[en] 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 detailed study of various thermodynamic cycles. In the meantime, we derive some useful relations.

[en] The ionic fragmentation following B 1s and C 1s excitation of three isomeric carborane cage compounds [closo-dicarbadodecaboranes: orthocarborane (1,2-C2B10H12), metacarborane (1,7-C2B10H12), and paracarborane (1,12-C2B10H12)], is compared with the energetics of decomposition. The fragmentation yields for all three molecules are quite similar. Thermodynamic cycles are constructed for neutral and ionic species in an attempt to systemically characterize single ion closo-carborane creation and fragmentation processes. Lower energy decomposition processes are favored. Among the ionic species, the photon induced decomposition is dominated by BH+ and BH2+ fragment loss. Changes in ion yield associated with core to bound excitations are observed

[en] The pamphlet in hand which has been published by the 'Informationszentrale der Elektrizitaetswirtschaft e.V. (IZE), is an explanation of the second law of thermodynamics. (DG)

[en] Is suggested the method of gas cycle calculation for the mixture N₂O₄-NO with the ''frozen'' expansion process in the turbine. The method is cited for two variations of gas composition, frozen and equilibrium, on the regenerator inlet upon the hot side

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[en] Theoretical thermal efficiencies and theoretical effectivenesses of six kinds of basic gas cycles, including the Carnot, Otto, Diesel, Takemura, Atkinson and Joule cycles, were compared with one another under the restriction of constant heat-addition. Relations between the available work content of heat added and the exergy change in several thermodynamic processes were also examined. It is concluded that the Atkinson cycle has the highest thermal efficiency and the second best effectiveness among the gas cycles examined. The exergy changes in an isochoric heating-process in closed systems and in an isobaric heating-process in open systems agree with the available work contents of heat added in these processes. Thus, the exergy increment in a heating process should not be generally adopted as the denominator for the theoretical effectiveness

[en] Feedback can be utilized to convert information into useful work, making it an effective tool for increasing the performance of thermodynamic engines. Using feedback reversibility as a guiding principle, we devise a method for designing optimal feedback protocols for thermodynamic engines that extracts all the information gained during feedback as work. Our method is based on the observation that in a feedback-reversible process the measurement and the time-reversal of the ensuing protocol both prepare the system in the same probabilistic state. We illustrate the utility of our method with two examples of the multi-particle Szilard engine. (paper)

[en] The implications of the High Efficiency Power Cycle for fusion reactors are examined. The proposed cycle converts most all of the high grade CTR heat input to electricity. A low grade thermal input (T approximately 100⁰C) is also required, and this can be supplied at low cost geothermal energy at many locations in the U. S. Approximately 3 KW of low grade heat is required per KW of electrical output. The thermodynamics and process features of the proposed cycle are discussed. Its advantages for CTR's are that low Q machines (e.g. driven Tokamaks, mirrors) can operate with a high (approximately 80 percent) conversion of CTR fusion energy to electricity, where with conventional power cycles no plant output could be achieved with such low Q operation

[en] Comprehensive design studies and assessments were carried out in the 1970s on an advanced, direct-cycle high-temperature gas-cooled reactor (HTGR) option. These led to conclusions in 1980 that an extensive development effort was necessary to establish a technically viable gas turbine HTGR (HTGR-GT) plant to satisfy demanding safety and licensing criteria and that further design innovation was necessary to identify plant features for improved economics. Accordingly, the steam cycle HTGR was designated as the lead plant and the HTGR-GT classed as a long-term, advanced technology, second-generation HTGR plant option. With the necessary development, a dry-cooled gas turbine plant with a reactor outlet temperature of approximately 950⁰C, operating in a combined cycle mode (with an efficiency of over 50%) or cogeneration mode (power plus process steam production), could be realized in the early decades of the 21st century. This paper reviews the status of the Brayton cycle plant and gives a perspective on the HTGR-GT plant as a follow-on option to the steam Rankine cycle lead plant