scholarly journals Heat flowing from cold to hot without external intervention by using a “thermal inductor”

2019 ◽  
Vol 5 (4) ◽  
pp. eaat9953 ◽  
Author(s):  
A. Schilling ◽  
X. Zhang ◽  
O. Bossen
Keyword(s):  
Ambient Temperature ◽  
Second Law Of Thermodynamics ◽  
Thermal Bath ◽  
Quasi Equilibrium ◽  
External Energy ◽  
Peltier Element ◽  
Pass Through ◽  
External Intervention ◽  
Two Bodies ◽  
External Driving

The cooling of boiling water all the way down to freezing, by thermally connecting it to a thermal bath held at ambient temperature without external intervention, would be quite unexpected. We describe the equivalent of a “thermal inductor,” composed of a Peltier element and an electric inductance, which can drive the temperature difference between two bodies to change sign by imposing inertia on the heat flowing between them, and enable continuing heat transfer from the chilling body to its warmer counterpart without the need of an external driving force. We demonstrate its operation in an experiment and show that the process can pass through a series of quasi-equilibrium states while fully complying with the second law of thermodynamics. This thermal inductor extends the analogy between electrical and thermal circuits and could serve, with further progress in thermoelectric materials, to cool hot materials well below ambient temperature without external energy supplies or moving parts.

Why did life emerge?

2008 ◽  
Vol 7 (3-4) ◽  
pp. 293-300 ◽  
Author(s):  
Arto Annila ◽  
Erkki Annila
Keyword(s):  
Driving Force ◽  
Second Law Of Thermodynamics ◽  
Equation Of Motion ◽  
Energy Transduction ◽  
External Energy ◽  
Demarcation Line ◽  
Theory Of Evolution ◽  
Transduction Mechanisms ◽  
Fitness Criterion ◽  
Evolution By Natural Selection

AbstractMany mechanisms, functions and structures of life have been unraveled. However, the fundamental driving force that propelled chemical evolution and led to life has remained obscure. The second law of thermodynamics, written as an equation of motion, reveals that elemental abiotic matter evolves from the equilibrium via chemical reactions that couple to external energy towards complex biotic non-equilibrium systems. Each time a new mechanism of energy transduction emerges, e.g., by random variation in syntheses, evolution prompts by punctuation and settles to a stasis when the accessed free energy has been consumed. The evolutionary course towards an increasingly larger energy transduction system accumulates a diversity of energy transduction mechanisms, i.e. species. The rate of entropy increase is identified as the fitness criterion among the diverse mechanisms, which places the theory of evolution by natural selection on the fundamental thermodynamic principle with no demarcation line between inanimate and animate.

STUDY OF THE CROSSOVER FROM NON-EQUILIBRIUM STATIONARY STATES TO QUASI-EQUILIBRIUM STATES IN A DRIVEN DIFFUSIVE SYSTEM UNDER THE INFLUENCE OF AN OSCILLATORY FIELD

2002 ◽  
Vol 16 (27) ◽  
pp. 4165-4174 ◽  
Author(s):  
ROBERTO A. MONETTI ◽  
EZEQUIEL V. ALBANO
Keyword(s):  
Steady State ◽  
Lattice Gas ◽  
Thermal Bath ◽  
Quasi Equilibrium ◽  
Stationary States ◽  
Driving Field ◽  
Driven Diffusive System ◽  
Crossover Behavior ◽  
Diffusive System ◽  
Non Equilibrium

A driven diffusive system (DDS) is a lattice-gas in contact with a thermal bath in the presence of an external field. Such DDS constantly gains (losses) energy from (to) the driving field (thermal bath) and therefore, for long enough time, it reaches a non-equilibrium steady-state (NESS) with a generally unknown statistical distribution. It is found that if the constant driving is replaced by an oscillatory field of magnitude E and period τ, the system exhibits a crossover from NESS to a quasi-equilibrium state (QES) driven by τ. The crossover behavior is characterized by a typical crossover time which is proportional to the lattice side and consequently relevant to confined systems.

scholarly journals Effect of Elevated Temperature on Residual Strength of Self Compacted Concrete

2020 ◽  
Vol 11 (2) ◽  
pp. 107-115
Author(s):  
Snahashish Paul ◽  
Muhammad Harunur Rashid ◽  
Md Anisur Rahman
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Ambient Temperature ◽  
Construction Industry ◽  
Modulus Of Elasticity ◽  
Elevated Temperatures ◽  
Water Quenching ◽  
Air Cooling ◽  
External Energy ◽  
Residual Capacity

Self Compacted Concrete (SCC) is a material used in the construction industry to ensure proper compaction of concrete without providing any external energy. In case of exposure of SCC to accidental fire, an assessment of its residual capacity is needed. This study covers the observation of residual compressive strength, tensile strength and modulus of elasticity of self compacted concrete under elevated temperatures (150, 300, 450, 600 and 800⁰C) and cooling conditions (air cooling and water quenching). The compressive strength increased at 150⁰C and decreased continuously after this temperature. However, tensile strength and modulus of elasticity decreased at elevated temperatures compared with ambient temperature. The compressive strength at ambient temperature (30⁰C) was 27.0 MPa, and it raised to 28.7 MPa at 150⁰C for air cooling and 27.8 MPa for water quenching. Journal of Engineering Science 11(2), 2020, 107-115

scholarly journals The fourth law of thermodynamics: steepest entropy ascent

2020 ◽  
Vol 378 (2170) ◽  
pp. 20190168 ◽  
Author(s):  
Gian Paolo Beretta
Keyword(s):  
Laws Of Nature ◽  
Second Law Of Thermodynamics ◽  
Physical Reality ◽  
The Body ◽  
Quasi Equilibrium ◽  
Natural Phenomena ◽  
Onsager Reciprocity ◽  
Fluctuation Dissipation ◽  
Effective Models ◽  
Non Equilibrium

When thermodynamics is understood as the science (or art) of constructing effective models of natural phenomena by choosing a minimal level of description capable of capturing the essential features of the physical reality of interest, the scientific community has identified a set of general rules that the model must incorporate if it aspires to be consistent with the body of known experimental evidence. Some of these rules are believed to be so general that we think of them as laws of Nature, such as the great conservation principles, whose ‘greatness’ derives from their generality, as masterfully explained by Feynman in one of his legendary lectures. The second law of thermodynamics is universally contemplated among the great laws of Nature. In this paper, we show that in the past four decades, an enormous body of scientific research devoted to modelling the essential features of non-equilibrium natural phenomena has converged from many different directions and frameworks towards the general recognition (albeit still expressed in different but equivalent forms and language) that another rule is also indispensable and reveals another great law of Nature that we propose to call the ‘fourth law of thermodynamics’. We state it as follows: every non-equilibrium state of a system or local subsystem for which entropy is well defined must be equipped with a metric in state space with respect to which the irreversible component of its time evolution is in the direction of steepest entropy ascent compatible with the conservation constraints. To illustrate the power of the fourth law, we derive (nonlinear) extensions of Onsager reciprocity and fluctuation–dissipation relations to the far-non-equilibrium realm within the framework of the rate-controlled constrained-equilibrium approximation (also known as the quasi-equilibrium approximation). This article is part of the theme issue ‘Fundamental aspects of nonequilibrium thermodynamics’.

The Second Law of Thermodynamics

1993 ◽  
Author(s):  
Greg M. Anderson ◽  
David A. Crerar
Keyword(s):  
Kinetic Energy ◽  
Second Law Of Thermodynamics ◽  
Single Step ◽  
Carnot Cycle ◽  
External Energy ◽  
Energy Transfers ◽  
Deformation Work ◽  
History Of ◽  
External Energy Source ◽  
Definition Of

We have seen that the first great principle of energy transfers is that energy is conserved. The essence of the second principle or law has to do with energy availability, or with the "directionality" of these transfers (processes). In other words, it is observed that once the constraints on the beginning and ending states are decided upon, processes can only proceed spontaneously in one direction between these states and are never observed to proceed in the other direction unless they are "pushed" with an external energy source. For example, a brick can fall off a table onto the floor. The potential energy it has on the table is converted to kinetic energy and then to a certain amount of heat and mechanical deformation (work) upon impact. According to the first law, the energy expended on impact will exactly equal the energy the brick had on the table. Bricks have never been observed to spontaneously cool themselves, convert this heat energy into kinetic energy, and fly from the floor to the table. Such events could exactly satisfy the first law, which clearly has nothing to say about why they don't happen—just that if they did happen, energy would be conserved. It would obviously be very useful to have a method of predicting which way a given process would go under given conditions. It would open the way towards systematizing chemical and mineral reactions, for one thing. We could start to predict which minerals would form under given metamorphic conditions, for example, and perhaps even predict their compositions, because all such changes are simply processes that can be considered to go from one equilibrium state to another. Possibly the greatest single step forward in the history of the development of thermodynamics was the recognition and definition of a parameter, the entropy, which enables such predictions and systematizations to be made. deduced on the basis of years of experience, and then show through use of the Carnot cycle the logical consequences (such as the existence of the entropy and an absolute scale of temperature).

scholarly journals Physiological Sexual Body, Emotional Body and Sexuality

2016 ◽  
Vol 9 (1) ◽  
pp. 41-41
Author(s):  
T. Strepetova ◽  
◽  
D. Trotta ◽  
L. Otranto ◽  
F. Gorga ◽  
...  
Keyword(s):  
External World ◽  
Clinical Applications ◽  
Complex Interaction ◽  
The Body ◽  
The Other ◽  
Sexual Distress ◽  
Pass Through ◽  
The Individual ◽  
Two Bodies ◽  
Sexual Body

Objective: Our body is at the same time a biological and a sexological body. Biological body is innate and based on our genes and their capacity to express and realize their potentials. Our sexual body is acquisite and is related to our education and learning and our capacity to decode and read the external world. Our sexological body is a lot more than our biological body. Our aim is to differentiate the two bodies and the better understand and handle sexual misunderstanding and sexual difficulties. Design and Method: Sexuality as acted and performed is the resulting and final step of a complex interaction of different forces. By means of the observation of the physical and sexual body and its position in the space, its rhythms and its tonicity it is possible to relate to the emotions that live inside and pass through the human being. And, on the contrary, acting on the body, modifying its posture and its movements is possible to influence sexual sensations and feelings. Results: Observing and acting on the physical body is useful in influencing and positively modifying the individual sexual emotional and psychological mind, and to lessen sexual distress or to resolve sexual impairment. Conclusions: Biological and emotional body are tightly related. The observation and the analysis of one body reflect the other as well as the intervention on one of the two bodies can influence and transform the other one. This can lead to important results and clinical applications.

scholarly journals Application of Second-Law Analysis for the Environmental Control Unit at High Ambient Temperature

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3274
Author(s):  
Ammar M. Bahman ◽  
Eckhard A. Groll
Keyword(s):  
Ambient Temperature ◽  
Environmental Control ◽  
Control Unit ◽  
Second Law Of Thermodynamics ◽  
High Ambient Temperature ◽  
Second Law ◽  
Potential Contribution ◽  
Exergy Destruction ◽  
Ambient Conditions ◽  
Second Law Analysis

This paper assesses the application of the second-law of thermodynamics in a military Environmental Control Unit (ECU) to evaluate the exergy destruction (or irreversibility) in each component when operating at high ambient temperature. Experimental testings were conducted on three ECUs, 1.5 (5.3 kW), 3 (10.6 kW), and 5 (17.6 kW) tons of refrigeration (RT), to assess the potential contribution of each component to enhance the overall energy efficiency of the system, and to determine the feasibility of the thermodynamic model presented herein. The analysis provided for extreme high ambient conditions up to 51.7 °C (125 °F). The results yielded that the highest irreversibility was associated with compressors (32.4% to 42.5%). This is followed by the heat exchanges (19.6% to 32.9%) in the case of 1.5-RT and 3-RT units, whereas for the 5-RT unit, the highest irreversibility was associated with the evaporator followed by the one of the compressors. In the 3-RT ECU, the condenser’s second-law efficiency enhanced due to an additional fan, yet the working refrigerant increased the irreversibility in the expansion device. The second-law analysis recognized the components with the highest exergy destruction and identified the direction to enhance the exergetic efficiency of any ECU operating at high-temperature climate.

scholarly journals A hierarchical thermodynamic imperative drives the evolution of self-replicative life systems towards increased complexity

2021 ◽  
Author(s):  
Sergio Menendez
Keyword(s):  
Open Systems ◽  
Energy Levels ◽  
Point Of View ◽  
Coarse Grained ◽  
State Transitions ◽  
Time And Space ◽  
External Energy ◽  
Empirical Observation ◽  
Far From Equilibrium ◽  
External Driving

From a basic thermodynamic point of view life structures can be viewed as dissipative open systems capable of self replication. Energy flowing from the external environment into the system allows growth of its self replicative entities with a concomitant decrease in internal entropy (complexity) and an increase of the overall entropy in the universe, thus observing the second law of thermodynamics. However, efforts to derive general thermodynamic models of life systems have been hampered by the lack of precise equations for far from equilibrium systems subjected to arbitrarily time varying external driving fields (the external energy input), as these systems operate in a non-linear response regime that is difficult to model using classical thermodynamics. Recent theoretical advances, applying time reversal symmetry and coarse grained state transitions, have provided helpful semi-quantitative insights into the thermodynamic constraints that bind the behaviour of far from equilibrium life systems. Setting some additional fundamental constraints based on empirical observations allows us to apply this theoretical framework to gain a further semi-quantitative insight on the thermodynamic boundaries and evolution of self replicative life systems. This analysis suggests that complex self replicative life systems follow a thermodynamic hierarchical organisation based on increasing accessible levels of usable energy (work), which in turn drive an exponential punctuated growth of the system's complexity, stored as internal energy and internal entropy. This growth has historically not been limited by the total energy available from the external driving field for the earth life system, but by the internal system's adaptability needed to access higher levels of usable energy. Therefore, in the absence of external perturbations, the emergence of an initial self replicative dissipative structure capable of variation that enables access to higher energy levels is sufficient to drive the system's growth perpetually towards increased complexity across time and space. Furthermore, the self-replicative system would adopt a hierarchical organisation with all permitted energy niches evolving to be optimally occupied in order to dissipate the work input from the external drive and further adapting as higher energy levels are accessed. This model is consistent with current empirical observation of life systems across both time and space and explains from a thermodynamic point of view the evolutionary patterns of complex life systems on earth. We propose that predictions from this model can be further corroborated in a variety of artificially closed systems and that they are supported by experimental observations of complex ecological systems across the thermodynamic hierarchy.

Organization and Development of the Macronuclear Anlage in Stylonychia Notophora Stokes

1970 ◽  
Vol 6 (2) ◽  
pp. 351-363
Author(s):  
G. R. SAPRA ◽  
C. M. S. DASS
Keyword(s):  
Early Stages ◽  
Break Up ◽  
Pass Through ◽  
Replication Bands ◽  
Two Bodies ◽  
Heavy Labelling

The development of the macronuclear Anlage of Stylonychia notophora was studied by means of cytochemical and autoradiographic techniques. In early stages of its differentiation, the Anlage has its chromatin distributed homogeneously. Nine to ten hours later chromosomes are noticed; the nucleus is possibly diploid. Following this, the number of chromosomes increases progressively resulting in polyploidy. Later, chromosomes uncoil and polytenization follows. After consolidation and shrinkage of these chromosomes, the Anlage splits into two bodies. Five series of replication bands quickly pass through each and the vegetative macronucleus results. Synthesis of RNA by the new macronucleus starts soon after the shrinkage stage. The old macronuclei break up into small spherical bodies which are gradually resorbed in the cytoplasm. When [3H]thymidine is provided continuously to the exconjugants, there is little uptake into the Anlage until the old macronucleus is completely resorbed. Only after this, heavy labelling is noticed. Fate of the previously labelled macronuclei during conjugation shows that their breakdown products are re-utilized for the development of the new macronucleus.

Rotor Vibration Due to Collision With Annular Guard During Passage Through Critical Speed

1998 ◽  
Vol 120 (2) ◽  
pp. 544-550 ◽  
Author(s):  
S. Yanabe ◽  
S. Kaneko ◽  
Y. Kanemitsu ◽  
N. Tomi ◽  
K. Sugiyama
Keyword(s):  
Contact Force ◽  
Critical Speed ◽  
Angular Acceleration ◽  
Runge Kutta Method ◽  
Nonstationary Vibration ◽  
Backward Whirl ◽  
Before And After ◽  
Conservation Of Momentum ◽  
Pass Through ◽  
Two Bodies

This paper deals with a nonstationary vibration of a rotor due to its collision with a guard during passage through a critical speed. An unbalanced rigid rotor supported by springs and dampers is accelerated at a constant angular acceleration and collides with an annular guard supported by springs and dampers. This dynamic process is calculated by the Runge-Kutta method, and effects of system-parameters on the process are discussed. The collision phenomenon is analyzed through two different theories. In the collision theory, the law of conservation of momentum and the coefficient of restitution are used in order to obtain rotor and guard velocities after collision. The impulse of the force induced by collision is assumed to be equal to the momentum change before and after collision. In the contact force theory, the contact force is assumed to be proportional to the overlapped displacement of the two bodies. Few differences are observed between the calculated responses based on the two theories. In some cases, the rotor executes a diverging backward whirl due to the friction force that occurs during collision with the guard and can not pass through the critical speed. The criteria maps for nonoccurrence of the backward whirl are shown.

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