Thermodynamics energy sources

Russell and Hall (this volume) adopt this premise and suggest that life first emerged where dissolved H2 from submarine hot springs redueed dissolved CO2 in the ancient ocean. They propose that iron-nickel sulfide minerals served as catalysts in the generation of essential biomolecules. Other important thermodynamic energy sources, Russell and Hall note, resulted from the strong pH and thermal gradients between the acidic ocean and alkaline hydrothermal fluids. 

Autocatalysis can cause sustained oscillations in batch systems. This idea originally met with skepticism. Some chemists believed that sustained oscillations would violate the second law of thermodynamics, but this is not true. Oscillating batch systems certainly exist, although they must have some external energy source or else the oscillations will eventually subside. An important example of an oscillating system is the circadian rhythm in animals. A simple model of a chemical oscillator, called the Lotka-Volterra reaction, has the assumed mechanism ... 

The local conditions of temperature and pressure, as well as the new energy source in the form of the electrochemical gradient, can all be incorporated into the Gibbs free energy by adding new terms to the chemical potential. Variation of AG and AH with temperature are all standard thermodynamics, although we will resist the temptation to explore them here. 

The very expression energy source is actually a misnomer. As is known since the early days of thermodynamics, and formulated as the first law, energy is conserved in any physical process. Since energy cannot be created or destroyed, nothing can be an energy source, or sink. Devices we call energy sources do not create energy, they convert it from a form not suitable for our needs to a form that is suitable, a form we can do work with. 

For the phosphotransferase system there is no problem in identifying the energy source for the establishment of the thermodynamic potential gradient. It is apparent that a high-energy phosphate bond in phospho-enol-pyruvate is the immediate source of the energy responsible for the vectorial translocation of the sugar molecule across the membrane (17). 

Our earth is limited but not closed. Nearly 100% energy source of living creatures depends on photosynthesis, including the fossil fuels that are the main energy resource of human life. This is the important point for our future that our earth is open to the universe, more correctly to the sun. If the earth is closed no animals and plants can exist. The first law of thermodynamics designates that the... 

These thermodynamic efficiencies may be considered to be on the low side, particularly for land plants. But then it must be noted that this photosynthesis is an activity of a living system for which photosynthesis, or rather the capture of solar energy and its transformation into chemical energy, is only one aspect of life. Supply may exceed demand. Therefore, it may well be that if the only purpose of photosynthesis is the capture of light as an energy source, the efficiencies would have been higher. Support for this conjecture can be found in a calculation by Lehninger [12], who shows that under certain laboratory... 

This book answers this question for industrial processes, in particular those in the energy and chemical industry. Having a long experience in joint efforts with industry and with teaching, the authors use the fundamental laws of thermodynamics as a point of departure. They contrast the present industrial society with the emerging metabolic society, in which mass production and consumption are in harmony with the natural environment through closure of material cycles. These are ultimately driven by the primary new energy source, the sun. This book provides keys to a quantification of process efficiency and sustainability. This is illustrated in case studies, examples, and problems. 

A new energy system in which carbon is reused cyclically was discussed. A carbon recycle system has already existed in nature as a natural carbon neutral system. In this paper, a concept of an Active Carbon Neutral Energy System (ACRES) was proposed against the natural system. C02 is regenerated artificially into hydrocarbons consuming a primary energy source with no C02 emission, and re-used cyclically in ACRES. ACRES recycles carbon, and transform energy without C02 emission. Because ACRES was expected to solve the above carbon problems, the feasibility of ACRES was discussed thermodynamically. 

From thermodynamic considerations the maximum energy that can be derived from a specified mass of reactants can be calculated. This calculation is of particular interest in the design of portable energy sources. The theoretical specific energy is the ratio of Gibbs free energy of the reaction to the mass of the reactants ... 

Note that the hydrolysis of two high-energy phosphate bonds in ATP provides the energy source for the reaction. The inorganic pyrophosphate, PPi, is subsequently broken down to two phosphate ions by inorganic pyrophosphatase. The action of this enzyme means that very little PPi remains in the cell, making the synthesis of the fatty acyl-CoA favored. This is an example of metabolic coupling, the process whereby a thermodynamically unfavored reaction is allowed because it shares an intermediate (in this case PPO with a favored one. 

Cozzl, C. "Thermodynamics and Energy Accountancy in Industrial Processes." Energy Sources, 2, No. 2, 165 (1975). 

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