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Entoloma is a relatively large genus in Agaricales, with a rich diversity of species and a wide distribution. In this study, seven new species of Entoloma belonging to the subgenus Cubospora have been identified based on morphological and phylogenetic evidence from subtropical regions of China. Morphologically, E. excavatum is characterized by the yellow, depressed, estriate pileus and medium-sized basidiospores; E. lacticolor is recognized by the white and papillate pileus, adnexed lamellae, and presence of clamp connections; E. phlebophyllum is identified by the pink-to-maroon and estriate pileus, and lamellae with lateral veins; E. rufomarginatum differs from other cuboid-spored species by the lamellae edge which is red-brown-underlined; E. subcycneum is characterized by the white pileus and carneogriseum-type cheilocystidia; E. submurrayi is recognized by the pileus margin exceeding the lamellae, 2-layered pileipellis with hyphae of different widths, and the presence of clamp connections; E. tomentosum is identified by the tomentose pileus, heterogeneous lamella edge, and versiform cheilocystidia with brown-yellow contents. Their distinct taxonomic status is confirmed by the positions of the seven new species in both the ITS + LSU and 3-locus (LSU, tef-1α, rpb2) phylogenetic trees. Detailed descriptions, color photos, and a key to related species are presented. [ABSTRACT FROM AUTHOR]

A theoretical model for energy selective electron (ESE) heat pumps operating with two-dimensional electron reservoirs is established in this study. In this model, a double-resonance energy filter operating with a total momentum filtering mechanism is considered for the transmission of electrons. The optimal thermodynamic performance of the ESE heat pump devices is also investigated. Numerical calculations show that the heating load of the device with two resonances is larger, whereas the coefficient of performance (COP) is lower than the ESE heat pump when considering a single-resonance filter. The performance characteristics of the ESE heat pumps in the total momentum filtering condition are generally superior to those with a conventional filtering mechanism. In particular, the performance characteristics of the ESE heat pumps considering a conventional filtering mechanism are vastly different from those of a device with total momentum filtering, which is induced by extra electron momentum in addition to the horizontal direction. Parameters such as resonance width and energy spacing are found to be associated with the performance of the electron system. [ABSTRACT FROM AUTHOR]

The operation characteristics of a microscopic energy selective electron (ESE) engine system that operates respectively as heat engine, refrigerator or heat pump is extensively explored. The relationship between the transmission probability function and the electron engine operating regime is discussed in detail. The optimal performance for the electron engine system operating in different modes (heat engine, refrigerator, or heat pump) with different transmission probability functions and operating regimes are systematically studied with the optimization methods of finite time thermodynamics. Moreover, impacts of the electron engine design parameters such as phonon heat leakage, resonance width and central energy level on performance characteristics for the device with different transmission probability functions are investigated. The influences of transmission probability functions are analyzed by the performance comparisons between the ESE engine system considering a Lorentz transmission probability function and that considering a rectangular transmission probability function. [ABSTRACT FROM AUTHOR]

A model of a single-barrier solid-state thermionic refrigerator with external heat transfer is established in this paper. The performance of the refrigerator is analyzed and optimized by using the combination of finite-time thermodynamics and nonequilibrium thermodynamics. The general expressions for cooling load and coefficient of performance (COP) of the refrigerator are derived. The optimum regions of cooling load and COP are obtained and the effects of the heat reservoir temperature and thermal conductance of the barrier material on the performance of the refrigerator are analyzed by detailed numerical examples. The results obtained are compared with those obtained by using traditional analysis without considering external heat transfer. For the fixed total heat transfer surface area of two heat exchangers, the ratios of the heat transfer surface area of the hot-side heat exchanger to the total heat transfer surface area of the heat exchangers are optimized for maximizing the cooling load and COP of the refrigerator, respectively. The effects of the total heat transfer surface area and the applied voltage on the optimum performance of the refrigerator are analyzed. The results obtained herein may provide some theoretical guidelines for the design and application of practical solid-state thermionic refrigerators. [ABSTRACT FROM AUTHOR]