Solar engine is discussed as integration of solar collector with linear heat loss and Curzon-Ahlborn engine is considered. This simple endoreversible model is used to discuss some applications of results of endoreversible heat engine in the field of solar engine. Optimum operating temperature of the solar collector and relevant maximum overall efficiency of solar engine is calculated, the results being compared with those by the models where Carnot and Curzon-Ahlborn efficiences were used. Conclusions obtained for endoreversible model are used for simple optimal design of solar engine. The size of heat engine for a given solar collector is optimized. The investment costs of solar collector and heat engine per unit of output power are used as optimization criterion. and Obsahuje seznam literatury
Notopronocephalus peekayi gen. et sp. n. is described from the intestine of Elseya latistemum Gray, 1867, E. dentata (Gray, 1863) and Emydura signala Ahi, 1932 from rivers in Queensland. The new genus is distinguished by the absence of ventral glands, simple (neither diverticulate nor sinuous) caeca terminating at the anterior margin of the testes, excretory arms not uniting in forebody, single ovary, two opposite testes close to the posterior end of the body, intracaecal genital pore, vitelline follicles anterior to the testes, cirrus-sac orientated obliquely and not divided into two portions, and the uterus intracaecal. This is the first pronocephalid to be described from an Australian freshwater turtle and the first from the family Chelidae.
The Family Library of the noblemen Nostitz and Rieneck has been housed in the Nostitz Palace in Prague since the 1770s, now administered by National Museum Library. Some of the 14,000 copies reused a parchment book binding which had been originally used in liturgical books from the 14th and 15th centuries. The article dissects sixty-six parchment book bindings with notations: the key part of the study provides a list of these book bindings with details about each book: the musical content of fragments, their notation, and dating. This list is introduced by a text on the history of the Nostitz Library, paying special attention to the incorporated Castle library of Otto Jr. of Nostitz (1608–1665), originally from Jawor in Lower Silesia. Since the vast majority of the notated bindings were detected on books signed by Otto Jr. of Nostitz, the musical-palaeographical analysis of the fragments also examines possible influences of the Polish notation tradition.