Biofuels from micro-organisms: Thermodynamic analysis of sustainability

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How Life Works — A Continuous Seebeck-Peltier Transition in Cell Membrane?

2noThis paper develops a non-equilibrium thermodynamic approach to life, with particular regards to the membrane role. The Onsager phenomenological coefficients are introduced in order to point out the thermophysical properties of the cell systems. The fundamental role of the cell membrane electric potential is highlighted, in relation to ions and heat fluxes, pointing out the strictly relation between heat exchange and the membrane electric potential. A Seebeck-like and Peltier-like effects emerge in order to simplify the description of the heat and the ions fluxes. Life is described as a continuos transition between the Peltier-like effect to the Seebeck-like one, and viceversa.openopenLucia, U.; Grisolia, G.Lucia, U.; Grisolia, G

Exergy Inefficiency: An Indicator for Sustainable Development Analysis

The present days can be considered a crossroad in the history of our world because the economic, social, and environmental needs do not agree one another. The result is the present socio-economic difficulties, from which it seems very difficult to escape. A new viewpoint must be introduced, but it cannot be based on the usual economic indicators. So, a new viewpoint and a new related approach are required. In this paper we suggest three new indicators based on an engineering approach of irreversibility. They allow us to evaluate both the technological level and the environmental impact of the production processes and the socio-economic conditions of the countries. Indeed, they are based on the exergy analysis and on the irreversible thermodynamic approach, in order to evaluate the inefficiency both of the process and of the production systems, and the related consequences. Three applications are summarized in order to highlight the possible interest from different scientists and researchers in engineering, economy, etc, in order to develop sustainable approaches and policies for decision makers. Keywords: Bioeconomics, Entropy, Exergy, Irreversibility, Sustainability, Thermoeconomic

Time & Clocks: A thermodynamic approach

Abstract Recently, the definition of time has been introduced by introducing the irreversible thermodynamics into the analysis of the atomic irreversibility. In this way, time is defined by means of the entropy generation and the entropy rate. But, which clock can be used to measure this time? In this paper a thermodynamic clock is designed by using the properties of a black body. So, a relation between the definition of time by entropy and a measure of temperature of a black body has been obtained. The result obtained agree with the Relativity and the thermal time hypothesis, obtaining a link between quantum mechanics, relativity and thermodynamics, by the irreversible thermodynamic clock operational approach

Time: a Constructal viewpoint & its consequences

In the environment, there exists a continuous interaction between electromagnetic radiation and matter. So, atoms continuously interact with the photons of the environmental electromagnetic fields. This electromagnetic interaction is the consequence of the continuous and universal thermal nonequilibrium, that introduces an element of randomness to atomic and molecular motion. Consequently, a decreasing of path probability required for microscopic reversibility of evolution occurs. Recently, an energy footprint has been theoretically proven in the atomic electron-photon interaction, related to the well known spectroscopic phase shift effect, and the results on the irreversibility of the electromagnetic interaction with atoms and molecules, experimentally obtained in the late sixties. Here, we want to show how this quantum footprint is the “origin of time”. Last, the result obtained represents also a response to the question introduced by Einstein on the analysis of the interaction between radiation and molecules when thermal radiation is considered; he highlighted that in general one restricts oneself to a discussion of the energy exchange, without taking the momentum exchange into account. Our result has been obtained just introducing the momentum into the quantum analysis

Biofuels from abandoned mines: A starting point for future developments

Abandoned mines and quarries represent sites with the request of restoration due to their pollution. On the other hand, biofuels represent a response to the present request of sustainable energy, in order to reduce the CO2 emission, in transportation, but also in energy production and domestic use. However, biofuels production seldom requires lands for the biomass cultivation. In this paper, the use of the dismissed mines and quarries is suggested for the cultivation of algae, as biomass production. To support this approach, a theoretical numerical evaluation of a typical dismissed quarry is developed in order to highlight the feasibility of the approach itself

A non-equilibrium thermodynamic approach to symmetry breaking in cancer

This paper develops a non-equilibrium thermodynamics approach to oncogenesis, with a particular focus on ‘symmetry breaking’. The Onsager phenomenological coefficients are introduced to show the biophysical and thermophysical properties of cellular systems with differences between normal and cancerous cells. Seebeck- and Peltier-like effects are introduced to simplify the description of heat exchange and ion fluxes, in an effort to characterize the distinct role of the cellular electric membrane potential. Our results indicate that oncogenesis leads to changes in: (i) the thermophysical properties of the cell cytoplasm, caused by differences in density and heat capacity, (ii) the interactions with the micro-environment, (iii) geometrical characteristics, both in fractal dimensions and in shape symmetry, and (iv) the constitutive properties of membrane fluxes. This presents a unifying biophysics concept for such diverse characteristics, and it may yield new diagnostic and therapeutic opportunities

Constructal law analysis of Cl− transport in eyes aqueous humor

Progressive loss-of-vision related to any intraocular disorder is known as glaucoma. Secretion of aqueous humor is physiologically important to provide nutrients and oxygen to the avascular anterior segment and ensuring normal visual function, even if, nowadays reducing the secretory rate to lower intraocular pressure is a major strategy in treating glaucomatous patients. Understanding the mechanisms and regulation of aqueous humor formation is very important to develop possible new approaches to lower intraocular pressure,but today there isn’t any comprehensive model of the regulation of these component in forming aqueous humor. In this paper Construcal law is used to suggest how the Cl− fluxes can determine the water inflow and outflow, and, consequently, how the intraocular pressure is controlled by these fluxes