coupling constants freeze...

  10. Thermodynamics of random number generation

    Science.gov (United States)

    Aghamohammadi, Cina; Crutchfield, James P.

    2017-06-01

    We analyze the thermodynamic costs of the three main approaches to generating random numbers via the recently introduced Information Processing Second Law. Given access to a specified source of randomness, a random number generator (RNG) produces samples from a desired target probability distribution. This differs from pseudorandom number generators (PRNGs) that use wholly deterministic algorithms and from true random number generators (TRNGs) in which the randomness source is a physical system. For each class, we analyze the thermodynamics of generators based on algorithms implemented as finite-state machines, as these allow for direct bounds on the required physical resources. This establishes bounds on heat dissipation and work consumption during the operation of three main classes of RNG algorithms—including those of von Neumann, Knuth, and Yao and Roche and Hoshi—and for PRNG methods. We introduce a general TRNG and determine its thermodynamic costs exactly for arbitrary target distributions. The results highlight the significant differences between the three main approaches to random number generation: One is work producing, one is work consuming, and the other is potentially dissipation neutral. Notably, TRNGs can both generate random numbers and convert thermal energy to stored work. These thermodynamic costs on information creation complement Landauer's limit on the irreducible costs of information destruction.

  11. Some Considerations about Thermodynamic Cycles

    Science.gov (United States)

    da Silva, M. F. Ferreira

    2012-01-01

    After completing their introductory studies on thermodynamics at the university level, typically in a second-year university course, most students show a number of misconceptions. In this work, we identify some of those erroneous ideas and try to explain their origins. We also give a suggestion to attack the problem through a systematic and…

  12. Thermodynamics on the Molality Scale

    Science.gov (United States)

    Canagaratna, Sebastian G.; Maheswaran, M.

    2013-01-01

    For physical measurements, the compositions of solutions, especially electrolyte solutions, are expressed in terms of molality rather than mole fractions. The development of the necessary thermodynamic equations directly in terms of molality is not common in textbooks, and the treatment in the literature is not very systematic. We develop a…

  13. One Antimatter— Two Possible Thermodynamics

    Directory of Open Access Journals (Sweden)

    Alexander Y. Klimenko

    2014-02-01

    Full Text Available Conventional thermodynamics, which is formulated for our world populated by radiation and matter, can be extended to describe physical properties of antimatter in two mutually exclusive ways: CP-invariant or CPT-invariant. Here we refer to invariance of physical laws under charge (C, parity (P and time reversal (T transformations. While in quantum field theory CPT invariance is a theorem confirmed by experiments, the symmetry principles applied to macroscopic phenomena or to the whole of the Universe represent only hypotheses. Since both versions of thermodynamics are different only in their treatment of antimatter, but are the same in describing our world dominated by matter, making a clear experimentally justified choice between CP invariance and CPT invariance in context of thermodynamics is not possible at present. This work investigates the comparative properties of the CP- and CPT-invariant extensions of thermodynamics (focusing on the latter, which is less conventional than the former and examines conditions under which these extensions can be experimentally tested.

  14. Thermodynamic basis for cluster kinetics

    DEFF Research Database (Denmark)

    Hu, Lina; Bian, Xiufang; Qin, Xubo

    2006-01-01

    Due to the inaccessibility of the supercooled region of marginal metallic glasses (MMGs) within the experimental time window, we study the cluster kinetics above the liquidus temperature, Tl, to acquire information on the fragility of the MMG systems. Thermodynamic basis for the stability...

  15. THERMODYNAMICS USED IN ENVIRONMENTAL ENGINEERING

    Science.gov (United States)

    Thermodynamics is a science in which energy transformations are studied as well as their relationships to the changes in the chemical properties of a system. It is the fundamental basis of many engineering fields. The profession of environmental engineering is no exception. In pa...

  16. A Simple Statistical Thermodynamics Experiment

    Science.gov (United States)

    LoPresto, Michael C.

    2010-01-01

    Comparing the predicted and actual rolls of combinations of both two and three dice can help to introduce many of the basic concepts of statistical thermodynamics, including multiplicity, probability, microstates, and macrostates, and demonstrate that entropy is indeed a measure of randomness, that disordered states (those of higher entropy) are…

  17. Simulating Metabolism with Statistical Thermodynamics

    Science.gov (United States)

    Cannon, William R.

    2014-01-01

    New methods are needed for large scale modeling of metabolism that predict metabolite levels and characterize the thermodynamics of individual reactions and pathways. Current approaches use either kinetic simulations, which are difficult to extend to large networks of reactions because of the need for rate constants, or flux-based methods, which have a large number of feasible solutions because they are unconstrained by the law of mass action. This report presents an alternative modeling approach based on statistical thermodynamics. The principles of this approach are demonstrated using a simple set of coupled reactions, and then the system is characterized with respect to the changes in energy, entropy, free energy, and entropy production. Finally, the physical and biochemical insights that this approach can provide for metabolism are demonstrated by application to the tricarboxylic acid (TCA) cycle of Escherichia coli. The reaction and pathway thermodynamics are evaluated and predictions are made regarding changes in concentration of TCA cycle intermediates due to 10- and 100-fold changes in the ratio of NAD+:NADH concentrations. Finally, the assumptions and caveats regarding the use of statistical thermodynamics to model non-equilibrium reactions are discussed. PMID:25089525

  18. Simulating metabolism with statistical thermodynamics.

    Science.gov (United States)

    Cannon, William R

    2014-01-01

    New methods are needed for large scale modeling of metabolism that predict metabolite levels and characterize the thermodynamics of individual reactions and pathways. Current approaches use either kinetic simulations, which are difficult to extend to large networks of reactions because of the need for rate constants, or flux-based methods, which have a large number of feasible solutions because they are unconstrained by the law of mass action. This report presents an alternative modeling approach based on statistical thermodynamics. The principles of this approach are demonstrated using a simple set of coupled reactions, and then the system is characterized with respect to the changes in energy, entropy, free energy, and entropy production. Finally, the physical and biochemical insights that this approach can provide for metabolism are demonstrated by application to the tricarboxylic acid (TCA) cycle of Escherichia coli. The reaction and pathway thermodynamics are evaluated and predictions are made regarding changes in concentration of TCA cycle intermediates due to 10- and 100-fold changes in the ratio of NAD+:NADH concentrations. Finally, the assumptions and caveats regarding the use of statistical thermodynamics to model non-equilibrium reactions are discussed.

  19. ALFALFA H I data stacking - I. Does the bulge quench ongoing star formation in early-type galaxies?

    Science.gov (United States)

    Fabello, Silvia; Catinella, Barbara; Giovanelli, Riccardo; Kauffmann, Guinevere; Haynes, Martha P.; Heckman, Timothy M.; Schiminovich, David

    2011-02-01

    We have carried out an H I stacking analysis of a volume-limited sample of ˜5000 galaxies with imaging and spectroscopic data from GALEX and the Sloan Digital Sky Survey, which lie within the current footprint of the Arecibo Legacy Fast ALFA (ALFALFA) survey. Our galaxies are selected to have stellar masses greater than 1010 M⊙ and redshifts in the range 0.025 extract a subsample of 1833 `early-type' galaxies with inclinations less than 70°, with concentration indices C > 2.6 and with light profiles that are well fit by a De Vaucouleurs model. We then stack H I line spectra extracted from the ALFALFA data cubes at the 3D positions of the galaxies from these two samples in bins of stellar mass, stellar mass surface density, central velocity dispersion and NUV-r colour. We use the stacked spectra to estimate the average H I gas fractions ?/M* of the galaxies in each bin. Our main result is that the H I content of a galaxy is not influenced by its bulge. The average H I gas fractions of galaxies in both our samples correlate most strongly with NUV-r colour and with stellar surface density. The relation between average H I fraction and these two parameters is independent of concentration index C. We have tested whether the average H I gas content of bulge-dominated galaxies on the red sequence differs from that of late-type galaxies on the red sequence. We find no evidence that galaxies with a significant bulge component are less efficient at turning their available gas reservoirs into stars. This result is in contradiction with the `morphological quenching' scenario proposed by Martig et al.

  20. Digital speckle-based stereo microscope strain measurement system for sheet metal forming by hydraulic bulge tests

    Science.gov (United States)

    Ren, Maodong; Liang, Jin; Wang, Lizhong; Wei, Bin

    2015-09-01

    A digital speckle based stereo microscope strain measurement system is developed to investigate the forming limit diagram (FLD) of miniature sheet metal under hydraulic bulge testing conditions. A stochastic speckle pattern is sprayed on the surface of the tested metal before forming. A series of images are recorded by two cameras mounted on a binocular stereo microscope during the hydroforming process. The critical major and minor strains are then calculated and plotted to construct the forming limit curve. The key technologies applied in the system are discussed in detail, including stereo microscope calibration and large deformation strain filed determination. First, considering complex optical paths and high magnification of the stereo microscope, an accurate combined distortion correction model is proposed to optimize the intrinsic and extrinsic parameters of the stereo microscope. Then, to solve the problem of strain measurement of the tested metal in large deformation situation, a large deformation measurement scheme based on deformation continuity of adjacent images is proposed. And an algorithm of limit strain determination based on spline model is proposed to calculate the critical strains at the onset of plastic instability. Finally, with our self-developed stereo microscope imaging system and sheet metal hydraulic bulging setup, FLD determination tests are conducted to validate the performance of the system. And the measured FLD is compared with the simulation results that predicted by the finite element method. The simulation and experimental results confirm that the proposed system is feasible to measure the full-field strain during the whole bulging processes and provides a better solution for forming limit diagram prediction.

  1. Astrid-2 and ground-based observations of the auroral bulge in the middle of the nightside convection throat

    Directory of Open Access Journals (Sweden)

    G. T. Marklund

    2001-06-01

    Full Text Available Results concerning the electrodynamics of the nightside auroral bulge are presented based on simultaneous satellite and ground-based observations. The satellite data include Astrid-2 measurements of electric fields, currents and particles from a midnight auroral oval crossing and Polar UVI images of the large-scale auroral distribution. The ground-based observations include STARE and SuperDARN electric fields and magnetic records from the Greenland and MIRACLE magnetometer network, the latter including stations from northern Scandinavia north to Svalbard. At the time of the Astrid-2 crossing the ground-based data reveal intense electrojet activity, both to the east and west of the Astrid-2 trajectory, related to the Polar observations of the auroral bulge but not necessarily to a typical substorm. The energetic electron fluxes measured by Astrid-2 across the auroral oval were generally weak being consistent with a gap observed in the auroral luminosity distribution. The electric field across the oval was directed westward, intensifying close to the poleward boundary followed by a decrease in the polar cap. The combined observations suggests that Astrid-2 was moving close to the separatrix between the dusk and dawn convection cells in a region of low conductivity. The constant westward direction of the electric field across the oval indicates that current continuity was maintained, not by polarisation electric fields (as in a Cowling channel, but solely by localized up- and downward field-aligned currents in good agreement with the Astrid-2 magnetometer data. The absence of a polarisation electric field and thus of an intense westward closure current between the dawn and dusk convection cells is consistent with the relatively weak precipitation and low conductivity in the convection throat. Thus, the Cowling current model is not adequate for describing the electrodynamics of the nightside auroral bulge treated here.Key words. Ionosphere (auroral

  2. Nonequilibrium thermodynamics and energy efficiency in weight loss diets

    Directory of Open Access Journals (Sweden)

    Fine Eugene J

    2007-07-01

    effect on hormone levels controls fatty acid flux and oxidation, 2 the rate of lipolysis is a primary target of insulin, postprandial, and 3 chronic carbohydrate-restricted diets reduce the levels of plasma TAG in response to a single meal. In summary, we propose that, in isocaloric diets of different macronutrient composition, there is variable flux of stored TAG controlled by the kinetic effects of insulin and other hormones. Because the fatty acid-TAG cycle never comes to equilibrium, net gain or loss is possible. The greater weight loss on carbohydrate restricted diets, popularly referred to as metabolic advantage can thus be understood in terms of the principles of nonequilibrium thermodynamics and is a consequence of the dynamic nature of bioenergetics where it is important to consider kinetic as well as thermodynamic variables.

  3. Chemical Thermodynamics and Information Theory with Applications

    CERN Document Server

    Graham, Daniel J

    2011-01-01

    Thermodynamics and information touch theory every facet of chemistry. However, the physical chemistry curriculum digested by students worldwide is still heavily skewed toward heat/work principles established more than a century ago. Rectifying this situation, Chemical Thermodynamics and Information Theory with Applications explores applications drawn from the intersection of thermodynamics and information theory--two mature and far-reaching fields. In an approach that intertwines information science and chemistry, this book covers: The informational aspects of thermodynamic state equations The

  4. Thermodynamics of statistical inference by cells.

    Science.gov (United States)

    Lang, Alex H; Fisher, Charles K; Mora, Thierry; Mehta, Pankaj

    2014-10-03

    The deep connection between thermodynamics, computation, and information is now well established both theoretically and experimentally. Here, we extend these ideas to show that thermodynamics also places fundamental constraints on statistical estimation and learning. To do so, we investigate the constraints placed by (nonequilibrium) thermodynamics on the ability of biochemical signaling networks to estimate the concentration of an external signal. We show that accuracy is limited by energy consumption, suggesting that there are fundamental thermodynamic constraints on statistical inference.

  5. Stellar photometry in the inner bulge of M31 using the Hubble Space Telescope wide field camera

    Science.gov (United States)

    Rich, R. M.; Mighell, K. J.

    1995-01-01

    We present photometry of two fields in the M31 bulge imaged with the Hubble Space Telescope (HST) Wide-Field Camara (WFC). The nuclear field (r less than 40 arcsecs = 150 pc) giant branch extends to I = 19.5, M(sub I) = -5 (Cousins system), a full 0.9 mag brighter than the giant-branch tips of metal-poor Galactic globular clusters and M31 halo fields. This is also approximately = 1.5 mag brighter than the giant branches of metal-rich Galactic globular clusters, but is no brighter than Mould's (1986) M31 bulge field 1 kpc from the nucleus. The data also suggest that the brighter stars may be preferentially concentrated to the center. The 648 luminous stars detected in 2 x 10(exp 9) solar luminosity is approximately = 25% that expected from a hypothetical population of evolved asymptotic giant branch (AGB) stars with lifetimes approximately = 10(exp 5) yr, with the cautionary note that we are near the detection limit. The number of bright stars is also consistent with the progeny of blue stragglers, if one uses a lifetime for the thermal-pulsing AGB of 2 x 10(exp 6) yr. We strongly caution that incompleteness becomes severe below I = 19.9 mag and that future surveys are likely to find numbers of bright stars too large to accomodate the blue straggler progeny hypothesis. We have imaged an additional field 2 arcmin = 500 pc south of the nucleus. The brightest stars in this field are also I = 19.5, but bright stars appear less numerous than in the nuclear field. If the population resembles that of the Galactic bulge, then M(sub bol) = -4.5 is a lower limit to the giant-branch tip luminosity; infrared studies should reveal stars 0.5 mag or more brighter. Either high-metallicity or (more likely) age approximately = 10 Gyr may be responsible for the presence of these luminous AGB stars. These observations confirm that previous ground-based infrared studies (e.g., Rich & Mould 1991) very likely detect an extended giant branch and not spurious luminous stars caused by

  6. IGR J17445-2747—Yet another X-ray burster in the galactic bulge

    Science.gov (United States)

    Mereminskiy, I. A.; Grebenev, S. A.; Sunyaev, R. A.

    2017-10-01

    The discovery of a type I X-ray burst from the faint unidentified transient source IGR J17445-2747 in the Galactic bulge by the JEM-X telescope onboard the INTEGRAL observatory is reported. Type I bursts are believed to be associated with thermonuclear explosions of accreted matter on the surface of a neutron star with a weak magnetic field in a low-mass X-ray binary. Thus, this observation allows the nature of this source to be established.

  7. THE VVV SURVEY REVEALS CLASSICAL CEPHEIDS TRACING A YOUNG AND THIN STELLAR DISK ACROSS THE GALAXY’S BULGE

    Energy Technology Data Exchange (ETDEWEB)

    Dékány, I. [Instituto Milenio de Astrofísica, Santiago (Chile); Minniti, D. [Departamento de Física, Facultad de Ciencias Exactas, Universidad Andres Bello, República 220, Santiago (Chile); Majaess, D. [Saint Mary’s University, Halifax, Nova Scotia (Canada); Zoccali, M.; Hajdu, G.; Catelan, M. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago (Chile); Alonso-García, J. [Unidad de Astronomía, Fac. Cs. Básicas, Universidad de Antofagasta, Avda. U. de Antofagasta 02800, Antofagasta (Chile); Gieren, W. [Departamento de Astronomía, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Borissova, J., E-mail: idekany@astro.puc.cl [Instituto de Física y Astronomía, Universidad de Valparaíso, Av. Gran Bretaña 1111, Valparaso (Chile)

    2015-10-20

    Solid insight into the physics of the inner Milky Way is key to understanding our Galaxy’s evolution, but extreme dust obscuration has historically hindered efforts to map the area along the Galactic mid-plane. New comprehensive near-infrared time-series photometry from the VVV Survey has revealed 35 classical Cepheids, tracing a previously unobserved component of the inner Galaxy, namely a ubiquitous inner thin disk of young stars along the Galactic mid-plane, traversing across the bulge. The discovered period (age) spread of these classical Cepheids implies a continuous supply of newly formed stars in the central region of the Galaxy over the last 100 million years.

  8. Some Trends in Quantum Thermodynamics

    Directory of Open Access Journals (Sweden)

    Michael R. von Spakovsky

    2014-06-01

    Full Text Available Traditional answers to what the 2nd Law is are well known. Some are based on the microstate of a system wandering rapidly through all accessible phase space, while others are based on the idea of a system occupying an initial multitude of states due to the inevitable imperfections of measurements that then effectively, in a coarse grained manner, grow in time (mixing. What has emerged are two somewhat less traditional approaches from which it is said that the 2nd Law emerges, namely, that of the theory of quantum open systems and that of the theory of typicality. These are the two principal approaches, which form the basis of what today has come to be called quantum thermodynamics. However, their dynamics remains strictly linear and unitary, and, as a number of recent publications have emphasized, “testing the unitary propagation of pure states alone cannot rule out a nonlinear propagation of mixtures”. Thus, a non-traditional approach to capturing such a propagation would be one which complements the postulates of QM by the 2nd Law of thermodynamics, resulting in a possibly meaningful, nonlinear dynamics. An unorthodox approach, which does just that, is intrinsic quantum thermodynamics and its mathematical framework, steepest-entropy-ascent quantum thermodynamics. The latter has evolved into an effective tool for modeling the dynamics of reactive and non-reactive systems at atomistic scales. It is the usefulness of this framework in the context of quantum thermodynamics as well as the theory of typicality which are discussed here in some detail. A brief discussion of some other trends such as those related to work, work extraction, and fluctuation theorems is also presented.

  9. The thermodynamic cube: A mnemonic and learning device for students of classical thermodynamics

    Science.gov (United States)

    Pate, Stephen F.

    1999-12-01

    The "thermodynamic cube," a mnemonic device for learning and recalling thermodynamic relations, is introduced. The cube is an extension of the familiar "thermodynamic square" seen in many textbooks. The cube reproduces the functions of the usual thermodynamic squares and incorporates the Euler relations which are not as well known.

  10. Thermodynamic magnon recoil for domain wall motion

    NARCIS (Netherlands)

    Yan, P.; Cao, Y.; Sinova, J.

    2015-01-01

    We predict a thermodynamic magnon recoil effect for domain wall motions in the presence of temperature gradients. All current thermodynamic theories assert that a magnetic domain wall must move toward the hotter side, based on equilibrium thermodynamic arguments. Microscopic calculations, on the

  11. Disc extrusions and bulges in nonspecific low back pain and sciatica: Exploratory randomised controlled trial comparing yoga therapy and normal medical treatment.

    Science.gov (United States)

    Monro, Robin; Bhardwaj, Abhishek Kumar; Gupta, Ram Kumar; Telles, Shirley; Allen, Beth; Little, Paul

    2015-01-01

    Previous trials of yoga therapy for nonspecific low back pain (nsLBP) (without sciatica) showed beneficial effects. To test effects of yoga therapy on pain and disability associated with lumbar disc extrusions and bulges. Parallel-group, randomised, controlled trial. Sixty-one adults from rural population, aged 20-45, with nsLBP or sciatica, and disc extrusions or bulges. Randomised to yoga (n=30) and control (n=31). Yoga: 3-month yoga course of group classes and home practice, designed to ensure safety for disc extrusions. normal medical care. OUTCOME MEASURES (3-4 months) Primary: Roland Morris Disability Questionnaire (RMDQ); worst pain in past two weeks. Secondary: Aberdeen Low Back Pain Scale; straight leg raise test; structural changes. Disc projections per case ranged from one bulge or one extrusion to three bulges plus two extrusions. Sixty-two percent had sciatica. Intention-to-treat analysis of the RMDQ data, adjusted for age, sex and baseline RMDQ scores, gave a Yoga Group score 3.29 points lower than Control Group (0.98, 5.61; p=0.006) at 3 months. No other significant differences in the endpoints occurred. No adverse effects of yoga were reported. Yoga therapy can be safe and beneficial for patients with nsLBP or sciatica, accompanied by disc extrusions and bulges.

  12. Bioengineering Thermodynamics: An Engineering Science for Thermodynamics of Biosystems

    OpenAIRE

    Lucia, Umberto

    2015-01-01

    Cells are open complex thermodynamic systems. Energy transformations, thermo-electro-chemical processes and transports occur across the cells membranes. Different thermo-electro-biochemical behaviours occur between health and disease states. Moreover, living systems waste heat, the result of the internal irreversibility. This heat is dissipated into the environment. But, this wasted heat represent a sort of information, which outflows from the cell toward its environment, completely accessibl...

  13. Inclusive single particle spectra and the strong thermodynamic bootstrap solution

    CERN Document Server

    Hagedorn, Rolf

    1972-01-01

    The thermodynamical model was based so far on a bootstrap condition requiring asymptotic equality of the logarithms of the hadronic mass spectrum and of the level density of the fireballs, resulting in a family of exponential solutions, of which one was chosen on the basis of plausibility arguments. Through the work of Frautschi (1971), Frautschi and Hamer (1971) and of Nahm (1972), the bootstrap condition has been sharpened and now leads to a unique asymptotic solution slightly different from the one chosen before. The authors discuss in this paper the consequences of using this strong bootstrap solution in the thermodynamical model for particle production. If all other assumptions remain unmodified, the following changes occur: the decay chain of fireball becomes approximately manageable and is included in the analysis; scaling and limiting fragmentation hold exactly; the rapidity distribution has a central plateau; and multiplicities grow logarithmically. Numerical differences against the old version are, ...

  14. Water in the physiology of plant: thermodynamics and kinetic

    Directory of Open Access Journals (Sweden)

    Maurizio Cocucci

    2011-02-01

    Full Text Available Molecular properties of water molecule determine its role in plant physiology. At molecular level the properties of water molecules determine the behaviour of other plant molecules; in particular its physic characteristics are important in the operativeness of macromolecules and in plant thermoregulation. Plant water supply primarily dependent on thermodynamics properties in particular water chemical potential and its components, more recently there are evidences that suggest an important role in the water kinetic characteristics, depending, at cell membrane level, in particular plasmalemma, on the presence of specific water channel, the aquaporines controlled in its activity by a number of physiological and biochemical factors. Thermodynamics and kinetic factors controlled by physiological, biochemical properties and molecular effectors, control water supply and level in plants to realize their survival, growth and differentiation and the consequent plant production.

  15. Classical thermodynamics of non-electrolyte solutions

    CERN Document Server

    Van Ness, H C

    1964-01-01

    Classical Thermodynamics of Non-Electrolyte Solutions covers the historical development of classical thermodynamics that concerns the properties of vapor and liquid solutions of non-electrolytes. Classical thermodynamics is a network of equations, developed through the formal logic of mathematics from a very few fundamental postulates and leading to a great variety of useful deductions. This book is composed of seven chapters and begins with discussions on the fundamentals of thermodynamics and the thermodynamic properties of fluids. The succeeding chapter presents the equations of state for

  16. Supermassive black holes in disc-dominated galaxies outgrow their bulges and co-evolve with their host galaxies

    Science.gov (United States)

    Simmons, B. D.; Smethurst, R. J.; Lintott, C.

    2017-09-01

    The deep connection between galaxies and their supermassive black holes is central to modern astrophysics and cosmology. The observed correlation between galaxy and black hole mass is usually attributed to the contribution of major mergers to both. We make use of a sample of galaxies whose disc-dominated morphologies indicate a major-merger-free history and show that such systems are capable of growing supermassive black holes at rates similar to quasars. Comparing black hole masses to conservative upper limits on bulge masses, we show that the black holes in the sample are typically larger than expected if processes creating bulges are also the primary driver of black hole growth. The same relation between black hole and total stellar mass of the galaxy is found for the merger-free sample as well as a sample that has experienced substantial mergers, indicating that major mergers do not play a significant role in controlling the co-evolution of galaxies and black holes. We suggest that more fundamental processes that contribute to galaxy assembly are also responsible for black hole growth.

  17. Signatures of Solvation Thermodynamics in Spectra of Intermolecular Vibrations

    Science.gov (United States)

    2017-01-01

    This study explores the thermodynamic and vibrational properties of water in the three-dimensional environment of solvated ions and small molecules using molecular simulations. The spectrum of intermolecular vibrations in liquid solvents provides detailed information on the shape of the local potential energy surface, which in turn determines local thermodynamic properties such as the entropy. Here, we extract this information using a spatially resolved extension of the two-phase thermodynamics method to estimate hydration water entropies based on the local vibrational density of states (3D-2PT). Combined with an analysis of solute–water and water–water interaction energies, this allows us to resolve local contributions to the solvation enthalpy, entropy, and free energy. We use this approach to study effects of ions on their surrounding water hydrogen bond network, its spectrum of intermolecular vibrations, and resulting thermodynamic properties. In the three-dimensional environment of polar and nonpolar functional groups of molecular solutes, we identify distinct hydration water species and classify them by their characteristic vibrational density of states and molecular entropies. In each case, we are able to assign variations in local hydration water entropies to specific changes in the spectrum of intermolecular vibrations. This provides an important link for the thermodynamic interpretation of vibrational spectra that are accessible to far-infrared absorption and Raman spectroscopy experiments. Our analysis provides unique microscopic details regarding the hydration of hydrophobic and hydrophilic functional groups, which enable us to identify interactions and molecular degrees of freedom that determine relevant contributions to the solvation entropy and consequently the free energy. PMID:28783431

  18. Signatures of Solvation Thermodynamics in Spectra of Intermolecular Vibrations.

    Science.gov (United States)

    Persson, Rasmus A X; Pattni, Viren; Singh, Anurag; Kast, Stefan M; Heyden, Matthias

    2017-09-12

    This study explores the thermodynamic and vibrational properties of water in the three-dimensional environment of solvated ions and small molecules using molecular simulations. The spectrum of intermolecular vibrations in liquid solvents provides detailed information on the shape of the local potential energy surface, which in turn determines local thermodynamic properties such as the entropy. Here, we extract this information using a spatially resolved extension of the two-phase thermodynamics method to estimate hydration water entropies based on the local vibrational density of states (3D-2PT). Combined with an analysis of solute-water and water-water interaction energies, this allows us to resolve local contributions to the solvation enthalpy, entropy, and free energy. We use this approach to study effects of ions on their surrounding water hydrogen bond network, its spectrum of intermolecular vibrations, and resulting thermodynamic properties. In the three-dimensional environment of polar and nonpolar functional groups of molecular solutes, we identify distinct hydration water species and classify them by their characteristic vibrational density of states and molecular entropies. In each case, we are able to assign variations in local hydration water entropies to specific changes in the spectrum of intermolecular vibrations. This provides an important link for the thermodynamic interpretation of vibrational spectra that are accessible to far-infrared absorption and Raman spectroscopy experiments. Our analysis provides unique microscopic details regarding the hydration of hydrophobic and hydrophilic functional groups, which enable us to identify interactions and molecular degrees of freedom that determine relevant contributions to the solvation entropy and consequently the free energy.

  19. Chemical evolution of fluorine in the bulge. High-resolution K-band spectra of giants in three fields

    Science.gov (United States)

    Jönsson, H.; Ryde, N.; Harper, G. M.; Cunha, K.; Schultheis, M.; Eriksson, K.; Kobayashi, C.; Smith, V. V.; Zoccali, M.

    2014-04-01

    Context. Possible main formation sites of fluorine in the Universe include asymptotic giant branch (AGB) stars, the ν-process in Type II supernova, and/or Wolf-Rayet stars. The importance of the Wolf-Rayet stars has theoretically been questioned and they are probably not needed in modeling the chemical evolution of fluorine in the solar neighborhood. It has, however, been suggested that Wolf-Rayet stars are indeed needed to explain the chemical evolution of fluorine in the bulge. The molecular spectral data, needed to determine the fluorine abundance, of the often used HF-molecule has not been presented in a complete and consistent way and has recently been debated in the literature. Aims: We intend to determine the trend of the fluorine-oxygen abundance ratio as a function of a metallicity indicator in the bulge to investigate the possible contribution from Wolf-Rayet stars. Additionally, we present here a consistent HF line list for the K- and L-bands including the often used 23 358.33 Å line. Methods: High-resolution near-infrared spectra of eight K giants were recorded using the spectrograph CRIRES mounted at the VLT. A standard setting was used that covered the HF molecular line at 23 358.33 Å. The fluorine abundances were determined using spectral fitting. We also re-analyzed five previously published bulge giants observed with the Phoenix spectrograph on Gemini using our new HF molecular data. Results: We find that the fluorine-oxygen abundance in the bulge probably cannot be explained with chemical evolution models that only include AGB stars and the ν-process in supernovae Type II, that is a significant amount of fluorine production in Wolf-Rayet stars is most likely needed to explain the fluorine abundance in the bulge. For the HF line data, we find that a possible reason for the inconsistencies in the literature, where two different excitation energies were used, is two different definitions of the zero-point energy for the HF molecule and therefore

  20. Thermodynamic constraints on fluctuation phenomena

    Science.gov (United States)

    Maroney, O. J. E.

    2009-12-01

    The relationships among reversible Carnot cycles, the absence of perpetual motion machines, and the existence of a nondecreasing globally unique entropy function form the starting point of many textbook presentations of the foundations of thermodynamics. However, the thermal fluctuation phenomena associated with statistical mechanics has been argued to restrict the domain of validity of this basis of the second law of thermodynamics. Here we demonstrate that fluctuation phenomena can be incorporated into the traditional presentation, extending rather than restricting the domain of validity of the phenomenologically motivated second law. Consistency conditions lead to constraints upon the possible spectrum of thermal fluctuations. In a special case this uniquely selects the Gibbs canonical distribution and more generally incorporates the Tsallis distributions. No particular model of microscopic dynamics need be assumed.

  1. Gravity and/is Thermodynamics

    CERN Document Server

    Padmanabhan, T

    2015-01-01

    The equations of motion describing all physical systems, except gravity, remain invariant if a constant is added to the Lagrangian. In the conventional approach, gravitational theories break this symmetry exhibited by all other physical systems. Restoring this symmetry to gravity and demanding that gravitational field equations should also remain invariant under the addition of a constant to a Lagrangian, leads to the interpretation of gravity as the thermodynamic limit of the kinetic theory of atoms of space. This approach selects, in a very natural fashion, Einstein's general relativity in $d=4$. Developing this paradigm at a deeper level, one can obtain the distribution function for the atoms of space and connect it up with the thermodynamic description of spacetime. This extension relies on a curious fact that the quantum spacetime endows each event with a finite area but zero volume. This approach allows us determine the numerical value of the cosmological constant and suggests a new perspective on cosmo...

  2. Thermodynamic Measure for Nonequilibrium Processes

    Directory of Open Access Journals (Sweden)

    Attila Grandpierre

    2007-07-01

    Full Text Available One of the most fundamental laws of Nature is formulated by the Second Law of Thermodynamics. At present, in its usual formulation the central concept is entropy characterized in terms of equilibrium state variables. We point out that because thermodynamic changes arise when systems are out of equilibrium and because entropy is not a natural state variable characterizing non-equilibrium states, a new formulation of the Second Law is required. In this paper, we introduce a new, more general, but still entropic measure that is suitable in non-equilibrium conditions as well. This new entropic measure has given a name extropy. The introduction of extropy allows us to formulate the Second Law in a more suitable and precise form, and it resolves some conceptual difficulties related to the interpretation of entropy. We point out that extropy has a fundamental significance in physics, in biology, and in our scientific worldview.

  3. Thermodynamic Model of Spatial Memory

    Science.gov (United States)

    Kaufman, Miron; Allen, P.

    1998-03-01

    We develop and test a thermodynamic model of spatial memory. Our model is an application of statistical thermodynamics to cognitive science. It is related to applications of the statistical mechanics framework in parallel distributed processes research. Our macroscopic model allows us to evaluate an entropy associated with spatial memory tasks. We find that older adults exhibit higher levels of entropy than younger adults. Thurstone's Law of Categorical Judgment, according to which the discriminal processes along the psychological continuum produced by presentations of a single stimulus are normally distributed, is explained by using a Hooke spring model of spatial memory. We have also analyzed a nonlinear modification of the ideal spring model of spatial memory. This work is supported by NIH/NIA grant AG09282-06.

  4. Thermodynamic Calculations for Systems Biocatalysis

    DEFF Research Database (Denmark)

    Abu, Rohana; Gundersen, Maria T.; Woodley, John M.

    2015-01-01

    ‘Systems Biocatalysis’ is a term describing multi-enzyme processes in vitro for the synthesis of chemical products. Unlike in-vivo systems, such an artificial metabolism can be controlled in a highly efficient way in order to achieve a sufficiently favourable conversion for a given target product...... the transamination of a pro-chiral ketone into a chiral amine (interesting in many pharmaceutical applications). Here, the products are often less energetically stable than the reactants, meaning that the reaction may be thermodynamically unfavourable. As in nature, such thermodynamically-challenged reactions can...... energy change, View the MathML source ΔGro′, of the overall cascade. The findings show that unfavourable reactions in the cascade can be improved by coupling to a favourable reaction giving more energetically stable products....

  5. Statistical Thermodynamics of Economic Systems

    Directory of Open Access Journals (Sweden)

    Hernando Quevedo

    2011-01-01

    Full Text Available We formulate the thermodynamics of economic systems in terms of an arbitrary probability distribution for a conserved economic quantity. As in statistical physics, thermodynamic macroeconomic variables emerge as the mean value of microeconomic variables, and their determination is reduced to the computation of the partition function, starting from an arbitrary function. Explicit hypothetical examples are given which include linear and nonlinear economic systems as well as multiplicative systems such as those dominated by a Pareto law distribution. It is shown that the macroeconomic variables can be drastically changed by choosing the microeconomic variables in an appropriate manner. We propose to use the formalism of phase transitions to study severe changes of macroeconomic variables.

  6. Statistical thermodynamics of nonequilibrium processes

    CERN Document Server

    Keizer, Joel

    1987-01-01

    The structure of the theory ofthermodynamics has changed enormously since its inception in the middle of the nineteenth century. Shortly after Thomson and Clausius enunciated their versions of the Second Law, Clausius, Maxwell, and Boltzmann began actively pursuing the molecular basis of thermo­ dynamics, work that culminated in the Boltzmann equation and the theory of transport processes in dilute gases. Much later, Onsager undertook the elucidation of the symmetry oftransport coefficients and, thereby, established himself as the father of the theory of nonequilibrium thermodynamics. Com­ bining the statistical ideas of Gibbs and Langevin with the phenomenological transport equations, Onsager and others went on to develop a consistent statistical theory of irreversible processes. The power of that theory is in its ability to relate measurable quantities, such as transport coefficients and thermodynamic derivatives, to the results of experimental measurements. As powerful as that theory is, it is linear and...

  7. Fundamentals of Nano-Thermodynamics

    OpenAIRE

    Hartmann, M.; Mahler, G.; Hess, O.

    2004-01-01

    Recent progress in the synthesis and processing of nano-structured materials and systems calls for an improved understanding of thermal properties on small length scales. In this context, the question whether thermodynamics and, in particular, the concept of temperature can apply on the nanoscale is of central interest. Here we consider a quantum system consisting of a regular chain of elementary subsystems with nearest neighbour interactions and assume that the total system is in a canonical...

  8. Thermodynamics of freezing and melting

    OpenAIRE

    Pedersen, Ulf Rørbæk; Costigliola, Lorenzo; Bailey, Nicholas; Schrøder, Thomas; Dyre, Jeppe C.

    2016-01-01

    Although the freezing of liquids and melting of crystals are fundamental for many areas of the sciences, even simple properties like the temperature?pressure relation along the melting line cannot be predicted today. Here we present a theory in which properties of the coexisting crystal and liquid phases at a single thermodynamic state point provide the basis for calculating the pressure, density and entropy of fusion as functions of temperature along the melting line, as well as the variatio...

  9. Thermodynamic properties of sea air

    Directory of Open Access Journals (Sweden)

    R. Feistel

    2010-02-01

    Full Text Available Very accurate thermodynamic potential functions are available for fluid water, ice, seawater and humid air covering wide ranges of temperature and pressure conditions. They permit the consistent computation of all equilibrium properties as, for example, required for coupled atmosphere-ocean models or the analysis of observational or experimental data. With the exception of humid air, these potential functions are already formulated as international standards released by the International Association for the Properties of Water and Steam (IAPWS, and have been adopted in 2009 for oceanography by IOC/UNESCO.

    In this paper, we derive a collection of formulas for important quantities expressed in terms of the thermodynamic potentials, valid for typical phase transitions and composite systems of humid air and water/ice/seawater. Particular attention is given to equilibria between seawater and humid air, referred to as "sea air" here. In a related initiative, these formulas will soon be implemented in a source-code library for easy practical use. The library is primarily aimed at oceanographic applications but will be relevant to air-sea interaction and meteorology as well.

    The formulas provided are valid for any consistent set of suitable thermodynamic potential functions. Here we adopt potential functions from previous publications in which they are constructed from theoretical laws and empirical data; they are briefly summarized in the appendix. The formulas make use of the full accuracy of these thermodynamic potentials, without additional approximations or empirical coefficients. They are expressed in the temperature scale ITS-90 and the 2008 Reference-Composition Salinity Scale.

  10. Chiral thermodynamics of nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Fiorilla, Salvatore

    2012-10-23

    The equation of state of nuclear matter is calculated at finite temperature in the framework of in-medium chiral perturbation theory up to three-loop order. The dependence of its thermodynamic properties on the isospin-asymmetry is investigated. The chiral quark condensate is evaluated for symmetric nuclear matter. Its behaviour as a function of density and temperature sets important nuclear physics constraints for the QCD phase diagram.

  11. Thermodynamic aspects of therapeutic hypothermia.

    Science.gov (United States)

    Vanlandingham, Sean C; Kurz, Michael C; Wang, Henry E

    2015-01-01

    Therapeutic hypothermia (TH) is an important treatment for post-cardiac arrest syndrome. Despite its widespread practice, only limited data describe the thermodynamic aspects of heat transfer during TH. This paper reviews the principles of human body heat balance and provides a conceptual model for characterizing heat exchange during TH. The model may provide a framework for computer simulation for improving training in or clinical methods of TH. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. The Thermodynamics of Exercise Science

    OpenAIRE

    Simeoni, R. J.

    2014-01-01

    This article describes the “human body engine” via a thermodynamics-based model that considers the work associated with gas pressure, volume and temperature changes for the glucose-based equation of respiration. The efficacy of the model is supported by prior studies that: accurately predict the slow component of oxygen uptake kinetics; quantitatively explain observed race splitting strategies within endurance events; and accurately predict maximum velocities in endurance swimming. These pr...

  13. Thermodynamic functions of arsenic selenides

    Science.gov (United States)

    Babanly, D. M.; Velieva, G. M.; Imamaliyeva, S. Z.; Babanly, M. B.

    2017-07-01

    The solid-phase equilibria and thermodynamic properties of an As-Se system are studied using the electromotive force (EMF). The existence of compounds As2Se3, AsSe, and As4Se3 in a system with near constant composition is confirmed. The relative partial molar functions, standard Gibbs free energies, enthalpies of formation, and standard entropies of As in the alloys are calculated using EMF measurements.

  14. Hadron melting and QCD thermodynamics

    OpenAIRE

    Jakovac, A.

    2013-01-01

    We study in this paper mechanisms of hadron melting based on the spectral representation of hadronic quantum channels, and examine the hadron width dependence of the pressure. The findings are applied to a statistical hadron model of QCD thermodynamics, where hadron masses are distributed by the Hagedorn model and a uniform mechanism for producing hadron widths is assumed. According to this model the hadron - quark gluon plasma transition occurs at $T\\approx 200$-250 MeV, the numerically obse...

  15. Predicting RNA pseudoknot folding thermodynamics

    Science.gov (United States)

    Cao, Song; Chen, Shi-Jie

    2006-01-01

    Based on the experimentally determined atomic coordinates for RNA helices and the self-avoiding walks of the P (phosphate) and C4 (carbon) atoms in the diamond lattice for the polynucleotide loop conformations, we derive a set of conformational entropy parameters for RNA pseudoknots. Based on the entropy parameters, we develop a folding thermodynamics model that enables us to compute the sequence-specific RNA pseudoknot folding free energy landscape and thermodynamics. The model is validated through extensive experimental tests both for the native structures and for the folding thermodynamics. The model predicts strong sequence-dependent helix-loop competitions in the pseudoknot stability and the resultant conformational switches between different hairpin and pseudoknot structures. For instance, for the pseudoknot domain of human telomerase RNA, a native-like and a misfolded hairpin intermediates are found to coexist on the (equilibrium) folding pathways, and the interplay between the stabilities of these intermediates causes the conformational switch that may underlie a human telomerase disease. PMID:16709732

  16. The Star-forming Histories of the Nucleus, Bulge, and Inner Disk of NGC 5102: Clues to the Evolution of a Nearby Lenticular Galaxy

    Science.gov (United States)

    Davidge, T. J.

    2015-01-01

    Long slit spectra recorded with the Gemini Multi-Object Spectrograph on Gemini South are used to examine the star-forming history (SFH) of the lenticular galaxy NGC 5102. Structural and supplemental photometric information are obtained from archival Spitzer [3.6] images. Absorption features at blue and visible wavelengths are traced out along the minor axis to galactocentric radii ~60 arcsec (~0.9 kpc), sampling the nucleus, bulge, and disk components. Comparisons with model spectra point to luminosity-weighted metallicities that are consistent with the colors of resolved red giant branch stars in the disk. The nucleus has a luminosity-weighted age at visible wavelengths of {˜ } 1+0.2-0.1 Gyr, and the integrated light is dominated by stars that formed over a time period of only a few hundred Myr. For comparison, the luminosity-weighted ages of the bulge and disk are {˜ } 2+0.5-0.2 Gyr and 10+2-2 Gyr, respectively. The g' - [3.6] colors of the nucleus and bulge are consistent with the spectroscopically based ages. In contrast to the nucleus, models that assume star-forming activity spanning many Gyr provide a better match to the spectra of the bulge and disk than simple stellar population models. Isophotes in the bulge have a disky shape, hinting that the bulge was assembled from material with significant rotational support. The SFHs of the bulge and disk are consistent with the bulge forming from the collapse of a long-lived bar, rather than from the collapse of a transient structure that formed as the result of a tidal interaction. It is thus suggested that the progenitor of NGC 5102 was a barred disk galaxy that morphed into a lenticular galaxy through the buckling of its bar. This research has made use of the NASA/IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  17. Thermodynamic studies for drug design and screening.

    Science.gov (United States)

    Garbett, Nichola C; Chaires, Jonathan B

    2012-04-01

    A key part of drug design and development is the optimization of molecular interactions between an engineered drug candidate and its binding target. Thermodynamic characterization provides information about the balance of energetic forces driving binding interactions and is essential for understanding and optimizing molecular interactions. This review discusses the information that can be obtained from thermodynamic measurements and how this can be applied to the drug development process. Current approaches for the measurement and optimization of thermodynamic parameters are presented, specifically higher throughput and calorimetric methods. Relevant literature for this review was identified in part by bibliographic searches for the period 2004 - 2011 using the Science Citation Index and PUBMED and the keywords listed below. The most effective drug design and development platform comes from an integrated process utilizing all available information from structural, thermodynamic and biological studies. Continuing evolution in our understanding of the energetic basis of molecular interactions and advances in thermodynamic methods for widespread application are essential to realize the goal of thermodynamically driven drug design. Comprehensive thermodynamic evaluation is vital early in the drug development process to speed drug development toward an optimal energetic interaction profile while retaining good pharmacological properties. Practical thermodynamic approaches, such as enthalpic optimization, thermodynamic optimization plots and the enthalpic efficiency index, have now matured to provide proven utility in the design process. Improved throughput in calorimetric methods remains essential for even greater integration of thermodynamics into drug design. © 2012 Informa UK, Ltd.

  18. Thermodynamic Studies for Drug Design and Screening

    Science.gov (United States)

    Garbett, Nichola C.; Chaires, Jonathan B.

    2012-01-01

    Introduction A key part of drug design and development is the optimization of molecular interactions between an engineered drug candidate and its binding target. Thermodynamic characterization provides information about the balance of energetic forces driving binding interactions and is essential for understanding and optimizing molecular interactions. Areas covered This review discusses the information that can be obtained from thermodynamic measurements and how this can be applied to the drug development process. Current approaches for the measurement and optimization of thermodynamic parameters are presented, specifically higher throughput and calorimetric methods. Relevant literature for this review was identified in part by bibliographic searches for the period 2004 – 2011 using the Science Citation Index and PUBMED and the keywords listed below. Expert opinion The most effective drug design and development platform comes from an integrated process utilizing all available information from structural, thermodynamic and biological studies. Continuing evolution in our understanding of the energetic basis of molecular interactions and advances in thermodynamic methods for widespread application are essential to realize the goal of thermodynamically-driven drug design. Comprehensive thermodynamic evaluation is vital early in the drug development process to speed drug development towards an optimal energetic interaction profile while retaining good pharmacological properties. Practical thermodynamic approaches, such as enthalpic optimization, thermodynamic optimization plots and the enthalpic efficiency index, have now matured to provide proven utility in design process. Improved throughput in calorimetric methods remains essential for even greater integration of thermodynamics into drug design. PMID:22458502

  19. Consequences of change and variability in sea ice on marine ecosystem and biogeochemical processes during the 2007-2008 Canadian International Polar Year program

    OpenAIRE

    Barber, D.G.; Asplin, M.G.; Papakyriakou, T.N.; Miller, L.; Else, B.G.T.; Iacozza, J.; Mundy, C.J.; Gosslin, M.; Asselin, N.C.; Ferguson, S.; Lukovich, J.V.; Stern, G.A.; Gaden, A.; Pucko, M.; Geilfus, N.-X.

    2012-01-01

    Change and variability in the timing and magnitude of sea ice geophysical and thermodynamic state have consequences on many aspects of the arctic marine system. The changes in both the geophysical and thermodynamic state, and in particular the timing of the development of these states, have consequences throughout the marine system. In this paper we review the 'consequences' of change in sea ice state on primary productivity, marine mammal habitats, and sea ice as a medium for storage and tra...

  20. The consequences of piracy

    OpenAIRE

    Schroth, Christoph

    2017-01-01

    Maritime piracy decreased significantly around 2012, but recently made the news again. What are the wider consequences of piracy and what is being done on an international level to protect this important transportation sector?

  1. Semiclassical Loop Quantum Gravity and Black Hole Thermodynamics

    Directory of Open Access Journals (Sweden)

    Arundhati Dasgupta

    2013-02-01

    Full Text Available In this article we explore the origin of black hole thermodynamics using semiclassical states in loop quantum gravity. We re-examine the case of entropy using a density matrix for a coherent state and describe correlations across the horizon due to SU(2 intertwiners. We further show that Hawking radiation is a consequence of a non-Hermitian term in the evolution operator, which is necessary for entropy production or depletion at the horizon. This non-unitary evolution is also rooted in formulations of irreversible physics.

  2. Thermodynamics for Chemists, Physicists and Engineers

    CERN Document Server

    Hołyst, Robert

    2012-01-01

    Thermodynamics is an essential part of chemical physics and is of fundamental importance in physics, chemistry and engineering courses. This textbook takes an interdisciplinary approach to the subject and is therefore suitable for undergraduates in all those courses. The book is an introduction to phenomenological thermodynamics and its applications to phase transitions and chemical reactions, with some references to statistical mechanics. It strikes the balance between the rigorousness of the Callen text and phenomenological approach of the Atkins text. The book is divided in three parts. The first introduces the postulates and laws of thermodynamics and complements these initial explanations with practical examples. The second part is devoted to applications of thermodynamics to phase transitions in pure substances and mixtures. The third part covers thermodynamic systems in which chemical reactions take place. There are some sections on more advanced topics such as thermodynamic potentials, natural variabl...

  3. Thermodynamics of random reaction networks.

    Directory of Open Access Journals (Sweden)

    Jakob Fischer

    Full Text Available Reaction networks are useful for analyzing reaction systems occurring in chemistry, systems biology, or Earth system science. Despite the importance of thermodynamic disequilibrium for many of those systems, the general thermodynamic properties of reaction networks are poorly understood. To circumvent the problem of sparse thermodynamic data, we generate artificial reaction networks and investigate their non-equilibrium steady state for various boundary fluxes. We generate linear and nonlinear networks using four different complex network models (Erdős-Rényi, Barabási-Albert, Watts-Strogatz, Pan-Sinha and compare their topological properties with real reaction networks. For similar boundary conditions the steady state flow through the linear networks is about one order of magnitude higher than the flow through comparable nonlinear networks. In all networks, the flow decreases with the distance between the inflow and outflow boundary species, with Watts-Strogatz networks showing a significantly smaller slope compared to the three other network types. The distribution of entropy production of the individual reactions inside the network follows a power law in the intermediate region with an exponent of circa -1.5 for linear and -1.66 for nonlinear networks. An elevated entropy production rate is found in reactions associated with weakly connected species. This effect is stronger in nonlinear networks than in the linear ones. Increasing the flow through the nonlinear networks also increases the number of cycles and leads to a narrower distribution of chemical potentials. We conclude that the relation between distribution of dissipation, network topology and strength of disequilibrium is nontrivial and can be studied systematically by artificial reaction networks.

  4. Thermodynamics of Random Reaction Networks

    Science.gov (United States)

    Fischer, Jakob; Kleidon, Axel; Dittrich, Peter

    2015-01-01

    Reaction networks are useful for analyzing reaction systems occurring in chemistry, systems biology, or Earth system science. Despite the importance of thermodynamic disequilibrium for many of those systems, the general thermodynamic properties of reaction networks are poorly understood. To circumvent the problem of sparse thermodynamic data, we generate artificial reaction networks and investigate their non-equilibrium steady state for various boundary fluxes. We generate linear and nonlinear networks using four different complex network models (Erdős-Rényi, Barabási-Albert, Watts-Strogatz, Pan-Sinha) and compare their topological properties with real reaction networks. For similar boundary conditions the steady state flow through the linear networks is about one order of magnitude higher than the flow through comparable nonlinear networks. In all networks, the flow decreases with the distance between the inflow and outflow boundary species, with Watts-Strogatz networks showing a significantly smaller slope compared to the three other network types. The distribution of entropy production of the individual reactions inside the network follows a power law in the intermediate region with an exponent of circa −1.5 for linear and −1.66 for nonlinear networks. An elevated entropy production rate is found in reactions associated with weakly connected species. This effect is stronger in nonlinear networks than in the linear ones. Increasing the flow through the nonlinear networks also increases the number of cycles and leads to a narrower distribution of chemical potentials. We conclude that the relation between distribution of dissipation, network topology and strength of disequilibrium is nontrivial and can be studied systematically by artificial reaction networks. PMID:25723751

  5. Galaxy evolution. Evidence for mature bulges and an inside-out quenching phase 3 billion years after the Big Bang.

    Science.gov (United States)

    Tacchella, S; Carollo, C M; Renzini, A; Förster Schreiber, N M; Lang, P; Wuyts, S; Cresci, G; Dekel, A; Genzel, R; Lilly, S J; Mancini, C; Newman, S; Onodera, M; Shapley, A; Tacconi, L; Woo, J; Zamorani, G

    2015-04-17

    Most present-day galaxies with stellar masses ≥10(11) solar masses show no ongoing star formation and are dense spheroids. Ten billion years ago, similarly massive galaxies were typically forming stars at rates of hundreds solar masses per year. It is debated how star formation ceased, on which time scales, and how this "quenching" relates to the emergence of dense spheroids. We measured stellar mass and star-formation rate surface density distributions in star-forming galaxies at redshift 2.2 with ~1-kiloparsec resolution. We find that, in the most massive galaxies, star formation is quenched from the inside out, on time scales less than 1 billion years in the inner regions, up to a few billion years in the outer disks. These galaxies sustain high star-formation activity at large radii, while hosting fully grown and already quenched bulges in their cores. Copyright © 2015, American Association for the Advancement of Science.

  6. Patch bulging after plaque incision and grafting procedure for Peyronie’s disease. Surgical repair with a collagen fleece

    Directory of Open Access Journals (Sweden)

    Andrea Fabiani

    2015-07-01

    Full Text Available The incision/excision and grafting techniques (PIG for surgical therapy of Peyronie’s disease (PD have gained popularity in recent years. Several different graft materials have been used but the ideal graft has yet to be established. The use of grafting materials could cause complications. In the daily clinical practice it will always be more frequent to manage complications arising from their use. We present herein the case of a patch bulging repaired with a ready-to-use collagen fleece (Tachosil®, Takeda, Linz, Austria, Europe in a 61 years old man subjected to intervention of geometric corporoplasty with Paulo Egydio technique using an acellular collagen material (Xenform® patch, Boston Scientific, Natick, MA, USA as graft. We also discuss the possible implications of PIG procedure.

  7. Thermodynamics of freezing and melting

    DEFF Research Database (Denmark)

    Pedersen, Ulf Rørbæk; Costigliola, Lorenzo; Bailey, Nicholas

    2016-01-01

    Although the freezing of liquids and melting of crystals are fundamental for many areas of the sciences, even simple properties like the temperature–pressure relation along the melting line cannot be predicted today. Here we present a theory in which properties of the coexisting crystal and liquid...... phases at a single thermodynamic state point provide the basis for calculating the pressure, density and entropy of fusion as functions of temperature along the melting line, as well as the variation along this line of the reduced crystalline vibrational mean-square displacement (the Lindemann ratio...

  8. Thermodynamics of the hot BIon

    DEFF Research Database (Denmark)

    Grignani, Gianluca; Harmark, Troels; Marini, Andrea

    2011-01-01

    We investigate the thermodynamics of the recently obtained nite temperature BIon solution of arXiv:1012.1494, focusing on two aspects. The first concerns comparison of the free energy of the three available phases for the finite temperature brane-antibrane wormhole configuration. Based on this we...... propose a heuristic picture for the dynamics of the phases that involves a critical temperature below which a stable phase exists. This stable phase is the finite temperature analogue of the thin throat branch of the extremal brane anti-brane wormhole configuration. The second aspect that we consider...

  9. An introduction to statistical thermodynamics

    CERN Document Server

    Hill, Terrell L

    1987-01-01

    ""A large number of exercises of a broad range of difficulty make this book even more useful…a good addition to the literature on thermodynamics at the undergraduate level."" - Philosophical MagazineAlthough written on an introductory level, this wide-ranging text provides extensive coverage of topics of current interest in equilibrium statistical mechanics. Indeed, certain traditional topics are given somewhat condensed treatment to allow room for a survey of more recent advances.The book is divided into four major sections. Part I deals with the principles of quantum statistical mechanics a

  10. Thermal physics kinetic theory and thermodynamics

    CERN Document Server

    Singh, Devraj; Yadav, Raja Ram

    2016-01-01

    THERMAL PHYSICS: Kinetic Theory and Thermodynamics is designed for undergraduate course in Thermal Physics and Thermodynamics. The book provides thorough understanding of the fundamental principles of the concepts in Thermal Physics. The book begins with kinetic theory, then moves on liquefaction, transport phenomena, the zeroth, first, second and third laws, thermodynamics relations and thermal conduction. The book concluded with radiation phenomenon. KEY FEATURES: * Include exercises * Short Answer Type Questions * Long Answer Type Questions * Numerical Problems * Multiple Choice Questions

  11. Quantum Thermodynamics with Degenerate Eigenstate Coherences

    Directory of Open Access Journals (Sweden)

    Gregory Bulnes Cuetara

    2016-12-01

    Full Text Available We establish quantum thermodynamics for open quantum systems weakly coupled to their reservoirs when the system exhibits degeneracies. The first and second law of thermodynamics are derived, as well as a finite-time fluctuation theorem for mechanical work and energy and matter currents. Using a double quantum dot junction model, local eigenbasis coherences are shown to play a crucial role on thermodynamics and on the electron counting statistics.

  12. Quantum thermodynamics: a nonequilibrium Green's function approach.

    Science.gov (United States)

    Esposito, Massimiliano; Ochoa, Maicol A; Galperin, Michael

    2015-02-27

    We establish the foundations of a nonequilibrium theory of quantum thermodynamics for noninteracting open quantum systems strongly coupled to their reservoirs within the framework of the nonequilibrium Green's functions. The energy of the system and its coupling to the reservoirs are controlled by a slow external time-dependent force treated to first order beyond the quasistatic limit. We derive the four basic laws of thermodynamics and characterize reversible transformations. Stochastic thermodynamics is recovered in the weak coupling limit.

  13. Thermodynamically consistent model calibration in chemical kinetics

    Directory of Open Access Journals (Sweden)

    Goutsias John

    2011-05-01

    Full Text Available Abstract Background The dynamics of biochemical reaction systems are constrained by the fundamental laws of thermodynamics, which impose well-defined relationships among the reaction rate constants characterizing these systems. Constructing biochemical reaction systems from experimental observations often leads to parameter values that do not satisfy the necessary thermodynamic constraints. This can result in models that are not physically realizable and may lead to inaccurate, or even erroneous, descriptions of cellular function. Results We introduce a thermodynamically consistent model calibration (TCMC method that can be effectively used to provide thermodynamically feasible values for the parameters of an open biochemical reaction system. The proposed method formulates the model calibration problem as a constrained optimization problem that takes thermodynamic constraints (and, if desired, additional non-thermodynamic constraints into account. By calculating thermodynamically feasible values for the kinetic parameters of a well-known model of the EGF/ERK signaling cascade, we demonstrate the qualitative and quantitative significance of imposing thermodynamic constraints on these parameters and the effectiveness of our method for accomplishing this important task. MATLAB software, using the Systems Biology Toolbox 2.1, can be accessed from http://www.cis.jhu.edu/~goutsias/CSS lab/software.html. An SBML file containing the thermodynamically feasible EGF/ERK signaling cascade model can be found in the BioModels database. Conclusions TCMC is a simple and flexible method for obtaining physically plausible values for the kinetic parameters of open biochemical reaction systems. It can be effectively used to recalculate a thermodynamically consistent set of parameter values for existing thermodynamically infeasible biochemical reaction models of cellular function as well as to estimate thermodynamically feasible values for the parameters of new

  14. Thermodynamics of Enzyme-Catalyzed Reactions Database

    Science.gov (United States)

    SRD 74 Thermodynamics of Enzyme-Catalyzed Reactions Database (Web, free access)   The Thermodynamics of Enzyme-Catalyzed Reactions Database contains thermodynamic data on enzyme-catalyzed reactions that have been recently published in the Journal of Physical and Chemical Reference Data (JPCRD). For each reaction the following information is provided: the reference for the data, the reaction studied, the name of the enzyme used and its Enzyme Commission number, the method of measurement, the data and an evaluation thereof.

  15. INTEGRAL sees transient activity in the Galactic Bulge: XTE J1751-305 and GRS 1741.9-2853 in outburst

    NARCIS (Netherlands)

    Chenevez, J.; Kuulkers, E.; Beckmann, V.; Bird, A.; Brandt, S.; Domingo, A.; Ebisawa, K.; Jonker, P.; Kretschmar, P.; Markwardt, C.; Oosterbroek, T.; Paizis, A.; Risquez, D.; Sanchez-Fernandez, C.; Shaw, S.; Wijnands, R.

    2009-01-01

    INTEGRAL monitoring observations of the Galactic Bulge (e.g. ATels #438 and #1944) have been performed between 2009 Oct 7th 20:29 and 8th 00:11 (UTC) during which transient activity from a few known sources has been recorded with respect to an observation 6 days earlier. The transient low-mass X-ray

  16. INTEGRAL Galactic bulge monitoring observations of GRO J1750-27 (AX J1749.1-2639), H1743-322 and SLX 1746-331

    NARCIS (Netherlands)

    Kuulkers, E.; Beckmann, V.; Shaw, S.; Brandt, S.; Chenevez, J.; Courvoisier, T.J.L.; Domingo, A.; Ebisawa, K.; Jonker, P.; Kretschmar, P.; Markwardt, C.; Oosterbroek, T.; Paizis, A.; Risquez, D.; Sanchez-Fernandez, C.; Wijnands, R.

    2008-01-01

    A new season of the INTEGRAL Galactic Bulge monitoring program (see ATels #438, #874, #1005; Kuulkers et al. 2007, A&A 466, 595) started, with observations on UT 11 Feb 2008, 16:33-18:07. We here report on results from three currently active transient sources. The IBIS/ISGRI and JEM-X1 images show a

  17. INTEGRAL Galactic bulge monitoring observations of GRO J1750-27 (AX J1749.1-2639), H1743-322 and SLX 1746-331

    DEFF Research Database (Denmark)

    Kuulkers, E.; Beckmann, V.; Shaw, S.

    2008-01-01

    A new season of the INTEGRAL Galactic Bulge monitoring program (see ATels #438, #874, #1005; Kuulkers et al. 2007, A&A 466, 595) started, with observations on UT 11 Feb 2008, 16:33-18:07. We here report on results from three currently active transient sources. The IBIS/ISGRI and JEM-X1 images sho...

  18. Reduction of foveal bulges and other anatomical changes in fellow eyes of patients with unilateral idiopathic macular hole without vitreomacular pathologic changes.

    Science.gov (United States)

    Delas, Barbara; Julio, Gemma; Fernández-Vega, Álvaro; Casaroli-Marano, Ricardo P; Nadal, Jeroni

    2017-11-01

    To compare the foveal characteristics in fellow eyes (FE) of patients with unilateral idiopathic macular hole without vitreomacular pathologic changes with eyes of healthy controls. Forty-seven FE and 52 eyes of 52 age- and sex-matched healthy controls were studied. Quantitative assessment of the dome-shaped appearance of the hyperreflective lines that represent external limiting membrane (ELM_bulge) and inner outer segment junctions (IS/OS_bulge) were made by optical coherence tomography (OCT) images. Inner retinal complex thickness (IRCT) was quantitatively assessed at 1000 and 2000 μm of the foveal center in nasal and temporal quadrants. Presence of alterations in the inner retinal outer layers and central foveal thickness (CFT) were also analyzed. Significantly lower ELM_bulge (p < 0.0001; Mann-Whitney test) and IS/OS_bulge (p < 0.001; student t test) and higher cases with COST alterations, expressed as a diffuse line (p < 0.006; Chi2 test) were found in FE than control eyes. IRCT were significantly reduced in FE at all the studied locations when comparing to control eyes (p < 0.05; student t test), maintaining anatomical proportionality among locations. FE without pathologic vitreomacular interactions seems to present some central cone alterations that may be related to other causes than vitreomacular traction.

  19. Ab initio thermodynamic results for warm dense matter

    Science.gov (United States)

    Bonitz, Michael

    2016-10-01

    Warm dense matter (WDM) - an exotic state where electrons are quantum degenerate and ions may be strongly correlated - is ubiquitous in dense astrophysical plasmas and highly compressed laboratory systems including inertial fusion. Accurate theoretical predictions require precision thermodynamic data for the electron gas at high density and finite temperature around the Fermi temperature. First such data have been obtained by restricted path integral Monte Carlo (restricted PIMC) simulations and transformed into analytical fits for the free energy. Such results are also key input for novel finite temperature density functional theory. However, the RPIMC data of Ref. 1 are limited to moderate densities, and even there turned out to be surprisingly inaccurate, which is a consequence of the fermion sign problem. These problems were recently overcome by the development of alternative QMC approaches in Kiel (configuration PIMC and permutation blocking PIMC) and Imperial College (Density matrix QMC). The three methods have their strengths and limitations in complementary parameter regions and provide highly accurate thermodynamic data for the electronic contributions in WDM. While the original results were obtained for small particle numbers, recently accurate finite size corrections were derived allowing to compute ab initio thermodynamic data with an unprecedented accuracy of better than 0.3 percent. This provides the final step for the use as benchmark data for experiments and models of Warm dense matter. Co-authors: T. Schoof, S. Groth, T. Dornheim, F. D. Malone, M. Foulkes, and T. Sjostroem, Funded by: DFG via SFB-TR24 and project BO1366-10.

  20. Sediment budget on African passive margins: a record of margin bulges and far field very long wavelength deformations

    Science.gov (United States)

    Guillocheau, Francois; Robin, Cécile; Baby, Guillaume; Simon, Brendan; Rouby, Delphine; Loparev, Artiom

    2017-04-01

    The post-rift siliciclastic sediment budget of passive margins is a function of (1) the deformation (uplift) of the upstream catchment, of (2) the climate (precipitation) regime and of (3) the oceanic circulation (mainly since Miocene times). The main questions in source to sink studies are (1) to quantify the relative importance of the erosion due to uplifts or to precipitation changes and (2) to characterize the source of the sediments. A source to sink study was carried out in Western, Central and Austral Africa, characterized by anorogenic relief (plains and plateaus) that record long (several 100 km) to very long (several 1000 km) wavelength deformations respectively of lithospheric and mantle origin. The sink measurement was based on seismic lines and wells (industrial - IODP) using the VolumeEstimator software including the calculation of the uncertainties (Guillocheau et al., 2013, Basin Research). The source study was performed using dated stepped planation surfaces (etchplains and pediplains), mappable at catchments-scale (Guillocheau et al., in press, Gondwana Research). Results: (1) Deformation (uplift) is the dominant control of the sediment budget. Climate (precipitation) changes only enhance or inhibit a deformation-controlled flux. (2) The sources of siliciclastic sediments are either closed marginal bulges or far field domes due to mantle dynamics with river by-passing over long-lasting polygenic surfaces located between the bulges and domes. Two main periods of African-scale deformations (contemporaneous with an increase of the sedimentary flux) are confirmed, one during Late Cretaceous (Turonian-Coniacian) and the second around the Eocene-Oligocene boundary with a gap and intense chemical erosion from 75 Ma and mainly from 65 to 40 Ma.

  1. OGLE-2016-BLG-1190Lb: The First Spitzer Bulge Planet Lies Near the Planet/Brown-dwarf Boundary

    Science.gov (United States)

    Ryu, Y.-H.; Yee, J. C.; Udalski, A.; Bond, I. A.; Shvartzvald, Y.; Zang, W.; Figuera Jaimes, R.; Jørgensen, U. G.; Zhu, W.; Huang, C. X.; Jung, Y. K.; Albrow, M. D.; Chung, S.-J.; Gould, A.; Han, C.; Hwang, K.-H.; Shin, I.-G.; Cha, S.-M.; Kim, D.-J.; Kim, H.-W.; Kim, S.-L.; Lee, C.-U.; Lee, D.-J.; Lee, Y.; Park, B.-G.; Pogge, R. W.; KMTNet Collaboration; Calchi Novati, S.; Carey, S.; Henderson, C. B.; Beichman, C.; Gaudi, B. S.; Spitzer team; Mróz, P.; Poleski, R.; Skowron, J.; Szymański, M. K.; Soszyński, I.; Kozłowski, S.; Pietrukowicz, P.; Ulaczyk, K.; Pawlak, M.; OGLE Collaboration; Abe, F.; Asakura, Y.; Barry, R.; Bennett, D. P.; Bhattacharya, A.; Donachie, M.; Evans, P.; Fukui, A.; Hirao, Y.; Itow, Y.; Kawasaki, K.; Koshimoto, N.; Li, M. C. A.; Ling, C. H.; Masuda, K.; Matsubara, Y.; Miyazaki, S.; Muraki, Y.; Nagakane, M.; Ohnishi, K.; Ranc, C.; Rattenbury, N. J.; Saito, To.; Sharan, A.; Sullivan, D. J.; Sumi, T.; Suzuki, D.; Tristram, P. J.; Yamada, T.; Yamada, T.; Yonehara, A.; MOA Collaboration; Bryden, G.; Howell, S. B.; Jacklin, S.; UKIRT Microlensing Team; Penny, M. T.; Mao, S.; Fouqué, Pascal; Wang, T.; CFHT-K2C9 Microlensing Survey group; Street, R. A.; Tsapras, Y.; Hundertmark, M.; Bachelet, E.; Dominik, M.; Li, Z.; Cross, S.; Cassan, A.; Horne, K.; Schmidt, R.; Wambsganss, J.; Ment, S. K.; Maoz, D.; Snodgrass, C.; Steele, I. A.; RoboNet Team; Bozza, V.; Burgdorf, M. J.; Ciceri, S.; D’Ago, G.; Evans, D. F.; Hinse, T. C.; Kerins, E.; Kokotanekova, R.; Longa, P.; MacKenzie, J.; Popovas, A.; Rabus, M.; Rahvar, S.; Sajadian, S.; Skottfelt, J.; Southworth, J.; von Essen, C.; MiNDSTEp Team

    2018-01-01

    We report the discovery of OGLE-2016-BLG-1190Lb, which is likely to be the first Spitzer microlensing planet in the Galactic bulge/bar, an assignation that can be confirmed by two epochs of high-resolution imaging of the combined source–lens baseline object. The planet’s mass, M p = 13.4 ± 0.9 M J , places it right at the deuterium-burning limit, i.e., the conventional boundary between “planets” and “brown dwarfs.” Its existence raises the question of whether such objects are really “planets” (formed within the disks of their hosts) or “failed stars” (low-mass objects formed by gas fragmentation). This question may ultimately be addressed by comparing disk and bulge/bar planets, which is a goal of the Spitzer microlens program. The host is a G dwarf, M host = 0.89 ± 0.07 M ⊙, and the planet has a semimajor axis a ∼ 2.0 au. We use Kepler K2 Campaign 9 microlensing data to break the lens-mass degeneracy that generically impacts parallax solutions from Earth–Spitzer observations alone, which is the first successful application of this approach. The microlensing data, derived primarily from near-continuous, ultradense survey observations from OGLE, MOA, and three KMTNet telescopes, contain more orbital information than for any previous microlensing planet, but not quite enough to accurately specify the full orbit. However, these data do permit the first rigorous test of microlensing orbital-motion measurements, which are typically derived from data taken over <1% of an orbital period.

  2. Treatise on irreversible and statistical thermodynamics an introduction to nonclassical thermodynamics

    CERN Document Server

    Yourgrau, Wolfgang; Raw, Gough

    2002-01-01

    Extensively revised edition of a much-respected work examines thermodynamics of irreversible processes, general principles of statistical thermodynamics, assemblies of noninteracting structureless particles, and statistical theory. 1966 edition.

  3. Black hole thermodynamics with conical defects

    Science.gov (United States)

    Appels, Michael; Gregory, Ruth; Kubizňák, David

    2017-05-01

    Recently we have shown [1] how to formulate a thermodynamic first law for a single (charged) accelerated black hole in AdS space by fixing the conical deficit angles present in the spacetime. Here we show how to generalise this result, formulating thermodynamics for black holes with varying conical deficits. We derive a new potential for the varying tension defects: the thermodynamic length, both for accelerating and static black holes. We discuss possible physical processes in which the tension of a string ending on a black hole might vary, and also map out the thermodynamic phase space of accelerating black holes and explore their critical phenomena.

  4. Coherence and measurement in quantum thermodynamics

    Science.gov (United States)

    Kammerlander, P.; Anders, J.

    2016-01-01

    Thermodynamics is a highly successful macroscopic theory widely used across the natural sciences and for the construction of everyday devices, from car engines to solar cells. With thermodynamics predating quantum theory, research now aims to uncover the thermodynamic laws that govern finite size systems which may in addition host quantum effects. Recent theoretical breakthroughs include the characterisation of the efficiency of quantum thermal engines, the extension of classical non-equilibrium fluctuation theorems to the quantum regime and a new thermodynamic resource theory has led to the discovery of a set of second laws for finite size systems. These results have substantially advanced our understanding of nanoscale thermodynamics, however putting a finger on what is genuinely quantum in quantum thermodynamics has remained a challenge. Here we identify information processing tasks, the so-called projections, that can only be formulated within the framework of quantum mechanics. We show that the physical realisation of such projections can come with a non-trivial thermodynamic work only for quantum states with coherences. This contrasts with information erasure, first investigated by Landauer, for which a thermodynamic work cost applies for classical and quantum erasure alike. Repercussions on quantum work fluctuation relations and thermodynamic single-shot approaches are also discussed. PMID:26916503

  5. Thermodynamic optimization of a Penrose process: an engineers' approach to black hole thermodynamics

    OpenAIRE

    Bravetti, Alessandro; Gruber, Christine; Lopez-Monsalvo, Cesar S.

    2015-01-01

    In this work we present a new view on the thermodynamics of black holes introducing effects of irreversibility by employing thermodynamic optimization and finite-time thermodynamics. These questions are of importance both in physics and in engineering, combining standard thermodynamics with optimal control theory in order to find optimal protocols and bounds for realistic processes without assuming anything about the microphysics involved. We find general bounds on the maximum work and the ef...

  6. Thermodynamic features of dioxins’ adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Prisciandaro, Marina [Department of Industrial and Information Engineering and of Economics, University of L’Aquila, Viale Giovanni Gronchi 18, L’Aquila 67100 (Italy); Piemonte, Vincenzo, E-mail: v.piemonte@unicampus.it [Faculty of Engineering, University Campus Biomedico of Rome, Via Alvaro del Portillo 21, Rome 00128 (Italy); Mazziotti di Celso, Giuseppe [Faculty of Bioscience, University of Teramo, Via R. Balzarini, 1, 64100 Teramo (Italy); Ronconi, Silvia [Arta Abruzzo, Department of L’Aquila, Bazzano (AQ), 67100 L’Aquila (Italy); Capocelli, Mauro [Faculty of Engineering, University Campus Biomedico of Rome, Via Alvaro del Portillo 21, Rome 00128 (Italy)

    2017-02-15

    Highlights: • We develop the P-T diagram for six PCDD. • We derive theoretical adsorption isotherms according to the Langmuir’s model. • We calculate K and w{sub max} values for several temperatures. • We estimate the adsorption heat with a good agreement with literature data. - Abstract: In this paper, the six more poisonous species among all congeners of dioxin group are taken into account, and the P-T diagram for each of them is developed. Starting from the knowledge of vapour tensions and thermodynamic parameters, the theoretical adsorption isotherms are calculated according to the Langmuir’s model. In particular, the Langmuir isotherm parameters (K and w{sub max}) have been validated through the estimation of the adsorption heat (ΔH{sub ads}), which varies in the range 20–24 kJ/mol, in agreement with literature values. This result will allow to put the thermodynamical basis for a rational design of different process units devoted to dioxins removal.

  7. Bioengineering thermodynamics of biological cells.

    Science.gov (United States)

    Lucia, Umberto

    2015-12-01

    Cells are open complex thermodynamic systems. They can be also regarded as complex engines that execute a series of chemical reactions. Energy transformations, thermo-electro-chemical processes and transports phenomena can occur across the cells membranes. Moreover, cells can also actively modify their behaviours in relation to changes in their environment. Different thermo-electro-biochemical behaviours occur between health and disease states. But, all the living systems waste heat, which is no more than the result of their internal irreversibility. This heat is dissipated into the environment. But, this wasted heat represent also a sort of information, which outflows from the cell toward its environment, completely accessible to any observer. The analysis of irreversibility related to this wasted heat can represent a new approach to study the behaviour of the cells themselves and to control their behaviours. So, this approach allows us to consider the living systems as black boxes and analyze only the inflows and outflows and their changes in relation to the modification of the environment. Therefore, information on the systems can be obtained by analyzing the changes in the cell heat wasted in relation to external perturbations. The bioengineering thermodynamics bases are summarized and used to analyse possible controls of the calls behaviours based on the control of the ions fluxes across the cells membranes.

  8. Thermodynamic indicators for environmental certification.

    Science.gov (United States)

    Panzieri, Margherita; Porcelli, Marcello; Pulselli, Federico Maria

    2002-09-01

    The Earth is an open thermodynamic system, that remains in a steady state far from the equilibrium, through energy and matter exchanges with the surrounding environment. These natural constraints, which prevent the system from maximizing its entropy, are threatened by human action and our ecosystem needs urgent protection. In this viewpoint the environmental certification was born, according to international standards ISO 14001, ISO 14040, and European Regulation EMAS. These are voluntary adhesions to a program of environmental protection by companies, administrations and organizations which, starting from the respect of the existing environmental laws and regulations, decide to further improve their environmental performance. To obtain and maintain certification of a system is necessary to apply some indicators to evaluate its environmental performance and to demonstrate its progressive improvement. Here we propose to use for this purpose the thermodynamic indicators produced from energy analysis by Odum. The case study is Montalcino city (Italy) and energy indicators are used to evaluate environmental performance of this system where exist different activities, from agricultural productions, to tourism. Results show that energy analysis could become a valid standard monitoring method for environmental certification, especially in consideration of its wide application field.

  9. Balanced Biochemical Reactions: A New Approach to Unify Chemical and Biochemical Thermodynamics

    Science.gov (United States)

    Sabatini, Antonio; Vacca, Alberto; Iotti, Stefano

    2012-01-01

    A novel procedure is presented which, by balancing elements and electric charge of biochemical reactions which occur at constant pH and pMg, allows assessing the thermodynamics properties of reaction ΔrG′0, ΔrH′0, ΔrS′0 and the change in binding of hydrogen and magnesium ions of these reactions. This procedure of general applicability avoids the complex calculations required by the use of the Legendre transformed thermodynamic properties of formation ΔfG′0, ΔfH′0 and ΔfS′0 hitherto considered an obligatory prerequisite to deal with the thermodynamics of biochemical reactions. As a consequence, the term “conditional” is proposed in substitution of “Legendre transformed” to indicate these thermodynamics properties. It is also shown that the thermodynamic potential G is fully adequate to give a criterion of spontaneous chemical change for all biochemical reactions and then that the use of the Legendre transformed G′ is unnecessary. The procedure proposed can be applied to any biochemical reaction, making possible to re-unify the two worlds of chemical and biochemical thermodynamics, which so far have been treated separately. PMID:22247780

  10. Misuse of thermodynamics in the interpretation of isothermal titration calorimetry data for ligand binding to proteins.

    Science.gov (United States)

    Pethica, Brian A

    2015-03-01

    Isothermal titration calorimetry (ITC) has given a mass of data on the binding of small molecules to proteins and other biopolymers, with particular interest in drug binding to proteins chosen as therapeutic indicators. Interpretation of the enthalpy data usually follows an unsound protocol that uses thermodynamic relations in circumstances where they do not apply. Errors of interpretation include incomplete definitions of ligand binding and equilibrium constants and neglect of the non-ideality of the solutions under study, leading to unreliable estimates of standard free energies and entropies of binding. The mass of reported thermodynamic functions for ligand binding to proteins estimated from ITC enthalpies alone is consequently of uncertain thermodynamic significance and utility. ITC and related experiments to test the protocol assumptions are indicated. A thermodynamic procedure avoiding equilibrium constants or other reaction models and not requiring protein activities is given. The discussion draws attention to the fundamental but neglected relation between the thermodynamic activity and bioactivity of drugs and to the generally unknown thermodynamic status of ligand solutions, which for drugs relates directly to effective therapeutic dosimetry. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Balanced biochemical reactions: a new approach to unify chemical and biochemical thermodynamics.

    Science.gov (United States)

    Sabatini, Antonio; Vacca, Alberto; Iotti, Stefano

    2012-01-01

    A novel procedure is presented which, by balancing elements and electric charge of biochemical reactions which occur at constant pH and pMg, allows assessing the thermodynamics properties of reaction Δ(r)G'⁰, Δ(r)H'⁰, Δ(r)S'⁰ and the change in binding of hydrogen and magnesium ions of these reactions. This procedure of general applicability avoids the complex calculations required by the use of the Legendre transformed thermodynamic properties of formation Δ(f)G'⁰, Δ(f)H'⁰ and Δ(f)S'⁰ hitherto considered an obligatory prerequisite to deal with the thermodynamics of biochemical reactions. As a consequence, the term "conditional" is proposed in substitution of "Legendre transformed" to indicate these thermodynamics properties. It is also shown that the thermodynamic potential G is fully adequate to give a criterion of spontaneous chemical change for all biochemical reactions and then that the use of the Legendre transformed G' is unnecessary. The procedure proposed can be applied to any biochemical reaction, making possible to re-unify the two worlds of chemical and biochemical thermodynamics, which so far have been treated separately.

  12. Balanced biochemical reactions: a new approach to unify chemical and biochemical thermodynamics.

    Directory of Open Access Journals (Sweden)

    Antonio Sabatini

    Full Text Available A novel procedure is presented which, by balancing elements and electric charge of biochemical reactions which occur at constant pH and pMg, allows assessing the thermodynamics properties of reaction Δ(rG'⁰, Δ(rH'⁰, Δ(rS'⁰ and the change in binding of hydrogen and magnesium ions of these reactions. This procedure of general applicability avoids the complex calculations required by the use of the Legendre transformed thermodynamic properties of formation Δ(fG'⁰, Δ(fH'⁰ and Δ(fS'⁰ hitherto considered an obligatory prerequisite to deal with the thermodynamics of biochemical reactions. As a consequence, the term "conditional" is proposed in substitution of "Legendre transformed" to indicate these thermodynamics properties. It is also shown that the thermodynamic potential G is fully adequate to give a criterion of spontaneous chemical change for all biochemical reactions and then that the use of the Legendre transformed G' is unnecessary. The procedure proposed can be applied to any biochemical reaction, making possible to re-unify the two worlds of chemical and biochemical thermodynamics, which so far have been treated separately.

  13. Thermodynamics of antibody-antigen interaction revealed by mutation analysis of antibody variable regions.

    Science.gov (United States)

    Akiba, Hiroki; Tsumoto, Kouhei

    2015-07-01

    Antibodies (immunoglobulins) bind specific molecules (i.e. antigens) with high affinity and specificity. In order to understand their mechanisms of recognition, interaction analysis based on thermodynamic and kinetic parameters, as well as structure determination is crucial. In this review, we focus on mutational analysis which gives information about the role of each amino acid residue in antibody-antigen interaction. Taking anti-hen egg lysozyme antibodies and several anti-small molecule antibodies, the energetic contribution of hot-spot and non-hot-spot residues is discussed in terms of thermodynamics. Here, thermodynamics of the contribution from aromatic, charged and hydrogen bond-forming amino acids are discussed, and their different characteristics have been elucidated. The information gives fundamental understanding of the antibody-antigen interaction. Furthermore, the consequences of antibody engineering are analysed from thermodynamic viewpoints: humanization to reduce immunogenicity and rational design to improve affinity. Amino acid residues outside hot-spots in the interface play important roles in these cases, and thus thermodynamic and kinetic parameters give much information about the antigen recognition. Thermodynamic analysis of mutant antibodies thus should lead to advanced strategies to design and select antibodies with high affinity. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  14. Stochastic thermodynamics of quantum maps with and without equilibrium.

    Science.gov (United States)

    Barra, Felipe; Lledó, Cristóbal

    2017-11-01

    We study stochastic thermodynamics for a quantum system of interest whose dynamics is described by a completely positive trace-preserving (CPTP) map as a result of its interaction with a thermal bath. We define CPTP maps with equilibrium as CPTP maps with an invariant state such that the entropy production due to the action of the map on the invariant state vanishes. Thermal maps are a subgroup of CPTP maps with equilibrium. In general, for CPTP maps, the thermodynamic quantities, such as the entropy production or work performed on the system, depend on the combined state of the system plus its environment. We show that these quantities can be written in terms of system properties for maps with equilibrium. The relations that we obtain are valid for arbitrary coupling strengths between the system and the thermal bath. The fluctuations of thermodynamic quantities are considered in the framework of a two-point measurement scheme. We derive the entropy production fluctuation theorem for general maps and a fluctuation relation for the stochastic work on a system that starts in the Gibbs state. Some simplifications for the probability distributions in the case of maps with equilibrium are presented. We illustrate our results by considering spin 1/2 systems under thermal maps, nonthermal maps with equilibrium, maps with nonequilibrium steady states, and concatenations of them. Finally, and as an important application, we consider a particular limit in which the concatenation of maps generates a continuous time evolution in Lindblad form for the system of interest, and we show that the concept of maps with and without equilibrium translates into Lindblad equations with and without quantum detailed balance, respectively. The consequences for the thermodynamic quantities in this limit are discussed.

  15. Stochastic thermodynamics of quantum maps with and without equilibrium

    Science.gov (United States)

    Barra, Felipe; Lledó, Cristóbal

    2017-11-01

    We study stochastic thermodynamics for a quantum system of interest whose dynamics is described by a completely positive trace-preserving (CPTP) map as a result of its interaction with a thermal bath. We define CPTP maps with equilibrium as CPTP maps with an invariant state such that the entropy production due to the action of the map on the invariant state vanishes. Thermal maps are a subgroup of CPTP maps with equilibrium. In general, for CPTP maps, the thermodynamic quantities, such as the entropy production or work performed on the system, depend on the combined state of the system plus its environment. We show that these quantities can be written in terms of system properties for maps with equilibrium. The relations that we obtain are valid for arbitrary coupling strengths between the system and the thermal bath. The fluctuations of thermodynamic quantities are considered in the framework of a two-point measurement scheme. We derive the entropy production fluctuation theorem for general maps and a fluctuation relation for the stochastic work on a system that starts in the Gibbs state. Some simplifications for the probability distributions in the case of maps with equilibrium are presented. We illustrate our results by considering spin 1/2 systems under thermal maps, nonthermal maps with equilibrium, maps with nonequilibrium steady states, and concatenations of them. Finally, and as an important application, we consider a particular limit in which the concatenation of maps generates a continuous time evolution in Lindblad form for the system of interest, and we show that the concept of maps with and without equilibrium translates into Lindblad equations with and without quantum detailed balance, respectively. The consequences for the thermodynamic quantities in this limit are discussed.

  16. Universal thermodynamics in different gravity theories: Conditions for generalized second law of thermodynamics and thermodynamical equilibrium on the horizons

    CERN Document Server

    Mitra, Saugata; Chakraborty, Subenoy

    2016-01-01

    The present work deals with a detailed study of universal thermodynamics in different modified gravity theories. The validity of the generalized second law of thermodynamics (GSLT) and thermodynamical equilibrium (TE) of the Universe bounded by a horizon (apparent/event) in f(R)-gravity, Einstein-Gauss-Bonnet gravity, RS-II brane scenario and DGP brane model has been investigated. In the perspective of recent observational evidences, the matter in the Universe is chosen as interacting holographic dark energy model. The entropy on the horizons are evaluated from the validity of the unified first law and as a result there is a correction (in integral form) to the usual Bekenstein entropy. The other thermodynamical parameter namely temperature on the horizon is chosen as the recently introduced corrected Hawking temperature. The above thermodynamical analysis is done for homogeneous and isotropic flat FLRW model of the Universe. The restrictions for the validity of GSLT and the TE are presented in tabular form f...

  17. Thermodynamic equilibrium at heterogeneous pressure

    Science.gov (United States)

    Vrijmoed, Johannes C.; Podladchikov, Yuri Y.

    2014-05-01

    Recent advances in metamorphic petrology point out the importance of grain-scale pressure variations in high-temperature metamorphic rocks. Pressures derived from chemical zonation using unconventional geobarometry based on equal chemical potentials fit mechanically feasible pressure variations. Here a thermodynamic equilibrium method is presented that predicts chemical zoning as a result of pressure variations by Gibbs energy minimization. Equilibrium thermodynamic prediction of the chemical zoning in the case of pressure heterogeneity is done by constraint Gibbs minimization using linear programming techniques. Compositions of phases considered in the calculation are discretized into 'pseudo-compounds' spanning the entire compositional space. Gibbs energies of these discrete compounds are generated for a given range and resolution of pressures for example derived by barometry or from mechanical model predictions. Gibbs energy minimization is subsequently performed considering all compounds of different composition and pressure. In addition to constraining the system composition a certain proportion of the system is constraint at a specified pressure. Input pressure variations need to be discretized and each discrete pressure defines an additional constraint for the minimization. The proportion of the system at each different pressure is equally distributed over the number of input pressures. For example if two input pressures P1 and P2 are specified, two constraints are added: 50 percent of the system is constraint at P1 while the remaining 50 percent is constraint at P2. The method has been tested for a set of 10 input pressures obtained by Tajčmanová et al. (2014) using their unconventional geobarometry method in a plagioclase rim around kyanite. Each input pressure is added as constraint to the minimization (1/10 percent of the system for each discrete pressure). Constraining the system composition to the average composition of the plagioclase rim

  18. Quantum quenches in the thermodynamic limit.

    Science.gov (United States)

    Rigol, M

    2014-05-02

    We introduce a linked-cluster based computational approach that allows one to study quantum quenches in lattice systems in the thermodynamic limit. This approach is used to study quenches in one-dimensional lattices. We provide evidence that, in the thermodynamic limit, thermalization occurs in the nonintegrable regime but fails at integrability. A phase transitionlike behavior separates the two regimes.

  19. Impact of Thermodynamic Principles in Systems Biology

    NARCIS (Netherlands)

    Heijnen, J.J.

    2010-01-01

    It is shown that properties of biological systems which are relevant for systems biology motivated mathematical modelling are strongly shaped by general thermodynamic principles such as osmotic limit, Gibbs energy dissipation, near equilibria and thermodynamic driving force. Each of these aspects

  20. Simple, Chemoselective Hydrogenation with Thermodynamic Stereocontrol

    OpenAIRE

    Iwasaki, Kotaro; Wan, Kanny K.; Oppedisano, Alberto; Crossley, Steven W. M.; Shenvi, Ryan A.

    2014-01-01

    Few methods permit the hydrogenation of alkenes to a thermodynamically favored configuration when steric effects dictate the alternative trajectory of hydrogen delivery. Dissolving metal reduction achieves this control, but with extremely low functional group tolerance. Here we demonstrate a catalytic hydrogenation of alkenes that affords the thermodynamic alkane products with remarkably broad functional group compatibility and rapid reaction rates at standard temperature and pressure.

  1. Simple, chemoselective hydrogenation with thermodynamic stereocontrol.

    Science.gov (United States)

    Iwasaki, Kotaro; Wan, Kanny K; Oppedisano, Alberto; Crossley, Steven W M; Shenvi, Ryan A

    2014-01-29

    Few methods permit the hydrogenation of alkenes to a thermodynamically favored configuration when steric effects dictate the alternative trajectory of hydrogen delivery. Dissolving metal reduction achieves this control, but with extremely low functional group tolerance. Here we demonstrate a catalytic hydrogenation of alkenes that affords the thermodynamic alkane products with remarkably broad functional group compatibility and rapid reaction rates at standard temperature and pressure.

  2. Warming to ecocide a thermodynamic diagnosis

    CERN Document Server

    Sangster, Alan J

    2011-01-01

    Suggests a route to avoiding runaway climate change by reinstating the greenhouse thermostat to its full operational capacity Addresses mankind's contribution to climate change from a thermodynamic perspective Describes and illustrates the power of thermodynamics to furnish insights into the thermal behaviour of complex physical systems

  3. Thermodynamic Ground States of Complex Oxide Heterointerfaces

    DEFF Research Database (Denmark)

    Gunkel, F.; Hoffmann-Eifert, S.; Heinen, R. A.

    2017-01-01

    The formation mechanism of 2-dimensional electron gases (2DEGs) at heterointerfaces between nominally insulating oxides is addressed with a thermodynamical approach. We provide a comprehensive analysis of the thermodynamic ground states of various 2DEG systems directly probed in high temperature...

  4. An Experimental Determination of Thermodynamic Values

    Science.gov (United States)

    Antony, Erling; Muccianti, Christine; Vogel, Tracy

    2012-01-01

    Measurements have been added to an old demonstration of chemical equilibria allowing the determination of thermodynamic constants. The experiment allows the students an opportunity to merge qualitative observations associated with Le Chatelier's principle and thermodynamic calculations using graphical techniques. (Contains 4 figures.)

  5. Detonation Jet Engine. Part 1--Thermodynamic Cycle

    Science.gov (United States)

    Bulat, Pavel V.; Volkov, Konstantin N.

    2016-01-01

    We present the most relevant works on jet engine design that utilize thermodynamic cycle of detonative combustion. The efficiency advantages of thermodynamic detonative combustion cycle over Humphrey combustion cycle at constant volume and Brayton combustion cycle at constant pressure were demonstrated. An ideal Ficket-Jacobs detonation cycle, and…

  6. Thermodynamic Property Needs for the Oleochemical Industry

    DEFF Research Database (Denmark)

    Ana Perederic, Olivia; Kalakul, Sawitree; Sarup, Bent

    and/or reliable thermodynamic models for the chemicals involved. Limited availability ofconsistent physical and thermodynamic properties of lipids compounds and their mixtures lead to difficulties with the use of process simulators for process synthesis and design, since all themodels to be used...

  7. Thermodynamics of charged and rotating black strings

    Science.gov (United States)

    Fatima, Aeeman; Saifullah, K.

    2012-10-01

    We study thermodynamics of cylindrically symmetric black holes. Uncharged as well as charged and rotating objects have been discussed. We derive surface gravity and hence the Hawking temperature and entropy for all these cases. We correct some results in the literature and present new ones. It is seen that thermodynamically these black configurations behave differently from spherically symmetric objects.

  8. Thermodynamics and heat transfer in fire fighting

    Science.gov (United States)

    Romanenko, P. N.; Koshmarov, Y. A.; Bashkirtsev, M. P.

    1985-05-01

    The book presents the fundamental principles of thermodynamics and heat transfer with particular reference to their application in problems related to fire prevention. Special attention is given to the study of unsteady heat transfer, radiant heat transfer (including radiation from flames to the surrounding), thermodynamic analysis of the growth of fires and theoretical modeling of fires in building.

  9. The thermodynamic solar energy; Le solaire thermodynamique

    Energy Technology Data Exchange (ETDEWEB)

    Rivoire, B. [Centre National de la Recherche Scientifique (CNRS-IMP), 66 - Perpignan (France)

    2002-04-01

    The thermodynamic solar energy is the technic in the whole aiming to transform the solar radiation energy in high temperature heat and then in mechanical energy by a thermodynamic cycle. These technic are most often at an experimental scale. This paper describes and analyzes the research programs developed in the advanced countries, since 1980. (A.L.B.)

  10. Understanding the Thermodynamics of Biological Order

    Science.gov (United States)

    Peterson, Jacob

    2012-01-01

    By growth in size and complexity (i.e., changing from more probable to less probable states), plants and animals appear to defy the second law of thermodynamics. The usual explanation describes the input of nutrient and sunlight energy into open thermodynamic systems. However, energy input alone does not address the ability to organize and create…

  11. Friction Force: From Mechanics to Thermodynamics

    Science.gov (United States)

    Ferrari, Christian; Gruber, Christian

    2010-01-01

    We study some mechanical problems in which a friction force is acting on a system. Using the fundamental concepts of state, time evolution and energy conservation, we explain how to extend Newtonian mechanics to thermodynamics. We arrive at the two laws of thermodynamics and then apply them to investigate the time evolution and heat transfer of…

  12. Teaching Differentials in Thermodynamics Using Spatial Visualization

    Science.gov (United States)

    Wang, Chih-Yueh; Hou, Ching-Han

    2012-01-01

    The greatest difficulty that is encountered by students in thermodynamics classes is to find relationships between variables and to solve a total differential equation that relates one thermodynamic state variable to two mutually independent state variables. Rules of differentiation, including the total differential and the cyclic rule, are…

  13. Is multiset consequence trivial?

    Czech Academy of Sciences Publication Activity Database

    Cintula, Petr; Paoli, F.

    First Online: 08 September 2016 (2018) ISSN 0039-7857 R&D Projects: GA ČR GA13-14654S EU Projects: European Commission(XE) 689176 - SYSMICS Institutional support: RVO:67985807 Keywords : contraction-free logics * multiset consequence * substructural logics * multiple conclusions Subject RIV: BA - General Mathematics Impact factor: 0.855, year: 2016

  14. Cardiovascular consequences of hypophosphatemia.

    Science.gov (United States)

    Ariyoshi, Nobuhiro; Nogi, Masayuki; Ando, Akika; Watanabe, Hideaki; Umekawa, Sari

    2017-09-01

    Few studies have been conducted to evaluate the effect of hypophosphatemia on cardiovascular consequences. The goal of this review was to determine whether hypophosphatemia is associated with cardiovascular consequences and to increase its awareness as a new clinical entity and a reversible cause of cardiovascular consequences. We searched MEDLINE and PubMed through September 2016 for primary studies that reported the relationship between hypophosphatemia and cardiovascular consequences including cardiomyopathy and arrhythmia. A total of 937 articles were initially obtained. Of these articles, 921 publications were excluded according to the inclusion and exclusion criteria. Sixteen articles were included in this review. These articles included 3 prospective cohort studies, 1 retrospective cohort study, 7 case series or case reports, 2 case-control studies, 1 pre- vs. post-test in a single group, and 2 animal studies. The mechanisms of hypophosphatemia in cardiomyopathy and arrhythmia have been reported to be a depletion of adenosine triphosphate in myocardial cells and decreased 2,3-diphosphoglycerate in erythrocytes. Left ventricular performance seems to improve when severe hypophosphatemia is corrected, but not in those with mild to moderate hypophosphatemia. However, analyses of the relationship between cardiac function and hypophosphatemia using clinical end points have not been conducted. The association between hypophosphatemia and arrhythmia remains unclear, but anecdotal reports exist in the literature.

  15. Logical consequence for nominalists

    NARCIS (Netherlands)

    Rossberg, Marcus; Cohnitz, Daniel|info:eu-repo/dai/nl/297859099

    2009-01-01

    It has repeatedly been argued that nominalistic programmes in the philosophy of mathematics fail, since they will at some point or other involve the notion of logical consequence which is unavailable to the nominalist. In this paper we will argue that this is not the case. Using an idea of Nelson

  16. Using Negative Consequences Effectively.

    Science.gov (United States)

    Bacon, Ellen H.

    1990-01-01

    Methods of dealing with students' inappropriate behavior, noncompliance, and conflict can be implemented at different levels within the school. Schoolwide interventions include expulsion, suspension, and physical punishment. Classroom interventions include time out, verbal reprimands and commands, logical consequences, and surface management…

  17. Hepatic steatosis : metabolic consequences

    NARCIS (Netherlands)

    Boer, Adriana Maria den

    2006-01-01

    In this thesis we focused on the causes and consequences of hepatic steatosis. Epidemiological studies in humans, as well as experimental studies in animal models, have shown an association between visceral obesity and dyslipidemia, insulin resistance and type 2 diabetes mellitus. The mechanism

  18. Thermodynamic analysis of human heat and mass transfer and their impact on thermal comfort

    OpenAIRE

    Prek, Matjaž

    2015-01-01

    In this paper a thermodynamic analysis of human heat and mass transfer based on the 2nd law of thermodynamics in presented. For modelling purposes the two-node human thermal model was used. This model was improved in order to establish the exergy consumption within the human body as a consequence of heat and mass transfer and/or conversion. It is shown that the human body's exergy consumption in relation to selected human parameters exhibit a minimal value at certain combinations of environme...

  19. An introduction to thermodynamics and statistical mechanics

    CERN Document Server

    Saxena, A K

    2016-01-01

    An Introduction to Thermodynamics and Statistical Mechanics aims to serve as a text book for undergraduate hons.and postgraduate students of physics. The book covers First Law of Thermodynamics, Entropy and Second Law ofThermodynamics, Thermodynamic Relations, The Statistical Basis of Thermodynamics, Microcanonical Ensemble,Classical Statistical and Canonical Distribution, Grand Canonical Ensemble, Quantum Statistical Mechanics, PhaseTransitions, Fluctuations, Irreversible Processes and Transport Phenomena (Diffusion).SALIENT FEATURES:iC* Offers students a conceptual development of the subjectiC* Review questions at the end of chapters.NEW TO THE SECOND EDITIONiC* PVT SurfacesiC* Real Heat EnginesiC* Van der Waals Models (Qualitative Considerations)iC* Cluster ExpansioniC* Brownian Motion (Einstein's Theory)

  20. Nonequilibrium thermodynamics of restricted Boltzmann machines

    Science.gov (United States)

    Salazar, Domingos S. P.

    2017-08-01

    In this work, we analyze the nonequilibrium thermodynamics of a class of neural networks known as restricted Boltzmann machines (RBMs) in the context of unsupervised learning. We show how the network is described as a discrete Markov process and how the detailed balance condition and the Maxwell-Boltzmann equilibrium distribution are sufficient conditions for a complete thermodynamics description, including nonequilibrium fluctuation theorems. Numerical simulations in a fully trained RBM are performed and the heat exchange fluctuation theorem is verified with excellent agreement to the theory. We observe how the contrastive divergence functional, mostly used in unsupervised learning of RBMs, is closely related to nonequilibrium thermodynamic quantities. We also use the framework to interpret the estimation of the partition function of RBMs with the annealed importance sampling method from a thermodynamics standpoint. Finally, we argue that unsupervised learning of RBMs is equivalent to a work protocol in a system driven by the laws of thermodynamics in the absence of labeled data.

  1. eQuilibrator—the biochemical thermodynamics calculator

    Science.gov (United States)

    Flamholz, Avi; Noor, Elad; Bar-Even, Arren; Milo, Ron

    2012-01-01

    The laws of thermodynamics constrain the action of biochemical systems. However, thermodynamic data on biochemical compounds can be difficult to find and is cumbersome to perform calculations with manually. Even simple thermodynamic questions like ‘how much Gibbs energy is released by ATP hydrolysis at pH 5?’ are complicated excessively by the search for accurate data. To address this problem, eQuilibrator couples a comprehensive and accurate database of thermodynamic properties of biochemical compounds and reactions with a simple and powerful online search and calculation interface. The web interface to eQuilibrator (http://equilibrator.weizmann.ac.il) enables easy calculation of Gibbs energies of compounds and reactions given arbitrary pH, ionic strength and metabolite concentrations. The eQuilibrator code is open-source and all thermodynamic source data are freely downloadable in standard formats. Here we describe the database characteristics and implementation and demonstrate its use. PMID:22064852

  2. Horizon thermodynamics in fourth-order gravity

    Directory of Open Access Journals (Sweden)

    Meng-Sen Ma

    2017-03-01

    Full Text Available In the framework of horizon thermodynamics, the field equations of Einstein gravity and some other second-order gravities can be rewritten as the thermodynamic identity: dE=TdS−PdV. However, in order to construct the horizon thermodynamics in higher-order gravity, we have to simplify the field equations firstly. In this paper, we study the fourth-order gravity and convert it to second-order gravity via a so-called “Legendre transformation” at the cost of introducing two other fields besides the metric field. With this simplified theory, we implement the conventional procedure in the construction of the horizon thermodynamics in 3 and 4 dimensional spacetime. We find that the field equations in the fourth-order gravity can also be written as the thermodynamic identity. Moreover, we can use this approach to derive the same black hole mass as that by other methods.

  3. Advanced working fluids: Thermodynamic properties

    Science.gov (United States)

    Lee, Lloyd L.; Gering, Kevin L.

    1990-10-01

    Electrolytes are used as working fluids in gas fired heat pump chiller engine cycles. To find out which molecular parameters of the electrolytes impact on cycle performance, a molecular theory is developed for calculating solution properties, enthalpies, vapor-liquid equilibria, and engine cycle performance. Aqueous and ammoniac single and mixed salt solutions in single and multisolvent systems are investigated. An accurate correlation is developed to evaluate properties for concentrated electrolyte solutions. Sensitivity analysis is used to determine the impact of molecular parameters on the thermodynamic properties and cycle performance. The preferred electrolytes are of 1-1 valence type, small ion size, high molecular weight, and in strongly colligative cosolvent. The operating windows are determined for a number of absorption fluids of industrial importance.

  4. Thermodynamic cost of external control

    Science.gov (United States)

    Barato, Andre C.; Seifert, Udo

    2017-07-01

    Artificial molecular machines are often driven by the periodic variation of an external parameter. This external control exerts work on the system of which a part can be extracted as output if the system runs against an applied load. Usually, the thermodynamic cost of the process that generates the external control is ignored. Here, we derive a refined second law for such small machines that include this cost, which is, for example, generated by free energy consumption of a chemical reaction that modifies the energy landscape for such a machine. In the limit of irreversible control, this refined second law becomes the standard one. Beyond this ideal limiting case, our analysis shows that due to a new entropic term unexpected regimes can occur: the control work can be smaller than the extracted work and the work required to generate the control can be smaller than this control work. Our general inequalities are illustrated by a paradigmatic three-state system.

  5. Quantum cosmic models and thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F; Rozas-Fernandez, Alberto [Colina de los Chopos, Centro de Fisica ' Miguel A Catalan' , Instituto de Fisica Fundamental, Consejo Superior de Investigaciones CientIficas, Serrano 121, 28006 Madrid (Spain)], E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es, E-mail: a.rozas@cfmac.csic.es

    2008-09-07

    The current accelerating phase of the evolution of the universe is considered by constructing the most economical cosmic models that use just general relativity and some dominating quantum effects associated with the probabilistic description of quantum physics. Two such models are explicitly analyzed. They are based on the existence of a sub-quantum potential and correspond to a generalization of the spatially flat exponential model of de Sitter space. The thermodynamics of these two cosmic solutions is discussed, using the second principle as a guide to choose which among the two is more feasible. The paper also discusses the relativistic physics on which the models are based, their holographic description, some implications from the classical energy conditions and an interpretation of dark energy in terms of the entangled energy of the universe.

  6. Thermodynamic modeling of complex systems

    DEFF Research Database (Denmark)

    Liang, Xiaodong

    been developed, which has avoided the numerical pitfalls of having more than three volume roots in the real application range. It has been shown that it is possible to directly use the original PC-SAFT parameters with the new universal constants for the systems considered in this thesis. Finally...... after an oil spill. Engineering thermodynamics could be applied in the state-of-the-art sonar products through advanced artificial technology, if the speed of sound, solubility and density of oil-seawater systems could be satisfactorily modelled. The addition of methanol or glycols into unprocessed well...... streams during subsea pipelines is necessary to inhibit gas hydrate formation, and the offshore reservoirs often mean complicated temperature and pressure conditions. Accurate description of the phase behavior and thermalphysical properties of complex systems containing petroleum fluids and polar...

  7. Thermodynamic properties of Dynes superconductors

    Science.gov (United States)

    Herman, František; Hlubina, Richard

    2018-01-01

    The tunneling density of states in dirty s -wave superconductors is often well described by the phenomenological Dynes formula. Recently we have shown that this formula can be derived, within the coherent potential approximation, for superconductors with simultaneously present pair-conserving and pair-breaking impurity scattering. Here we demonstrate that the theory of such so-called Dynes superconductors is thermodynamically consistent. We calculate the specific heat and critical field of the Dynes superconductors, and we show that their gap parameter, specific heat, critical field, and penetration depth exhibit power-law scaling with temperature in the low-temperature limit. We also show that in the vicinity of a coupling-constant-controlled superconductor to normal metal transition, the Homes law is replaced by a different, pair-breaking-dominated scaling law.

  8. Modeling the thermodynamics of QCD

    Energy Technology Data Exchange (ETDEWEB)

    Hell, Thomas

    2010-07-26

    Strongly interacting (QCD) matter is expected to exhibit a multifaceted phase structure: a hadron gas at low temperatures, a quark-gluon plasma at very high temperatures, nuclear matter in the low-temperature and high-density region, color superconductors at asymptotically high densities. Most of the conjectured phases cannot yet be scrutinized by experiments. Much of the present picture - particularly concerning the intermediate temperature and density area of the phase diagram of QCD matter - is based on model calculations. Further insights come from Lattice-QCD computations. The present thesis elaborates a nonlocal covariant extension of the Nambu and Jona-Lasinio (NJL) model with built-in constraints from the running coupling of QCD at high-momentum and instanton physics at low-momentum scales. We present this model for two and three quark flavors (in the latter case paying particular attention to the axial anomaly). At finite temperatures and densities, gluon dynamics is incorporated through a gluonic background field, expressed in terms of the Polyakov loop (P). The thermodynamics of this nonlocal PNJL model accounts for both chiral and deconfinement transitions. We obtain results in mean-field approximation and beyond, including additional pionic and kaonic contributions to the chiral condensate, the pressure and other thermodynamic quantities. Finally, the nonlocal PNJL model is applied to the finite-density region of the QCD phase diagram; for three quark flavors we investigate, in particular, the dependence of the critical point appearing in the models on the axial anomaly. The thesis closes with a derivation of the nonlocal PNJL model from first principles of QCD. (orig.)

  9. Bars and boxy/peanut bulges in thin and thick discs. I. Morphology and line-of-sight velocities of a fiducial model

    Science.gov (United States)

    Fragkoudi, F.; Di Matteo, P.; Haywood, M.; Gómez, A.; Combes, F.; Katz, D.; Semelin, B.

    2017-10-01

    We explore trends in the morphology and line-of-sight (los) velocity of stellar populations in the inner regions of disc galaxies using N-body simulations with a thin (kinematically cold) and a thick (kinematically hot) disc which form a bar and a boxy/peanut (b/p) bulge. The bar in the thin disc component is 50% stronger than the thick disc bar and is more elongated, with an axis ratio almost half that of the thick disc bar. The thin disc b/p bulge has a pronounced X-shape, while the thick disc b/p is weaker with a rather boxy shape. This leads to the signature of the b/p bulge in the thick disc being weaker and further away from the plane than in the thin disc. Regarding the kinematics, we find that the los velocity of thick disc stars in the outer parts of the b/p bulge can be higher than that of thin disc stars, by up to 40% and 20% for side-on and Milky Way-like orientations of the bar, respectively. This is due to the different orbits followed by thin and thick disc stars in the bar-b/p region, which are affected by two factors. First, thin disc stars are trapped more efficiently in the bar-b/p instability and thus lose more angular momentum than their thick disc counterparts and second, thick disc stars have large radial excursions and therefore stars from large radii with high angular momenta can be found in the bar region. We also find that the difference between the los velocities of the thin and thick disc in the b/p bulge (Δvlos) correlates with the initial difference between the radial velocity dispersions of the two discs (Δσ). We therefore conclude that stars in the bar-b/p bulge will have considerably different morphologies and kinematics depending on the kinematic properties of the disc population they originate from.

  10. Glycosylation and thermodynamic versus kinetic stability of horseradish peroxidase

    DEFF Research Database (Denmark)

    Tams, J.W.; Welinder, Karen G.

    1998-01-01

    Glycoprotein stability, glycoprotein unfolding, horseradish peroxidase, thermodynamic stability, kinetik stability......Glycoprotein stability, glycoprotein unfolding, horseradish peroxidase, thermodynamic stability, kinetik stability...

  11. [Clinical consequences of sarcopenia].

    Science.gov (United States)

    Serra Rexach, J A

    2006-05-01

    The concept of sarcopenia implies loss of muscle mass and function. It is a condition that accompanies aging, although it not always has clinical consequences. It is produced by many factors: nervous system (loss of alpha motor units in the spinal cord), muscular (loss of muscle quality and mass), humoral (decrease in anabolic hormones such as testosterone, estrogens, GH, and increase of several interleukines), and life style (physical activity). The main clinical consequences of sarcopenia relate with functional independence. Thus, the sarcopenic elderly has greater difficulty walking, or do it more slowly, climbing up stairs, or doing basic daily living activities. These difficulties increase the risk for falls and, thus, fractures. They also affect bone formation, glucose tolerance, and body temperature regulation. Besides, dependency is a mortality risk factor.

  12. Virtual reality - aesthetic consequences

    OpenAIRE

    Benda, Lubor

    2013-01-01

    In the present work we study aesthetic consequences of virtual reality. Exploring the fringe between fictional and virtual is one of the key goals, that will be achieved through etymologic and technologic definition of both fiction and virtual reality, fictional and virtual worlds. Both fiction and virtual reality will be then studied from aesthetic distance and aesthetic pleasure point of view. At the end, we will see the main difference as well as an common grounds between fiction and virtu...

  13. The formation of bulges and black holes: lessons from a census of active galaxies in the SDSS.

    Science.gov (United States)

    Kauffmann, Guinevere; Heckman, Timothy M

    2005-03-15

    We examine the relationship between galaxies, supermassive black holes and AGN using a sample of 23,000 narrow-emission-line ('type 2') active galactic nuclei (AGN) drawn from a sample of 123,000 galaxies from the Sloan Digital Sky Survey. We have studied how AGN host properties compare with those of normal galaxies and how they depend on the luminosity of the active nucleus. We find that AGN reside in massive galaxies and have distributions of sizes and concentrations that are similar to those of the early-type galaxies in our sample. The host galaxies of low-luminosity AGN have stellar populations similar to normal early types. The hosts of high- luminosity AGN have much younger mean stellar ages, and a significant fraction have experienced recent starbursts. High-luminosity AGN are also found in lower-density environments. We then use the stellar velocity dispersions of the AGN hosts to estimate black hole masses and their [OIII]lambda5007 emission-line luminosities to estimate black hole accretion rates. We find that the volume averaged ratio of star formation to black hole accretion is approximately 1000 for the bulge-dominated galaxies in our sample. This is remarkably similar to the observed ratio of stellar mass to black hole mass in nearby bulges. Most of the present-day black hole growth is occurring in black holes with masses less than 3 x 10(7)M(3). Our estimated accretion rates imply that low-mass black holes are growing on a time-scale that is comparable with the age of the Universe. Around 50% this growth takes place in AGN that are radiating within a factor of five of the Eddington luminosity. Such systems are rare, making up only 0.2% of the low-mass black hole population at the present day. The remaining growth occurs in lower luminosity AGN. The growth time-scale increases by more than an order of magnitude for the most massive black holes in our sample. We conclude that the evolution of the AGN luminosity function documented in recent optical

  14. Phenomenological consequences of supersymmetry

    Energy Technology Data Exchange (ETDEWEB)

    Hinchliffe, I.; Littenberg, L.

    1982-01-01

    This report deals with the phenomenological consequences of supersymmetric theories, and with the implications of such theories for future high energy machines. It is concerned only with high energy predictions of supersymmetry; low energy consequences (for example in the K/sub o/anti K/sub o/ system) are discussed in the context of future experiments by another group, and will be mentioned briefly only in the context of constraining existing models. However a brief section is included on the implication for proton decay, although detailed experimental questions are not discussed. The report is organized as follows. Section I consists of a brief review of supersymmetry and the salient features of existing supersymmetric models; this section can be ignored by those familiar with such models since it contains nothing new. Section 2 deals with the consequences for nucleon decay of SUSY. The remaining sections then discuss the physics possibilities of various machines; e anti e in Section 3, ep in Section 4, pp (or anti pp) colliders in Section 5 and fixed target hadron machines in Section 6.

  15. Econophysics and bio-chemical engineering thermodynamics: The exergetic analysis of a municipality

    Science.gov (United States)

    Lucia, Umberto

    2016-11-01

    Exergy is a fundamental quantity because it allows us to obtain information on the useful work obtainable in a process. The analyses of irreversibility are important not only in the design and development of the industrial devices, but also in fundamental thermodynamics and in the socio-economic analysis of municipality. Consequently, the link between entropy and exergy is discussed in order to link econophysics to the bio-chemical engineering thermodynamics. Last, this link holds to the fundamental role of fluxes and to the exergy exchanged in the interaction between the system and its environment. The result consists in a thermodynamic approach to the analysis of the unavailability of the economic, productive or social systems. The unavailability is what the system cannot use in relation to its internal processes. This quantity result is interesting also as a support to public manager for economic decisions. Here, the Alessandria Municipality is analyzed in order to highlight the application of the theoretical results.

  16. THERMODYNAMIC ASSESSMENT OF ANIONIC LIGANDS ...

    African Journals Online (AJOL)

    DJFLEX

    2010-06-30

    Jun 30, 2010 ... ion. This brings about repulsion between the adsorbent and positively charged ion and consequently a reduction in the amount of heavy metal adsorbed at lower pH. (Lee, 1999). The effectiveness of the anionic ligands in the removal of heavy metal ions from aqueous solution seems to be low for the EDTA.

  17. Thermodynamic properties of uranium--mercury system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T.S.

    1979-01-01

    The EMF values in the fused salt cells of the type U(..cap alpha..)/KCl--LiCl--BaCl/sub 2/ eutectic, UCl/sub 3//U--Hg alloy, for the different two-phase alloys in the uranium--mercury system have been measured and the thermodynamic properties of this system have been calculated. These calculated values are in good agreement with values based on mercury vapor pressure measurements made by previous investigators. The inconsistency of the thermodynamic properties with the phase diagram determined by Frost are also confirmed. A tentative phase diagram based on the thermodynamic properties measured in this work was constructed.

  18. Introduction to physics mechanics, hydrodynamics thermodynamics

    CERN Document Server

    Frauenfelder, P

    2013-01-01

    Introduction of Physics: Mechanics , Hydrodynamics, Thermodynamics covers the principles of matter and its motion through space and time, as well as the related concepts of energy and force. This book is composed of eleven chapters, and begins with an introduction to the basic principles of mechanics, hydrodynamics, and thermodynamics. The subsequent chapters deal with the statics of rigid bodies and the dynamics of particles and rigid bodies. These topics are followed by discussions on elasticity, mechanics of fluids, the basic concept of thermodynamic, kinetic theory, and crystal structure o

  19. Thermodynamic Formalism and Applications to Dimension Theory

    CERN Document Server

    Barreira, Luis

    2011-01-01

    This self-contained monograph presents a unified exposition of the thermodynamic formalism and some of its main extensions, with emphasis on the relation to dimension theory and multifractal analysis of dynamical systems. In particular, the book considers three different flavors of the thermodynamic formalism, namely nonadditive, subadditive, and almost additive, and provides a detailed discussion of some of the most significant results in the area, some of them quite recent. It also includes a discussion of the most substantial applications of these flavors of the thermodynamic formalism to d

  20. Thermodynamic Volume in AdS/CFT

    Science.gov (United States)

    Kim, Kyung Kiu; Ahn, Byoungjoon

    2018-01-01

    In this note, we study on extended thermodynamics of AdS black holes by varying cosmological constant. We found and discussed pressure and volume of both bulk and boundary physics through AdS/CFT correspondence. In particular, we derive the relation between thermodynamic volume and a chemical potential for M2 brane dual to four dimensional AdS space. In addition, we show that thermodynamic volume of hyperbolic black hole is related to `entanglement pressure' coming from a generalized first law of entanglement entropy.

  1. Thermodynamics of cosmological matter creation

    Science.gov (United States)

    Prigogine, I.; Geheniau, J.; Gunzig, E.; Nardone, P.

    1988-01-01

    A type of cosmological history that includes large-scale entropy production is proposed. These cosmologies are based on reinterpretation of the matter-energy stress tensor in Einstein's equations. This modifies the usual adiabatic energy conservation laws, thereby including irreversible matter creation. This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents. This point of view results from consideration of the thermodynamics of open systems in the framework of cosmology. It is shown that the second law of thermodynamics requires that space-time transforms into matter, while the inverse transformation is forbidden. It appears that the usual initial singularity associated with the big bang is structurally unstable with respect to irreversible matter creation. The corresponding cosmological history therefore starts from an instability of the vacuum rather than from a singularity. This is exemplified in the framework of a simple phenomenological model that leads to a three-stage cosmology: the first drives the cosmological system from the initial instability to a de Sitter regime, and the last connects with the usual matter-radiation Robertson-Walker universe. Matter as well as entropy creation occurs during the first two stages, while the third involves the traditional cosmological evolution. A remarkable fact is that the de Sitter stage appears to be an attractor independent of the initial fluctuation. This is also the case for all the physical predictions involving the present Robertson-Walker universe. Most results obtained previously, in the framework of quantum field theory, can now be obtained on a macroscopic basis. It is shown that this description leads quite naturally to the introduction of primeval black holes as the intermediate stage between the Minkowski vacuum and the present matter-radiation universe. The instability at the origin of the universe is the result of fluctuations of the

  2. Thermodynamics of cosmological matter creation.

    Science.gov (United States)

    Prigogine, I; Geheniau, J; Gunzig, E; Nardone, P

    1988-10-01

    A type of cosmological history that includes large-scale entropy production is proposed. These cosmologies are based on reinterpretation of the matter-energy stress tensor in Einstein's equations. This modifies the usual adiabatic energy conservation laws, thereby including irreversible matter creation. This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents. This point of view results from consideration of the thermodynamics of open systems in the framework of cosmology. It is shown that the second law of thermodynamics requires that space-time transforms into matter, while the inverse transformation is forbidden. It appears that the usual initial singularity associated with the big bang is structurally unstable with respect to irreversible matter creation. The corresponding cosmological history therefore starts from an instability of the vacuum rather than from a singularity. This is exemplified in the framework of a simple phenomenological model that leads to a three-stage cosmology: the first drives the cosmological system from the initial instability to a de Sitter regime, and the last connects with the usual matter-radiation Robertson-Walker universe. Matter as well as entropy creation occurs during the first two stages, while the third involves the traditional cosmological evolution. A remarkable fact is that the de Sitter stage appears to be an attractor independent of the initial fluctuation. This is also the case for all the physical predictions involving the present Robertson-Walker universe. Most results obtained previously, in the framework of quantum field theory, can now be obtained on a macroscopic basis. It is shown that this description leads quite naturally to the introduction of primeval black holes as the intermediate stage between the Minkowski vacuum and the present matter-radiation universe. The instability at the origin of the universe is the result of fluctuations of the

  3. Using Long-term Millisecond Pulsar Timing to Obtain Physical Characteristics of the Bulge Globular Cluster Terzan 5

    Science.gov (United States)

    Prager, Brian J.; Ransom, Scott M.; Freire, Paulo C. C.; Hessels, Jason W. T.; Stairs, Ingrid H.; Arras, Phil; Cadelano, Mario

    2017-08-01

    Over the past decade, the discovery of three unique stellar populations and a large number of confirmed pulsars within the globular cluster Terzan 5 has raised questions over its classification. Using the long-term radio pulsar timing of 36 ms pulsars in the cluster core, we provide new measurements of key physical properties of the system. As Terzan 5 is located within the galactic bulge, stellar crowding and reddening make optical and near-infrared observations difficult. Pulsar accelerations, however, allow us to study the intrinsic characteristics of the cluster independent of reddening and stellar crowding and probe the mass density profile without needing to quantify the mass-to-light ratio. Relating the spin and orbital periods of each pulsar to the acceleration predicted by a King model, we find a core density of {1.58}-0.13+0.13 × 106 {M}⊙ pc-3, a core radius of {0.16}-0.01+0.01 pc, a pulsar density profile of n\\propto {r}-{3.14-0.53+0.52}, and a total mass of {M}{{T}}({R}\\perp pulsars were formed via electron-capture supernovae or exist in a core full of heavy white dwarfs and hard binaries. Finally, we provide an upper limit for the mass of a possible black hole at the core of the cluster of {M}{BH}≃ 3× {10}4 {M}⊙ .

  4. Formation of Supermassive Black Holes in Galactic Bulges: A Rotating Collapse Model Consistent with the M(sub BH-sigma) Relation

    Science.gov (United States)

    Adams, Fred C.; Graff, David S.; Mbonye, Manasse; Richstone, Douglas O.

    2003-01-01

    Motivated by the observed correlation between black hole masses M(sub BH) and the velocity dispersion sigma of host galaxies, we develop a theoretical model of black hole formation in galactic bulges (this paper generalizes an earlier ApJ Letter). The model assumes an initial state specified by a uniform rotation rate OMEGA and a density distribution of the form rho = a(sup 2)(sub eff)per2piGR(sup 2)(so that a(sub eff)is an effective transport speed). The black hole mass is determined when the centrifugal radius of the collapse flow exceeds the capture radius of the central black hole (for Schwarzschild geometry). This model reproduces the observed correlation between the estimated black hole masses and the velocity dispersions of galactic bulges, i.e., M(sub BH) approximately equal to 10(sup 8) solar mass(sigma per 200 kilometers per second)(sup 4) where sigma = the square root of 2a(sub eff). To obtain this normalization, the rotation rate OMEGA approximately equal to 2 x 10(exp -15) rad per second. The model also defines a bulge mass scale M(sub B). If we identify the scale M(sub B) with the bulge mass, the model determines the ratio mu(sub B) of black hole mass to the host mass: mu(sub B) approximately equal to 0.0024(sigma per 200 kilometer per second), again in reasonable agreement with observed values. In this scenario, supermassive black holes form quickly (in approximately 10(exp 5) yr) and are born rapidly rotating (with a per M approximately 0.9). This paper also shown how these results depend on the assumed initial conditions; the most important quantity is the initial distribution of specific angular momentum in the precollapse state.

  5. INTEGRAL Galactic Bulge monitoring: transient activity from KS 1741-293, MXB 1730-335, and IGR J17498-2921

    DEFF Research Database (Denmark)

    Chenevez, Jérôme; Brandt, Søren; Kuulkers, E.

    2011-01-01

    As part of its regular monitoring of the Galactic Bulge (see ATel #438) INTEGRAL observed this region of the sky on September 13, 2011, between UTC 9:14:50 and 12:56:26. Both the JEM-X and the IBIS/ISGRI instruments detect the transient neutron star low-mass X-ray binary KS 1741-293 at the follow...

  6. Thermodynamics of quantum spacetime histories

    Science.gov (United States)

    Smolin, Lee

    2017-11-01

    We show that the simplicity constraints, which define the dynamics of spin foam models, imply, and are implied by, the first law of thermodynamics, when the latter is applied to causal diamonds in the quantum spacetime. This result reveals an intimate connection between the holographic nature of gravity, as reflected by the Bekenstein entropy, and the fact that general relativity and other gravitational theories can be understood as constrained topological field theories. To state and derive this correspondence we describe causal diamonds in the causal structure of spin foam histories and generalize arguments given for the near horizon region of black holes by Frodden, Gosh and Perez [Phys. Rev. D 87, 121503 (2013); , 10.1103/PhysRevD.87.121503Phys. Rev. D 89, 084069 (2014); , 10.1103/PhysRevD.89.084069Phys. Rev. Lett. 107, 241301 (2011); , 10.1103/PhysRevLett.107.241301Phys. Rev. Lett.108, 169901(E) (2012)., 10.1103/PhysRevLett.108.169901] and Bianchi [arXiv:1204.5122.]. This allows us to apply a recent argument of Jacobson [Phys. Rev. Lett. 116, 201101 (2016).10.1103/PhysRevLett.116.201101] to show that if a spin foam history has a semiclassical limit described in terms of a smooth metric geometry, that geometry satisfies the Einstein equations. These results suggest also a proposal for a quantum equivalence principle.

  7. Thermodynamics of Quantum Feedback Cooling

    Directory of Open Access Journals (Sweden)

    Pietro Liuzzo-Scorpo

    2016-02-01

    Full Text Available The ability to initialize quantum registers in pure states lies at the core of many applications of quantum technologies, from sensing to quantum information processing and computation. In this paper, we tackle the problem of increasing the polarization bias of an ensemble of two-level register spins by means of joint coherent manipulations, involving a second ensemble of ancillary spins and energy dissipation into an external heat bath. We formulate this spin refrigeration protocol, akin to algorithmic cooling, in the general language of quantum feedback control, and identify the relevant thermodynamic variables involved. Our analysis is two-fold: on the one hand, we assess the optimality of the protocol by means of suitable figures of merit, accounting for both its work cost and effectiveness; on the other hand, we characterise the nature of correlations built up between the register and the ancilla. In particular, we observe that neither the amount of classical correlations nor the quantum entanglement seem to be key ingredients fuelling our spin refrigeration protocol. We report instead that a more general indicator of quantumness beyond entanglement, the so-called quantum discord, is closely related to the cooling performance.

  8. Thermodynamics of superconducting quantum metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Dallaire-Demers, Pierre-Luc; Wilhelm-Mauch, Frank [Universitaet des Saarlandes (Germany)

    2015-07-01

    Left-handed matematerials are capacitively coupled layers of inductive pieces of conductors. These systems are well studied in the context of microwave metamaterials but their full quantum description or their embedding in highly correlated materials like superconductors are still an open problem. Notably, they are known to have a Van Hove singularity in the density of states at low energy and high pseudo-momentum that could effectively couple and condense Cooper pairs. The goal of this research is to analyze the thermodynamical properties of the order parameter of stacked layers of superconductors with a small repulsive Coulomb interaction. A 3D toy model of such a material is mapped to a Fermi-Hubbard lattice. The temperature dependent anomalous correlation functions are computed variationally from a self-energy functional of a small cluster where inter-cluster tunneling is treated perturbatively. The effect of the repulsive interaction on the Cooper pairs binding can then be seen from the momentum distribution of the condensation amplitude. Such a material could potentially be realized with optical lattices or nanoscaled superconductors.

  9. Tuning Optical Signatures of Single- and Few-Layer MoS2 by Blown-Bubble Bulge Straining up to Fracture.

    Science.gov (United States)

    Yang, Rui; Lee, Jaesung; Ghosh, Souvik; Tang, Hao; Sankaran, R Mohan; Zorman, Christian A; Feng, Philip X-L

    2017-08-09

    Emerging atomic layer semiconducting crystals such as molybdenum disulfide (MoS2) are promising candidates for flexible electronics and strain-tunable devices due to their ultrahigh strain limits (up to ∼20-30%) and strain-tunable bandgaps. However, high strain levels, controllable isotropic and anisotropic biaxial strains in single- and few-layer MoS2 on device-oriented flexible substrates permitting convenient and fast strain tuning, remain unexplored. Here, we demonstrate a "blown-bubble" bulge technique for efficiently applying large strains to atomic layer MoS2 devices on a flexible substrate. As the strain increases via bulging, we achieve continuous tuning of Raman and photoluminescence (PL) signatures in single- and few-layer MoS2, including splitting of Raman peaks. With proper clamping of the MoS2 crystals, we apply up to ∼9.4% strain in the flexible substrate, which causes a doubly clamped single-layer MoS2 to fracture at 2.2-2.6% strain measured by PL and 2.9-3.5% strain measured by Raman spectroscopy. This study opens new pathways for exploiting 2D semiconductors on stretchable substrates for flexible electronics, mechanical transducers, tunable optoelectronics, and biomedical transducers on curved and bulging surfaces.

  10. Normal black holes in bulge-less galaxies: the largely quiescent, merger-free growth of black holes over cosmic time

    Science.gov (United States)

    Martin, G.; Kaviraj, S.; Volonteri, M.; Simmons, B. D.; Devriendt, J. E. G.; Lintott, C. J.; Smethurst, R. J.; Dubois, Y.; Pichon, C.

    2018-02-01

    Understanding the processes that drive the formation of black holes (BHs) is a key topic in observational cosmology. While the observed MBH-MBulge correlation in bulge-dominated galaxies is thought to be produced by major mergers, the existence of a MBH-M⋆ relation, across all galaxy morphological types, suggests that BHs may be largely built by secular processes. Recent evidence that bulge-less galaxies, which are unlikely to have had significant mergers, are offset from the MBH-MBulge relation, but lie on the MBH-M⋆ relation, has strengthened this hypothesis. Nevertheless, the small size and heterogeneity of current datasets, coupled with the difficulty in measuring precise BH masses, makes it challenging to address this issue using empirical studies alone. Here, we use Horizon-AGN, a cosmological hydrodynamical simulation to probe the role of mergers in BH growth over cosmic time. We show that (1) as suggested by observations, simulated bulge-less galaxies lie offset from the main MBH-MBulge relation, but on the MBH-M⋆ relation, (2) the positions of galaxies on the MBH-M⋆ relation are not affected by their merger histories and (3) only ˜35 per cent of the BH mass in today's massive galaxies is directly attributable to merging - the majority (˜65 per cent) of BH growth, therefore, takes place gradually, via secular processes, over cosmic time.

  11. [Thermodynamics of life from the point of view of technical thermodynamics and exergy].

    Science.gov (United States)

    Grassmann, P

    1984-07-01

    All living beings are, from the thermodynamic point of view, open, well regulated, and optimized systems with considerable internal irreversibilities. However scientific research is mainly based on closed systems. The theory of open systems is very well developed in engineering thermodynamics. Here the concept of "exergy"--the thermodynamic potential related to given surroundings--clearly distinguishes between the two concepts of the word "energy".

  12. Universalities of thermodynamic signatures in topological phases

    NARCIS (Netherlands)

    Kempkes, S. N.; Quelle, A.; de Morais Smith, C.

    2016-01-01

    Topological insulators (superconductors) are materials that host symmetry-protected metallic edge states in an insulating (superconducting) bulk. Although they are well understood, a thermodynamic description of these materials remained elusive, firstly because the edges yield a non-extensive

  13. Thermodynamic Products in the Extended Phase Space

    CERN Document Server

    Pradhan, Parthapratim

    2016-01-01

    We have examined the thermodynamic properties of spherically symmetric charged-AdS black hole, charged AdS BH surrounded by quintessence and charged AdS BH in $f(R)$ gravity in the extended phase-space. Where the cosmological constant should be treated as thermodynamic pressure and its conjugate parameter as thermodynamic volume. Then they should behave as a analog of Van der Waal like systems. In the extended phase space we have calculated the \\emph{entropy product} and \\emph{thermodynamic volume product} of all horizons. The mass(or enthalpy) independent nature of the said products signals they are "universal" quantities. Various types of pictorial diagram of the specific heat is given. The divergence of the specific heat indicates that the second order phase transition occurs under certain condition.

  14. Metrics and Energy Landscapes in Irreversible Thermodynamics

    Directory of Open Access Journals (Sweden)

    Bjarne Andresen

    2015-09-01

    Full Text Available We describe how several metrics are possible in thermodynamic state space but that only one, Weinhold’s, has achieved widespread use. Lengths calculated based on this metric have been used to bound dissipation in finite-time (irreversible processes be they continuous or discrete, and described in the energy picture or the entropy picture. Examples are provided from thermodynamics of heat conversion processes as well as chemical reactions. Even losses in economics can be bounded using a thermodynamic type metric. An essential foundation for the metric is a complete equation of state including all extensive variables of the system; examples are given. Finally, the second law of thermodynamics imposes convexity on any equation of state, be it analytical or empirical.

  15. Quantum thermodynamics of general quantum processes.

    Science.gov (United States)

    Binder, Felix; Vinjanampathy, Sai; Modi, Kavan; Goold, John

    2015-03-01

    Accurately describing work extraction from a quantum system is a central objective for the extension of thermodynamics to individual quantum systems. The concepts of work and heat are surprisingly subtle when generalizations are made to arbitrary quantum states. We formulate an operational thermodynamics suitable for application to an open quantum system undergoing quantum evolution under a general quantum process by which we mean a completely positive and trace-preserving map. We derive an operational first law of thermodynamics for such processes and show consistency with the second law. We show that heat, from the first law, is positive when the input state of the map majorizes the output state. Moreover, the change in entropy is also positive for the same majorization condition. This makes a strong connection between the two operational laws of thermodynamics.

  16. Non-Equilibrium Thermodynamics in Multiphase Flows

    CERN Document Server

    Mauri, Roberto

    2013-01-01

    Non-equilibrium thermodynamics is a general framework that allows the macroscopic description of irreversible processes. This book introduces non-equilibrium thermodynamics and its applications to the rheology of multiphase flows. The subject is relevant to graduate students in chemical and mechanical engineering, physics and material science. This book is divided into two parts. The first part presents the theory of non-equilibrium thermodynamics, reviewing its essential features and showing, when possible, some applications. The second part of this book deals with how the general theory can be applied to model multiphase flows and, in particular, how to determine their constitutive relations. Each chapter contains problems at the end, the solutions of which are given at the end of the book. No prior knowledge of statistical mechanics is required; the necessary prerequisites are elements of transport phenomena and on thermodynamics. “The style of the book is mathematical, but nonetheless it remains very re...

  17. Thermodynamics of sedimentation in paucidisperse systems

    NARCIS (Netherlands)

    Hooyman, G.J.

    1956-01-01

    The previously given treatment of sedimentation phenomena in monodisperse uncharged systems with the help of thermodynamics of irreversible processes is extended to paucidisperse systems. The sedimentation rates of the components are derived by neglecting transverse effects and by introducing the

  18. Fluctuations of Intensive Quantities in Statistical Thermodynamics

    Directory of Open Access Journals (Sweden)

    Artur E. Ruuge

    2013-11-01

    Full Text Available In phenomenological thermodynamics, the canonical coordinates of a physical system split in pairs, with each pair consisting of an extensive quantity and an intensive one. In the present paper, the quasithermodynamic fluctuation theory of a model system of a large number of oscillators is extended to statistical thermodynamics based on the idea of perceiving the fluctuations of intensive variables as the fluctuations of specific extensive ones in a “thermodynamically dual” system. The extension is motivated by the symmetry of the problem in the context of an analogy with quantum mechanics, which is stated in terms of a generalized Pauli problem for the thermodynamic fluctuations. The doubled Boltzmann constant divided by the number of particles plays a similar role as the Planck constant.

  19. The entropy principle thermodynamics for the unsatisfied

    CERN Document Server

    Thess, André

    2011-01-01

    Entropy is the most important and the most difficult to understand term of thermodynamics. This book helps make this key concept understandable. It includes seven illustrative examples of applications of entropy, which are presented step by step.

  20. Thermodynamics of Computational Copying in Biochemical Systems

    Science.gov (United States)

    Ouldridge, Thomas E.; Govern, Christopher C.; ten Wolde, Pieter Rein

    2017-04-01

    Living cells use readout molecules to record the state of receptor proteins, similar to measurements or copies in typical computational devices. But is this analogy rigorous? Can cells be optimally efficient, and if not, why? We show that, as in computation, a canonical biochemical readout network generates correlations; extracting no work from these correlations sets a lower bound on dissipation. For general input, the biochemical network cannot reach this bound, even with arbitrarily slow reactions or weak thermodynamic driving. It faces an accuracy-dissipation trade-off that is qualitatively distinct from and worse than implied by the bound, and more complex steady-state copy processes cannot perform better. Nonetheless, the cost remains close to the thermodynamic bound unless accuracy is extremely high. Additionally, we show that biomolecular reactions could be used in thermodynamically optimal devices under exogenous manipulation of chemical fuels, suggesting an experimental system for testing computational thermodynamics.

  1. Thermodynamic considerations in renal separation processes

    National Research Council Canada - National Science Library

    Robert H Louw; David M Rubin; David Glasser; Robyn F R Letts; Diane Hildebrandt

    2017-01-01

    .... This study uses a thermodynamic analysis to evaluate the minimum work requirements for urine production in the human kidney and provide a new perspective on the energy costs of urine production...

  2. A note on the relations between thermodynamics, energy definitions and Friedmann equations

    Science.gov (United States)

    Moradpour, H.; Nunes, Rafael C.; Abreu, Everton M. C.; Neto, Jorge Ananias

    2017-04-01

    We investigate the relation between the Friedmann and thermodynamic pressure equations, through solving the Friedmann and thermodynamic pressure equations simultaneously. Our investigation shows that a perfect fluid, as a suitable solution for the Friedmann equations leading to the standard modeling of the universe expansion history, cannot simultaneously satisfy the thermodynamic pressure equation and those of Friedmann. Moreover, we consider various energy definitions, such as the Komar mass, and solve the Friedmann and thermodynamic pressure equations simultaneously to get some models for dark energy fluids. The cosmological consequences of obtained solutions are also addressed. Our results indicate that some of obtained solutions may unify the dominated fluid in both the primary inflationary and current accelerating eras into one model. In addition, by taking into account a cosmic fluid of a known equation of state (EoS), and combining it with the Friedmann and thermodynamic pressure equations, we obtain the corresponding energy of these cosmic fluids and face their limitations. Finally, we point out the cosmological features of this cosmic fluid and also study its observational constraints.

  3. Universalities of thermodynamic signatures in topological phases

    OpenAIRE

    S. N. Kempkes; Quelle, A.; de Morais Smith, C.

    2016-01-01

    Topological insulators (superconductors) are materials that host symmetry-protected metallic edge states in an insulating (superconducting) bulk. Although they are well understood, a thermodynamic description of these materials remained elusive, firstly because the edges yield a non-extensive contribution to the thermodynamic potential, and secondly because topological field theories involve non-local order parameters, and cannot be captured by the Ginzburg-Landau formalism. Recently, this ch...

  4. Qualitative and quantitative reasoning about thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Skorstad, G.; Forbus, K. (Univ. of Illinois at Urbana-Champaign, IL (US))

    1989-01-01

    This paper shows how qualitative process theory can be used to express concepts of engineering thermodynamics. In particular, the authors describe how to integrate qualitative and quantitative knowledge to solve textbook problems involving thermodynamic cycles, such as gas turbine plants and steam power plants. These ideas have been implemented in a program called SCHISM. The authors describe its analysis of a sample textbook problem and discuss plans for future work.

  5. Tables of thermodynamic properties of sodium

    Energy Technology Data Exchange (ETDEWEB)

    Fink, J.K.

    1982-06-01

    The thermodynamic properties of saturated sodium, superheated sodium, and subcooled sodium are tabulated as a function of temperature. The temperature ranges are 380 to 2508 K for saturated sodium, 500 to 2500 K for subcooled sodium, and 400 to 1600 K for superheated sodium. Tabulated thermodynamic properties are enthalpy, heat capacity, pressure, entropy, density, instantaneous thermal expansion coefficient, compressibility, and thermal pressure coefficient. Tables are given in SI units and cgs units.

  6. Chemical engineering and thermodynamics using Mat lab

    Energy Technology Data Exchange (ETDEWEB)

    Kim Heon; Kim, Moon Gap; Lee, Hak Yeong; Yeo, Yeong Gu; Ham, Seong Won

    2002-02-15

    This book consists of twelve chapters and four appendixes about chemical engineering and thermodynamics using Mat lab, which deals with introduction, energy budget, entropy, thermodynamics process, generalization on any fluid, engineering equation of state for PVT properties, deviation of the function, phase equilibrium of pure fluid, basic of multicomponent, phase equilibrium of compound by state equation, activity model and reaction system. The appendixes is about summary of computer program, related mathematical formula and material property of pure component.

  7. Thermodynamical analysis of human thermal comfort

    OpenAIRE

    Prek, Matjaž

    2015-01-01

    Traditional methods of human thermal comfort analysis are based on the first law of thermodynamics. These methods use an energy balance of the human body to determine heat transfer between the body and its environment. By contrast, the second law of thermodynamics introduces the useful concept of exergy. It enables the determination of the exergy consumption within the human body dependent on human and environmental factors. Human body exergy consumption varies with the combination of environ...

  8. Molecular thermodynamics using fluctuation solution theory

    DEFF Research Database (Denmark)

    Ellegaard, Martin Dela

    to relevant experimental data is limited. This thesis addresses the issue of generating and using simple thermodynamic models within a rigorous statistical mechanical framework, the so-called fluctuation solution theory, from which relations connecting properties and phase equilibria can be obtained....... The framework relates thermodynamic variables to molecular pair correlation functions of liquid mixtures. In this thesis, application of the framework is illustrated using two approaches: 1. Solubilities of solid solutes in mixed solvent systems are determined from fluctuation solution theory application...

  9. OPTIMAL PROCESSES IN IRREVERSIBLE THERMODYNAMICS AND MICROECONOMICS

    Directory of Open Access Journals (Sweden)

    Vladimir A. Kazakov

    2004-06-01

    Full Text Available This paper describes general methodology that allows one to extend Carnot efficiency of classical thermodynamic for zero rate processes onto thermodynamic systems with finite rate. We define the class of minimal dissipation processes and show that it represents generalization of reversible processes and determines the limiting possibilities of finite rate systems. The described methodology is then applied to microeconomic exchange systems yielding novel estimates of limiting efficiencies for such systems.

  10. An examination of the consequences in high consequence operations

    Energy Technology Data Exchange (ETDEWEB)

    Spray, S.D.; Cooper, J.A.

    1996-06-01

    Traditional definitions of risk partition concern into the probability of occurrence and the consequence of the event. Most safety analyses focus on probabilistic assessment of an occurrence and the amount of some measurable result of the event, but the real meaning of the ``consequence`` partition is usually afforded less attention. In particular, acceptable social consequence (consequence accepted by the public) frequently differs significantly from the metrics commonly proposed by risk analysts. This paper addresses some of the important system development issues associated with consequences, focusing on ``high consequence operations safety.``

  11. Thermodynamics for separation-process technology

    Energy Technology Data Exchange (ETDEWEB)

    Prausnitz, J.M.

    1995-10-01

    When contemplating or designing a separation process, every chemical engineer at once recognizes the thermodynamic boundary conditions that must be satisfied: when a mixture is continuously processed to yield at least partially purified products, energy and mass must be conserved and work must be done. In his daily tasks, a chemical engineer uses thermodynamic concepts as tacit, almost subconscious, knowledge. Thus, qualitative thermodynamics significantly informs process conception at its most fundamental level. However, quantitative design requires detailed knowledge of thermodynamic relations and physical chemistry. Most process engineers, concerned with flow sheets and economics, cannot easily command that detailed knowledge and therefore it is advantageous for them to maintain close contact with those specialists who do. Quantitative chemical thermodynamics provides an opportunity to evaluate possible separation processes not only because it may give support to the process engineer`s bold imagination but also because, when coupled with molecular models, it can significantly reduce the experimental effort required to determine an optimum choice of process alternatives. Six examples are presented to indicate the application of thermodynamics for conventional and possible future separation processes.

  12. Universalities of thermodynamic signatures in topological phases

    Science.gov (United States)

    Kempkes, S. N.; Quelle, A.; Smith, C. Morais

    2016-01-01

    Topological insulators (superconductors) are materials that host symmetry-protected metallic edge states in an insulating (superconducting) bulk. Although they are well understood, a thermodynamic description of these materials remained elusive, firstly because the edges yield a non-extensive contribution to the thermodynamic potential, and secondly because topological field theories involve non-local order parameters, and cannot be captured by the Ginzburg-Landau formalism. Recently, this challenge has been overcome: by using Hill thermodynamics to describe the Bernevig-Hughes-Zhang model in two dimensions, it was shown that at the topological phase transition the thermodynamic potential does not scale extensively due to boundary effects. Here, we extend this approach to different topological models in various dimensions (the Kitaev chain and Su-Schrieffer-Heeger model in one dimension, the Kane-Mele model in two dimensions and the Bernevig-Hughes-Zhang model in three dimensions) at zero temperature. Surprisingly, all models exhibit the same universal behavior in the order of the topological-phase transition, depending on the dimension. Moreover, we derive the topological phase diagram at finite temperature using this thermodynamic description, and show that it displays a good agreement with the one calculated from the Uhlmann phase. Our work reveals unexpected universalities and opens the path to a thermodynamic description of systems with a non-local order parameter. PMID:27929041

  13. Thermodynamic DFT analysis of natural gas.

    Science.gov (United States)

    Neto, Abel F G; Huda, Muhammad N; Marques, Francisco C; Borges, Rosivaldo S; Neto, Antonio M J C

    2017-08-01

    Density functional theory was performed for thermodynamic predictions on natural gas, whose B3LYP/6-311++G(d,p), B3LYP/6-31+G(d), CBS-QB3, G3, and G4 methods were applied. Additionally, we carried out thermodynamic predictions using G3/G4 averaged. The calculations were performed for each major component of seven kinds of natural gas and to their respective air + natural gas mixtures at a thermal equilibrium between room temperature and the initial temperature of a combustion chamber during the injection stage. The following thermodynamic properties were obtained: internal energy, enthalpy, Gibbs free energy and entropy, which enabled us to investigate the thermal resistance of fuels. Also, we estimated an important parameter, namely, the specific heat ratio of each natural gas; this allowed us to compare the results with the empirical functions of these parameters, where the B3LYP/6-311++G(d,p) and G3/G4 methods showed better agreements. In addition, relevant information on the thermal and mechanic resistance of natural gases were investigated, as well as the standard thermodynamic properties for the combustion of natural gas. Thus, we show that density functional theory can be useful for predicting the thermodynamic properties of natural gas, enabling the production of more efficient compositions for the investigated fuels. Graphical abstract Investigation of the thermodynamic properties of natural gas through the canonical ensemble model and the density functional theory.

  14. Thermodynamic analysis of resources used in manufacturing processes.

    Science.gov (United States)

    Gutowski, Timothy G; Branham, Matthew S; Dahmus, Jeffrey B; Jones, Alissa J; Thiriez, Alexandre

    2009-03-01

    In this study we use a thermodynamic framework to characterize the material and energy resources used in manufacturing processes. The analysis and data span a wide range of processes from "conventional" processes such as machining, casting, and injection molding, to the so-called "advanced machining" processes such as electrical discharge machining and abrasive waterjet machining, and to the vapor-phase processes used in semiconductor and nanomaterials fabrication. In all, 20 processes are analyzed. The results show that the intensity of materials and energy used per unit of mass of material processed (measured either as specific energy or exergy) has increased by at least 6 orders of magnitude over the past several decades. The increase of material/energy intensity use has been primarily a consequence of the introduction of new manufacturing processes, rather than changes in traditional technologies. This phenomenon has been driven by the desire for precise small-scale devices and product features and enabled by stable and declining material and energy prices over this period. We illustrate the relevance of thermodynamics (including exergy analysis) for all processes in spite of the fact that long-lasting focus in manufacturing has been on product quality--not necessarily energy/material conversion efficiency. We promote the use of thermodynamics tools for analysis of manufacturing processes within the context of rapidly increasing relevance of sustainable human enterprises. We confirm that exergy analysis can be used to identify where resources are lost in these processes, which is the first step in proposing and/or redesigning new more efficient processes.

  15. Unintended Consequences of Remittance

    Directory of Open Access Journals (Sweden)

    Adediran Daniel Ikuomola

    2015-09-01

    Full Text Available Research on migrants’ remittance in Nigeria has largely focused on the contribution to national development and economic well-being of family members. In contrast, this article explores the way in which remittance serves as potential sources of conflict within migrant households. The article investigates intra-household conflicts related to migrant remittances, revealing the contradictory and unintended consequences of remittances destabilizing cordial relationships between migrants and family members. Within the family (mainly extended families, the sharing of remittance is often accompanied with envy, distrust, and accusation of witch hunt. While improper utilization and accountability of remittances strain relationships, migrants are forced to re-strategize on how remittances get to their relatives and sometimes cut off communication and remittances with family members. Based on the qualitative data collected in Benin City (Edo State in Nigeria, the article investigates intra-household conflicts emanating from migrant remittances, from the perspectives of migrants on holidays.

  16. Medical consequences of obesity.

    Science.gov (United States)

    Lawrence, Victor J; Kopelman, Peter G

    2004-01-01

    The obese are subject to health problems directly relating to the carriage of excess adipose tissue. These problems range from arthritis, aches and pains, sleep disturbance, dyspnea on mild exertion, and excessive sweating to social stigmatization and discrimination, all of which may contribute to low quality of life and depression (Table 1). The most serious medical consequences of obesity are a result of endocrine and metabolic changes, most notably type 2 diabetes mellitus, cardiovascular disease, and increased risk of cancer. Not all obesity comorbidities are fully reversed by weight loss. The degree and duration of weight loss required may not be achievable by an individual patient. Furthermore, "weight cycling" may be more detrimental to both physical and mental health than failure to achieve weight loss targets with medical and lifestyle advice.

  17. A survey of 286 Virgo cluster galaxies at optical griz and near-IR H band: surface brightness profiles and bulge-disc decompositions

    Science.gov (United States)

    McDonald, Michael; Courteau, Stéphane; Tully, R. Brent; Roediger, Joel

    2011-07-01

    We present and g-, r-, i-, z- and H-band surface brightness profiles and bulge-disc decompositions for a morphologically broad sample of 286 Virgo Cluster Catalogue (VCC) galaxies. The H-band data come from a variety of sources including our survey of 171 VCC galaxies at the University of Hawaii (UH) 2.2-m telescope, Canada-France-Hawaii Telescope (CFHT) and United Kingdom Infrared Telescope (UKIRT), and another 115 galaxies from the Two Micron All Sky Survey (2MASS) and GOLDMine archives. The optical data for all 286 VCC galaxies were extracted from the Sloan Digital Sky Survey (SDSS) images. The H-band and the SDSS griz data were analysed in a homogeneous manner using our own software, yielding a consistent set of deep, multiband surface brightness profiles for each galaxy. Average surface brightness profiles per morphological bin were created in order to characterize the variety of galaxy light profiles across the Hubble sequence. The 1D bulge-disc decomposition parameters, as well as non-parametric galaxy measures, such as effective radius, effective surface brightness and light concentration, are presented for all 286 VCC galaxies in each of the five optical/near-infrared wavebands. The profile decompositions account for bulge and disc components, spiral arms, nucleus and atmospheric blurring. The Virgo spiral galaxy bulges typically have a Sérsic index n˜ 1, while elliptical galaxies prefer n˜ 2. No galaxy spheroid requires n > 3. The light profiles for 70 per cent of the Virgo elliptical galaxies reveal the presence of both a spheroid and disc component. A more in-depth discussion of the structural parameter trends can be found in McDonald, Courteau & Tully. The data provided here should serve as a base for studies of galaxy structure and stellar populations in the cluster environment. The galaxy light profiles and bulge-disc decomposition results are available at the Centre de Données astronomiques de Strasbourg (CDS; ) and the author's own website ().

  18. Thermodynamic properties of potassium oxides

    Energy Technology Data Exchange (ETDEWEB)

    Byker, H.J. (Montana State Univ., Bozeman); Eliezer, I.; Howald, R.C.; Ehlert, T.C.

    1979-09-01

    KO/sub 0/ /sub 5/ has been prepared by the reaction of excess potassium with KNO/sub 3/ in an effusion cell. Observations of the 2KO/sub 0/ /sub 5/ ..-->.. K/sub 2/O(g) equilibrium mass spectrometrically give a new value for the enthalpy of solid KO/sub 0/ /sub 5/, ..delta..H/sub f,298//sup 0/ = -170 +- 5 kJ mol/sup -1/. Observations on KO/sup +/ in the same series of experiments give good estimates for the thermodynamic properties of K/sub 2/O/sub 2/(g). This leads to an improved interpretation of data on the vaporization of KO/sub 0/ /sub 5/-K/sub 2/O/sub 2/ mixtures and solutions. Similarly literature data on the K/sub 2/O/sub 2/-KO/sub 2/ system have been collected and reexamined, leading to the values ..delta..H/sub f,298//sup 0/ = -495.4 kJ mol/sup -1/ and S/sub 298//sup 0/ = 110.1 J mol/sup -1/ K/sup -1/ for K/sub 2/O/sub 2/(s). We have calculated a preliminary phase diagram for the entire region from KO/sub 0/ /sub 5/ to KO/sub 2/, treating the liquid as solutions of O (1) in KO/sub 0/ /sub 5/ (1). Differential thermal analysis data supporting the calculated phase diagram are reported.

  19. International thermodynamic tables of the fluid state propylene (propene)

    CERN Document Server

    Angus, S; De Reuck, K M

    2013-01-01

    International Thermodynamic Tables of the Fluid State - 7 Propylene (Propene) is a compilation of internationally agreed values of the equilibrium thermodynamic properties of propylene. This book is composed of three chapters, and begins with the presentation of experimental result of thermodynamic studies compared with the equations used to generate the tables. The succeeding chapter deals with correlating equations for thermodynamic property determination of propylene. The last chapter provides the tabulations of the propylene's thermodynamic properties and constants. This book will prove

  20. Thermodynamic properties of organic compounds estimation methods, principles and practice

    CERN Document Server

    Janz, George J

    1967-01-01

    Thermodynamic Properties of Organic Compounds: Estimation Methods, Principles and Practice, Revised Edition focuses on the progression of practical methods in computing the thermodynamic characteristics of organic compounds. Divided into two parts with eight chapters, the book concentrates first on the methods of estimation. Topics presented are statistical and combined thermodynamic functions; free energy change and equilibrium conversions; and estimation of thermodynamic properties. The next discussions focus on the thermodynamic properties of simple polyatomic systems by statistical the

  1. On stringy thresholds in SYM/AdS thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Barbon, J.L.F. E-mail: barbon@mail.cem.ch; Kogan, I.I. E-mail: i.kogan@physics.ox.ac.uk; Rabinovici, E. E-mail: eliezer@vxcern.cern.ch

    1999-04-05

    We consider aspects of the role of stringy scales and Hagedorn temperatures in the correspondence between various field theories and AdS-type spaces. The boundary theory is set on a toroidal world-volume to enable small scales to appear in the supergravity backgrounds also for low field-theory temperatures. We find that thermodynamical considerations tend to favour background manifolds with no string-size characteristic scales. The gravitational dynamics censors the reliable exposure of Hagedorn physics on the supergravity side, and the system does not allow the study of the Hagedorn scale by low-temperature field theories. These results are obtained following some heuristic assumptions on the character of stringy modifications to the gravitational backgrounds. A rich phenomenology appears on the supergravity side, with different string backgrounds dominating in different regions, which should have field-theoretic consequences. Six-dimensional world-volumes turn out to be borderline cases from several points of view. For lower-dimensional world-volumes, a fully holographic behaviour is exhibited to order 1/N{sup 2}, and open strings in their presence are found to have a thermodynamic Hagedorn behaviour similar to that of closed strings in flat space.

  2. Thermodynamics of charged dilatonic BTZ black holes in rainbow gravity

    Science.gov (United States)

    Dehghani, M.

    2018-02-01

    In this paper, the charged three-dimensional Einstein's theory coupled to a dilatonic field has been considered in the rainbow gravity. The dilatonic potential has been written as the linear combination of two Liouville-type potentials. Four new classes of charged dilatonic rainbow black hole solutions, as the exact solution to the coupled field equations of the energy dependent space time, have been obtained. Two of them are correspond to the Coulomb's electric field and the others are consequences of a modified Coulomb's law. Total charge and mass as well as the entropy, temperature and electric potential of the new charged black holes have been calculated in the presence of rainbow functions. Although the thermodynamic quantities are affected by the rainbow functions, it has been found that the first law of black hole thermodynamics is still valid for all of the new black hole solutions. At the final stage, making use of the canonical ensemble method and regarding the black hole heat capacity, the thermal stability or phase transition of the new rainbow black hole solutions have been analyzed.

  3. THE IMPACT OF INTERACTIONS, BARS, BULGES, AND ACTIVE GALACTIC NUCLEI ON STAR FORMATION EFFICIENCY IN LOCAL MASSIVE GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Saintonge, Amelie; Fabello, Silvia; Wang Jing; Catinella, Barbara [Max-Planck Institut fuer Astrophysik, D-85741 Garching (Germany); Tacconi, Linda J.; Genzel, Reinhard; Gracia-Carpio, Javier; Wuyts, Stijn [Max-Planck Institut fuer extraterrestrische Physik, D-85741 Garching (Germany); Kramer, Carsten [Instituto Radioastronomia Milimetrica, Av. Divina Pastora 7, Nucleo Central, E-18012 Granada (Spain); Moran, Sean; Heckman, Timothy M. [Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Schiminovich, David [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Schuster, Karl [Institut de Radioastronomie Millimetrique, 300 Rue de la piscine, F-38406 St Martin d' Heres (France)

    2012-10-20

    Using atomic and molecular gas observations from the GASS and COLD GASS surveys and complementary optical/UV data from the Sloan Digital Sky Survey and the Galaxy Evolution Explorer, we investigate the nature of the variations in the molecular gas depletion time observed across the local massive galaxy population. The large and unbiased COLD GASS sample allows us for the first time to statistically assess the relative importance of galaxy interactions, bar instabilities, morphologies, and the presence of active galactic nuclei (AGNs) in regulating star formation efficiency. We find that both the H{sub 2} mass fraction and depletion time vary as a function of the distance of a galaxy from the main sequence traced by star-forming galaxies in the SFR-M {sub *} plane. The longest gas depletion times are found in below-main-sequence bulge-dominated galaxies ({mu}{sub *} >5 Multiplication-Sign 10{sup 8} M {sub Sun} kpc{sup -2}, C > 2.6) that are either gas-poor (M{sub H{sub 2}}/M {sub *} <1.5%) or else on average less efficient by a factor of {approx}2 than disk-dominated galaxies at converting into stars any cold gas they may have. We find no link between the presence of AGNs and these long depletion times. In the regime where galaxies are disk-dominated and gas-rich, the galaxies undergoing mergers or showing signs of morphological disruptions have the shortest molecular gas depletion times, while those hosting strong stellar bars have only marginally higher global star formation efficiencies as compared to matched control samples. Our interpretation is that the molecular gas depletion time variations are caused by changes in the ratio between the gas mass traced by the CO(1-0) observations and the gas mass in high-density star-forming cores (as traced by observations of, e.g., HCN(1-0)). While interactions, mergers, and bar instabilities can locally increase pressure and raise the ratio of efficiently star-forming gas to CO-detected gas (therefore lowering the CO

  4. Quantum theory and statistical thermodynamics principles and worked examples

    CERN Document Server

    Hertel, Peter

    2017-01-01

    This textbook presents a concise yet detailed introduction to quantum physics. Concise, because it condenses the essentials to a few principles. Detailed, because these few principles –  necessarily rather abstract – are illustrated by several telling examples. A fairly complete overview of the conventional quantum mechanics curriculum is the primary focus, but the huge field of statistical thermodynamics is covered as well. The text explains why a few key discoveries shattered the prevailing broadly accepted classical view of physics. First, matter appears to consist of particles which, when propagating, resemble waves. Consequently, some observable properties cannot be measured simultaneously with arbitrary precision. Second, events with single particles are not determined, but are more or less probable. The essence of this is that the observable properties of a physical system are to be represented by non-commuting mathematical objects instead of real numbers.  Chapters on exceptionally simple, but h...

  5. The Thermodynamical Arrow and the Historical Arrow; Are They Equivalent?

    Directory of Open Access Journals (Sweden)

    Martin Tamm

    2017-08-01

    Full Text Available In this paper, the relationship between the thermodynamic and historical arrows of time is studied. In the context of a simple combinatorial model, their definitions are made more precise and in particular strong versions (which are not compatible with time symmetric microscopic laws and weak versions (which can be compatible with time symmetric microscopic laws are given. This is part of a larger project that aims to explain the arrows as consequences of a common time symmetric principle in the set of all possible universes. However, even if we accept that both arrows may have the same origin, this does not imply that they are equivalent, and it is argued that there can be situations where one arrow may be well-defined but the other is not.

  6. On Stringy Thresholds in SYM/AdS Thermodynamics

    CERN Document Server

    Barbón, José L F; Rabinovici, Eliezer

    1999-01-01

    We consider aspects of the role of stringy scales and Hagedorn temperatures in the correspondence between various field theories and AdS-type spaces. The boundary theory is set on a toroidal world-volume to enable small scales to appear in the supergravity backgrounds also for low field-theory temperatures. We find that thermodynamical considerations tend to favour background manifolds with no string-size characteristic scales. The gravitational dynamics censors the reliable exposure of Hagedorn physics on the supergravity side, and the system does not allow the study of the Hagedorn scale by low-temperature field theories. These results are obtained following some heuristic assumptions on the character of stringy modifications to the gravitational backgrounds. A rich phenomenology appears on the supergravity side, with different string backgrounds dominating in different regions, which should have field-theoretic consequences. Six-dimensional world volumes turn out to be borderline cases from several points ...

  7. Thermodynamics of Growth, Non-Equilibrium Thermodynamics of Bacterial Growth : The Phenomenological and the Mosaic Approach

    NARCIS (Netherlands)

    Westerhoff, Hans V.; Lolkema, Juke S.; Otto, Roel; Hellingwerf, K

    1982-01-01

    Microbial growth is analyzed in terms of mosaic and phenomenological non-equilibrium thermodynamics. It turns out that already existing parameters devised to measure bacterial growth, such as YATP, µ, and Qsubstrate, have as thermodynamic equivalents flow ratio, output flow and input flow. With this

  8. Nonequilibrium Thermodynamics in Biological Systems

    Science.gov (United States)

    Aoki, I.

    2005-12-01

    1. Respiration Oxygen-uptake by respiration in organisms decomposes macromolecules such as carbohydrate, protein and lipid and liberates chemical energy of high quality, which is then used to chemical reactions and motions of matter in organisms to support lively order in structure and function in organisms. Finally, this chemical energy becomes heat energy of low quality and is discarded to the outside (dissipation function). Accompanying this heat energy, entropy production which inevitably occurs by irreversibility also is discarded to the outside. Dissipation function and entropy production are estimated from data of respiration. 2. Human body From the observed data of respiration (oxygen absorption), the entropy production in human body can be estimated. Entropy production from 0 to 75 years old human has been obtained, and extrapolated to fertilized egg (beginning of human life) and to 120 years old (maximum period of human life). Entropy production show characteristic behavior in human life span : early rapid increase in short growing phase and later slow decrease in long aging phase. It is proposed that this tendency is ubiquitous and constitutes a Principle of Organization in complex biotic systems. 3. Ecological communities From the data of respiration of eighteen aquatic communities, specific (i.e. per biomass) entropy productions are obtained. They show two phase character with respect to trophic diversity : early increase and later decrease with the increase of trophic diversity. The trophic diversity in these aquatic ecosystems is shown to be positively correlated with the degree of eutrophication, and the degree of eutrophication is an "arrow of time" in the hierarchy of aquatic ecosystems. Hence specific entropy production has the two phase: early increase and later decrease with time. 4. Entropy principle for living systems The Second Law of Thermodynamics has been expressed as follows. 1) In isolated systems, entropy increases with time and

  9. [Rodenticide resistance and consequences].

    Science.gov (United States)

    Esther, A; Endepols, S; Freise, J; Klemann, N; Runge, M; Pelz, H-J

    2014-05-01

    Resistance to anticoagulant rodenticides, such as warfarin was first described in 1958. Polymorphisms in the vitamin K epoxide reductase complex subunit 1 (VKORC1) gene and respective substitutions of amino acids in the VKOR enzyme are the major cause for rodenticide resistance. Resistant Norway rats in Germany are characterized by the Tyr139Cys genotype, which is spread throughout the northwest of the country. Resistant house mice with the VKOR variants Tyr139Cys, Leu128Ser and Arg12Trp/Ala26Ser/Ala48Thr/Arg61Leu (spretus type) are distributed over a number of locations in Germany. Resistance can reduce management attempts with consequences for stored product protection, hygiene and animal health. Anticoagulants of the first generation (warfarin, chlorophacinone, coumatetralyl) as well as bromadiolone and difenacoum are not an option for the control of resistant Norway rats. The same applies for house mice whereby the tolerance to compounds can be different between local incidences. Due to the higher toxicity and tendency to persist, the most potent anticoagulant rodenticides brodifacoum, flocoumafen and difethialone should be applied but only where resistance is known. In other cases less toxic anticoagulants should be preferred for rodent management in order to mitigate environmental risks. Resistance effects of further VKOR polymorphisms and their combinations, the spread of resistant rats and conditions supporting and reducing resistance should be investigated in order to improve resistance management strategies.

  10. Seismic Consequence Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    M. Gross

    2004-10-25

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

  11. The second laws of quantum thermodynamics.

    Science.gov (United States)

    Brandão, Fernando; Horodecki, Michał; Ng, Nelly; Oppenheim, Jonathan; Wehner, Stephanie

    2015-03-17

    The second law of thermodynamics places constraints on state transformations. It applies to systems composed of many particles, however, we are seeing that one can formulate laws of thermodynamics when only a small number of particles are interacting with a heat bath. Is there a second law of thermodynamics in this regime? Here, we find that for processes which are approximately cyclic, the second law for microscopic systems takes on a different form compared to the macroscopic scale, imposing not just one constraint on state transformations, but an entire family of constraints. We find a family of free energies which generalize the traditional one, and show that they can never increase. The ordinary second law relates to one of these, with the remainder imposing additional constraints on thermodynamic transitions. We find three regimes which determine which family of second laws govern state transitions, depending on how cyclic the process is. In one regime one can cause an apparent violation of the usual second law, through a process of embezzling work from a large system which remains arbitrarily close to its original state. These second laws are relevant for small systems, and also apply to individual macroscopic systems interacting via long-range interactions. By making precise the definition of thermal operations, the laws of thermodynamics are unified in this framework, with the first law defining the class of operations, the zeroth law emerging as an equivalence relation between thermal states, and the remaining laws being monotonicity of our generalized free energies.

  12. Thermodynamics Optimizes the Physiology of Life

    Directory of Open Access Journals (Sweden)

    Gladyshev Georgi

    2014-04-01

    Full Text Available Thermodynamics serves as a basis for optimal solutions of the tasks of physiology, which are solved by organisms in the characteristic process of life: evolution, development, homeostasis, and adaptation. It is stated that the quasiequilibrium thermodynamics of quasiclosed complex systems serves as an impetus of evolution, functions, and activities of all levels of biological systems’ organization.This fact predetermines the use of Gibbs’ methods and leads to a hierarchical thermodynamics in all spheres of physiology. The interaction of structurally related levels and sub-levels of biological systems is determined by the thermodynamic principle of substance stability. Thus, life is accompanied by a thermodynamic optimization of physiological functions of biological systems. Living matter, while functioning and evolving, seeks the minimum of specific Gibbs free energy of structure formation at all levels. The spontaneous search of this minimum takes place with participation of not only spontaneous, but also non-spontaneous processes, initiated by the surrounding environment. The hormone optimization of the treatment of various pathologies, presented by Dr. Sergey A. Dzugan et al. demonstrates the effectiveness of their innovative medical approach.

  13. Thermodynamics of Fluids Under Flow Second Edition

    CERN Document Server

    Jou, David; Criado-Sancho, Manuel

    2011-01-01

    This is the second edition of the book “Thermodynamics of Fluids under Flow,” which was published in 2000 and has now been corrected, expanded and updated. This is a companion book to our other title Extended irreversible thermodynamics (D. Jou, J. Casas-Vázquez and G. Lebon, Springer, 4th edition 2010), and of the textbook Understanding non-equilibrium thermodynamics (G. Lebon, D. Jou and J. Casas-Vázquez, Springer, 2008. The present book is more specialized than its counterpart, as it focuses its attention on the non-equilibrium thermodynamics of flowing fluids, incorporating non-trivial thermodynamic contributions of the flow, going beyond local equilibrium theories, i.e., including the effects of internal variables and of external forcing due to the flow. Whereas the book's first edition was much more focused on polymer solutions, with brief glimpses into ideal and real gases, the present edition covers a much wider variety of systems, such as: diluted and concentrated polymer solutions, polymer ble...

  14. Thermodynamic data-base for metal fluorides

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jae Hyung; Lee, Byung Gik; Kang, Young Ho and others

    2001-05-01

    This study is aimed at collecting useful data of thermodynamic properties of various metal fluorides. Many thermodynamic data for metal fluorides are needed for the effective development, but no report of data-base was published. Accordingly, the objective of this report is to rearrange systematically the existing thermodynamic data based on metal fluorides and is to use it as basic data for the development of pyrochemical process. The physicochemical properties of various metal fluorides and metals were collected from literature and such existing data base as HSC code, TAPP code, FACT code, JANAF table, NEA data-base, CRC handbook. As major contents of the thermodynamic data-base, the physicochemical properties such as formation energy, viscosity, density, vapor pressure, etc. were collected. Especially, some phase diagrams of eutectic molten fluorides are plotted and thermodynamic data of liquid metals are also compiled. In the future, the technical report is to be used as basic data for the development of the pyrochemical process which is being carried out as a long-term nuclear R and D project.

  15. Elementary statistical thermodynamics a problems approach

    CERN Document Server

    Smith, Norman O

    1982-01-01

    This book is a sequel to my Chemical Thermodynamics: A Prob­ lems Approach published in 1967, which concerned classical thermodynamics almost exclusively. Most books on statistical thermodynamics now available are written either for the superior general chemistry student or for the specialist. The author has felt the need for a text which would bring the intermediate reader to the point where he could not only appreciate the roots of the subject but also have some facility in calculating thermodynamic quantities. Although statistical thermodynamics comprises an essential part of the college training of a chemist, its treatment in general physical chem­ istry texts is, of necessity, compressed to the point where the less competent student is unable to appreciate or comprehend its logic and beauty, and is reduced to memorizing a series of formulas. It has been my aim to fill this need by writing a logical account of the foundations and applications of the sub­ ject at a level which can be grasped by an under...

  16. [Thermodynamics of the origin of life, evolution and aging].

    Science.gov (United States)

    Gladyshev, G P

    2014-01-01

    Briefly discusses the history of the search of thermodynamic approach to explain the origin of life, evolution and aging of living beings. The origin of life is the result of requirement by the quasi-equilibrium hierarchical thermodynamics, in particular, the supramolecular thermodynamics. The evolution and aging of living beings is accompanied with changes of chemical and supramolecular compositions of living bodies, as well as with changes in the composition and structure of all hierarchies of the living world. The thermodynamic principle of substance stability predicts the existence of a single genetic code in our universe. The thermodynamic theory optimizes physiology and medicine and recommends antiaging diets and medicines. Hierarchical thermodynamics forms the design diversity of culture and art. The thermodynamic theory of origin of life, evolution and aging is the development of Clausius-Gibbs thermodynamics. Hierarchical thermodynamics is the mirror of Darwin-Wallace's-theory.

  17. Consequences of sleep deprivation.

    Science.gov (United States)

    Orzeł-Gryglewska, Jolanta

    2010-01-01

    This paper presents the history of research and the results of recent studies on the effects of sleep deprivation in animals and humans. Humans can bear several days of continuous sleeplessness, experiencing deterioration in wellbeing and effectiveness; however, also a shorter reduction in the sleep time may lead to deteriorated functioning. Sleeplessness accounts for impaired perception, difficulties in keeping concentration, vision disturbances, slower reactions, as well as the appearance of microepisodes of sleep during wakefulness which lead to lower capabilities and efficiency of task performance and to increased number of errors. Sleep deprivation results in poor memorizing, schematic thinking, which yields wrong decisions, and emotional disturbances such as deteriorated interpersonal responses and increased aggressiveness. The symptoms are accompanied by brain tissue hypometabolism, particularly in the thalamus, prefrontal, frontal and occipital cortex and motor speech centres. Sleep deficiency intensifies muscle tonus and coexisting tremor, speech performance becomes monotonous and unclear, and sensitivity to pain is higher. Sleeplessness also relates to the changes in the immune response and the pattern of hormonal secretion, of the growth hormone in particular. The risk of obesity, diabetes and cardiovascular disease increases. The impairment of performance which is caused by 20-25 hours of sleeplessness is comparable to that after ethanol intoxication at the level of 0.10% blood alcohol concentration. The consequences of chronic sleep reduction or a shallow sleep repeated for several days tend to accumulate and resemble the effects of acute sleep deprivation lasting several dozen hours. At work, such effects hinder proper performance of many essential tasks and in extreme situations (machine operation or vehicle driving), sleep loss may be hazardous to the worker and his/her environment.

  18. Graphite Oxidation Thermodynamics/Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Propp, W.A.

    1998-09-01

    The vulnerability of graphite-matrix spent nuclear fuel to oxidation by the ambient atmosphere if the fuel canister is breached was evaluated. Thermochemical and kinetic data over the anticipated range of storage temperatures (200 to 400 C) were used to calculate the times required for a total carbon mass loss of 1 mgcm-2 from a fuel specimen. At 200 C, the time required to produce even this small loss is large, 900,000 yr. However, at 400 C the time required is only 1.9 yr. The rate of oxidation at 200 C is negligible, and the rate even at 400 C is so small as to be of no practical consequence. Therefore, oxidation of the spent nuclear fuel upon a loss of canister integrity is not anticipated to be a concern based upon the results of this study.

  19. Numerical study of the thermodynamics of clinoatacamite

    Science.gov (United States)

    Khatami, Ehsan; Helton, Joel S.; Rigol, Marcos

    2012-02-01

    We study the thermodynamic properties of the clinoatacamite compound, Cu2(OH)3Cl, by considering several approximate models. They include the Heisenberg model on (i) the uniform pyrochlore lattice, (ii) a very anisotropic pyrochlore lattice, and (iii) a kagome lattice weakly coupled to spins that sit on a triangular lattice. We utilize the exact diagonalization of small clusters with periodic boundary conditions and implement a numerical linked-cluster expansion approach for quantum lattice models with reduced symmetries, which allows us to solve model (iii) in the thermodynamic limit. We find a very good agreement between the experimental uniform susceptibility and the numerical results for models (ii) and (iii), which suggests a weak ferromagnetic coupling between the kagome and triangular layers in clinoatacamite. We also study thermodynamic properties in a geometrical transition between a planar pyrochlore lattice and the kagome lattice.

  20. Industrial Requirements for Thermodynamics and Transport Properties

    DEFF Research Database (Denmark)

    Hendriks, Eric; Kontogeorgis, Georgios; Dohrn, Ralf

    2010-01-01

    . The main results are as follows. There is (still) an acute need for accurate, reliable, and thermodynamically consistent experimental data. Quality is more important than quantity. Similarly, there is a great need for reliable predictive, rather than correlative, models covering a wide range...... of compositions, temperatures, and pressures and capable of predicting primary (phase equilibrium) and secondary (enthalpy, heat capacity, etc.) properties. It is clear that the ideal of a single model covering all requirements is not achievable, but there is a consensus that this ideal should still provide...... reactive systems (simultaneous chemical and physical equilibrium). Education in thermodynamics is perceived as key, for the future application of thermodynamics in the industry. A number of suggestions for improvement were made at all three levels (undergraduate, postgraduate, and professional development...

  1. Stochastic Thermodynamics: A Dynamical Systems Approach

    Directory of Open Access Journals (Sweden)

    Tanmay Rajpurohit

    2017-12-01

    Full Text Available In this paper, we develop an energy-based, large-scale dynamical system model driven by Markov diffusion processes to present a unified framework for statistical thermodynamics predicated on a stochastic dynamical systems formalism. Specifically, using a stochastic state space formulation, we develop a nonlinear stochastic compartmental dynamical system model characterized by energy conservation laws that is consistent with statistical thermodynamic principles. In particular, we show that the difference between the average supplied system energy and the average stored system energy for our stochastic thermodynamic model is a martingale with respect to the system filtration. In addition, we show that the average stored system energy is equal to the mean energy that can be extracted from the system and the mean energy that can be delivered to the system in order to transfer it from a zero energy level to an arbitrary nonempty subset in the state space over a finite stopping time.

  2. Relativistic Thermodynamics: A Modern 4-Vector Approach

    Directory of Open Access Journals (Sweden)

    J. Güémez

    2011-01-01

    Full Text Available Using the Minkowski relativistic 4-vector formalism, based on Einstein's equation, and the relativistic thermodynamics asynchronous formulation (Grøn (1973, the isothermal compression of an ideal gas is analyzed, considering an electromagnetic origin for forces applied to it. This treatment is similar to the description previously developed by Van Kampen (van Kampen (1969 and Hamity (Hamity (1969. In this relativistic framework Mechanics and Thermodynamics merge in the first law of relativistic thermodynamics expressed, using 4-vector notation, such as ΔUμ  =  Wμ  +  Qμ, in Lorentz covariant formulation, which, with the covariant formalism for electromagnetic forces, constitutes a complete Lorentz covariant formulation for classical physics.

  3. Maximal temperature in a simple thermodynamical system

    Science.gov (United States)

    Dai, De-Chang; Stojkovic, Dejan

    2016-06-01

    Temperature in a simple thermodynamical system is not limited from above. It is also widely believed that it does not make sense talking about temperatures higher than the Planck temperature in the absence of the full theory of quantum gravity. Here, we demonstrate that there exist a maximal achievable temperature in a system where particles obey the laws of quantum mechanics and classical gravity before we reach the realm of quantum gravity. Namely, if two particles with a given center of mass energy come at the distance shorter than the Schwarzschild diameter apart, according to classical gravity they will form a black hole. It is possible to calculate that a simple thermodynamical system will be dominated by black holes at a critical temperature which is about three times lower than the Planck temperature. That represents the maximal achievable temperature in a simple thermodynamical system.

  4. Thermodynamics principles characterizing physical and chemical processes

    CERN Document Server

    Honig, Jurgen M

    1999-01-01

    This book provides a concise overview of thermodynamics, and is written in a manner which makes the difficult subject matter understandable. Thermodynamics is systematic in its presentation and covers many subjects that are generally not dealt with in competing books such as: Carathéodory''s approach to the Second Law, the general theory of phase transitions, the origin of phase diagrams, the treatment of matter subjected to a variety of external fields, and the subject of irreversible thermodynamics.The book provides a first-principles, postulational, self-contained description of physical and chemical processes. Designed both as a textbook and as a monograph, the book stresses the fundamental principles, the logical development of the subject matter, and the applications in a variety of disciplines. This revised edition is based on teaching experience in the classroom, and incorporates many exercises in varying degrees of sophistication. The stress laid on a didactic, logical presentation, and on the relat...

  5. Fundamental aspects of plasma chemical physics Thermodynamics

    CERN Document Server

    Capitelli, Mario; D'Angola, Antonio

    2012-01-01

    Fundamental Aspects of Plasma Chemical Physics - Thermodynamics develops basic and advanced concepts of plasma thermodynamics from both classical and statistical points of view. After a refreshment of classical thermodynamics applied to the dissociation and ionization regimes, the book invites the reader to discover the role of electronic excitation in affecting the properties of plasmas, a topic often overlooked by the thermal plasma community. Particular attention is devoted to the problem of the divergence of the partition function of atomic species and the state-to-state approach for calculating the partition function of diatomic and polyatomic molecules. The limit of ideal gas approximation is also discussed, by introducing Debye-Huckel and virial corrections. Throughout the book, worked examples are given in order to clarify concepts and mathematical approaches. This book is a first of a series of three books to be published by the authors on fundamental aspects of plasma chemical physics.  The next bo...

  6. The calculation of thermodynamic properties of molecules

    DEFF Research Database (Denmark)

    van Speybroeck, Veronique; Gani, Rafiqul; Meier, Robert Johan

    2010-01-01

    Thermodynamic data are key in the understanding and design of chemical processes. Next to the experimental evaluation of such data, computational methods are valuable and sometimes indispensable tools in obtaining heats of formation and Gibbs free energies. The major toolboxes to obtain such quan......Thermodynamic data are key in the understanding and design of chemical processes. Next to the experimental evaluation of such data, computational methods are valuable and sometimes indispensable tools in obtaining heats of formation and Gibbs free energies. The major toolboxes to obtain...... molecules the combination of group contribution methods with group additive values that are determined with the best available computational ab initio methods seems to be a viable alternative to obtain thermodynamic properties near chemical accuracy. New developments and full use of existing tools may lead...

  7. Teaching Differentials in Thermodynamics using Spatial Visualization

    CERN Document Server

    Wang, Chih-Yueh

    2011-01-01

    The greatest difficulty that is encountered by students in Thermodynamics classes is to find relationships between variables and solve a total differential equation that relates one thermodynamic state variable to two mutually-independent state variables. Rules of differentiation, including the total differential and the cyclic rule, are fundamental to solving thermodynamics problems. However, many students do not well understand such basic mathematics principles, because the underlying geometric meaning is unclear to them. Studies have shown that proficient symbolic techniques may become an obstacle to learning in a qualitative approach. Spatial visualization allows an emergence of new reasoning for students. In this investigation, the total differential rule and the cyclic rule are interpreted geometrically.

  8. Smoothed generalized free energies for thermodynamics

    Science.gov (United States)

    van der Meer, Remco; Ng, Nelly Huei Ying; Wehner, Stephanie

    2017-12-01

    In the study of thermodynamics for nanoscale quantum systems, a family of quantities known as generalized free energies have been derived as necessary and sufficient conditions that govern state transitions. These free energies become important especially in the regime where the system of interest consists of only a few (quantum) particles. In this work, we introduce a family of smoothed generalized free energies, by constructing explicit smoothing procedures that maximize or minimize the free energy over an ɛ ball of quantum states. In contrast to previously known smoothed free energies, these quantities now allow us to make an operational statement for approximate thermodynamic state transitions. We show that these smoothed quantities converge to the standard free energy in the thermodynamic limit.

  9. Gravity and Nonequilibrium Thermodynamics of Classical Matter

    CERN Document Server

    Hu, B L

    2010-01-01

    Renewed interest in deriving gravity (more precisely, the Einstein equations) from thermodynamics considerations [1, 2] is stirred up by a recent proposal that 'gravity is an entropic force' [3] (see also [4]). Even though I find the arguments justifying such a claim in this latest proposal rather ad hoc and simplistic compared to the original one I would unreservedly support the call to explore deeper the relation between gravity and thermodynamics, this having the same spirit as my long-held view that general relativity is the hydrodynamic limit [5, 6] of some underlying theories for the microscopic structure of spacetime - all these proposals, together with that of [7, 8], attest to the emergent nature of gravity [9]. In this first paper of two we set the modest goal of studying the nonequilibrium thermodynamics of classical matter only, bringing afore some interesting prior results, without invoking any quantum considerations such as Bekenstein-Hawking entropy, holography or Unruh effect. This is for the ...

  10. Thermodynamic stability limits of simple monoatomic materials.

    Science.gov (United States)

    Gallington, Leighanne C; Bongiorno, Angelo

    2010-05-07

    This computational study addresses the thermodynamical stability of superheated crystals. Molecular dynamics simulations are employed to derive the caloric curves of the solid and liquid phases of a material. Caloric curves are used to derive thermodynamic state functions, the parameters of the equilibrium melting phase transition, and the regions of thermodynamical stability of the liquid and solid phases. Molecular dynamics trajectories are also analyzed to gain insight on the mechanisms leading to the instability of the homogeneous superheated solid phase. This study shows that in simple and homogeneous solids the configurational entropy is not zero and that its excitations can occur without disrupting the crystallinity of the lattice. The superheating and supercooling limits of the solid and liquid phases are found to correspond to states of equal entropy and enthalpy.

  11. Kinetics and thermodynamics of living copolymerization processes.

    Science.gov (United States)

    Gaspard, Pierre

    2016-11-13

    Theoretical advances are reported on the kinetics and thermodynamics of free and template-directed living copolymerizations. Until recently, the kinetic theory of these processes had only been established in the fully irreversible regime, in which the attachment rates are only considered. However, the entropy production is infinite in this regime and the approach to thermodynamic equilibrium cannot be investigated. For this purpose, the detachment rates should also be included. Inspite of this complication, the kinetics can be exactly solved in the regimes of steady growth and depolymerization. In this way, analytical expressions are obtained for the mean growth velocity, the statistical properties of the copolymer sequences, as well as the thermodynamic entropy production. The results apply to DNA replication, transcription and translation, allowing us to understand important aspects of molecular evolution.This article is part of the themed issue 'Multiscale modelling at the physics-chemistry-biology interface'. © 2016 The Author(s).

  12. Black Hole Thermodynamics and Lorentz Symmetry

    Science.gov (United States)

    Jacobson, Ted; Wall, Aron C.

    2010-08-01

    Recent developments point to a breakdown in the generalized second law of thermodynamics for theories with Lorentz symmetry violation. It appears possible to construct a perpetual motion machine of the second kind in such theories, using a black hole to catalyze the conversion of heat to work. Here we describe and extend the arguments leading to that conclusion. We suggest the inference that local Lorentz symmetry may be an emergent property of the macroscopic world with origins in a microscopic second law of causal horizon thermodynamics.

  13. Consistent thermodynamic properties of lipids systems

    DEFF Research Database (Denmark)

    Cunico, Larissa; Ceriani, Roberta; Sarup, Bent

    Physical and thermodynamic properties of pure components and their mixtures are the basic requirement for process design, simulation, and optimization. In the case of lipids, our previous works[1-3] have indicated a lack of experimental data for pure components and also for their mixtures...... different pressures, with azeotrope behavior observed. Available thermodynamic consistency tests for TPx data were applied before performing parameter regressions for Wilson, NRTL, UNIQUAC and original UNIFAC models. The relevance of enlarging experimental databank of lipids systems data in order to improve...

  14. Horizon thermodynamics from Einstein's equation of state

    Science.gov (United States)

    Hansen, Devin; Kubizňák, David; Mann, Robert B.

    2017-08-01

    By regarding the Einstein equations as equation(s) of state, we demonstrate that a full cohomogeneity horizon first law can be derived in horizon thermodynamics. In this approach both the entropy and the free energy are derived concepts, while the standard (degenerate) horizon first law is recovered by a Legendre projection from the more general one we derive. These results readily generalize to higher curvature gravities where they naturally reproduce a formula for the entropy without introducing Noether charges. Our results thus establish a way of how to formulate consistent black hole thermodynamics without conserved charges.

  15. Nonequilibrium thermodynamics and Nose-Hoover dynamics.

    Science.gov (United States)

    Esposito, Massimiliano; Monnai, Takaaki

    2011-05-12

    We show that systems driven by an external force and described by Nose-Hoover dynamics allow for a consistent nonequilibrium thermodynamics description when the thermostatted variable is initially assumed in a state of canonical equilibrium. By treating the "real" variables as the system and the thermostatted variable as the reservoir, we establish the first and second law of thermodynamics. As for Hamiltonian systems, the entropy production can be expressed as a relative entropy measuring the system-reservoir correlations established during the dynamics.

  16. An open-source thermodynamic software library

    DEFF Research Database (Denmark)

    Ritschel, Tobias Kasper Skovborg; Gaspar, Jozsef; Capolei, Andrea

    This is a technical report which accompanies the article ”An open-source thermodynamic software library” which describes an efficient Matlab and C implementation for evaluation of thermodynamic properties. In this technical report we present the model equations, that are also presented in the paper......, together with a full set of first and second order derivatives with respect to temperature and pressure, and in cases where applicable, also with respect to mole numbers. The library is based on parameters and correlations from the DIPPR database and the Peng-Robinson and the Soave-Redlich-Kwong equations...

  17. Closed power cycles thermodynamic fundamentals and applications

    CERN Document Server

    Invernizzi, Costante Mario

    2013-01-01

    With the growing attention to the exploitation of renewable energies and heat recovery from industrial processes, the traditional steam and gas cycles are showing themselves often inadequate. The inadequacy is due to the great assortment of the required sizes power and of the large kind of heat sources. Closed Power Cycles: Thermodynamic Fundamentals and Applications offers an organized discussion about the strong interaction between working fluids, the thermodynamic behavior of the cycle using them and the technological design aspects of the machines. A precise treatment of thermal engines op

  18. Qualitative and quantitative reasoning about thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Skorstad, G.; Forbus, K.

    1989-11-01

    One goal of qualitative physics is to capture the tacit knowledge of engineers and scientists. It is shown how Qualitative Process theory can be used to express concepts of engineering thermodynamics. In particular, it is shown how to integrate qualitative and quantitative knowledge to solve textbook problems involving thermodynamic cycles, such as gas turbine plants and steam power plants. These ideas were implemented in a program called SCHISM. Its analysis of a sample textbook problem is described and plans for future work are discussed.

  19. Numerical Simulation of Cyclic Thermodynamic Processes

    DEFF Research Database (Denmark)

    Andersen, Stig Kildegård

    2006-01-01

    This thesis is on numerical simulation of cyclic thermodynamic processes. A modelling approach and a method for finding periodic steady state solutions are described. Examples of applications are given in the form of four research papers. Stirling machines and pulse tube coolers are introduced......, compressible flow in one space dimension is presented. The implementation produces models where all the equations, which are on a form that should be understandable to someone with a background in engineering thermodynamics, can be accessed and modified individually. The implementation was designed to make...

  20. Thermodynamic significance of human basal metabolism

    Science.gov (United States)

    Wang, Cuncheng

    1993-06-01

    The human basal state, a non-equilibrium steady state, is analysed in this paper in the light of the First and Second Laws of Thermodynamics whereby the thermodynamic significance of the basal metabolic rate and its distinction to the dissipation function and exergy loss are identified. The analysis demonstrates the correct expression of the effects of the blood flow on the heat balance in a human-body bio-heat model and the relationship between the basal metabolic rate and the blood perfusion.