Davis cycle

We adopt the nomenclature introduced by Hawthorne and Davis [1], in which compressor, heater, turbine and heat exchanger are denoted by C, H, T and X, respectively, and subscripts R and I indicate internally reversible and irreversible processes. For the open cycle, the heater is replaced by a burner, B. Thus, for example, [CBTX]i indicates an open irreversible regenerative cycle. Later in this book, we shall in addition, use subscripts... 

The analysis of Hawthorne and Davis [1] for irreversible a/s cycles is developed using the criteria of component irreversibility, firstly for the simple cycle and subsequently for the recuperative cycle. In the main analyses, the isentropic efficiencies are used for the turbomachinery components. Following certain significant relationships, alternative expressions, involving polytropic efficiency and. tc and jcj, are given, without a detailed derivation, in equations with p added to the number. 

The Hawthorne and Davis approach thus aids considerably our understanding of a/s plant performance. The main point brought out by their graphical construction is that the maximum efficiency for the simple [CHT]i cycle occurs at high pressure ratio (above that for maximum specific work) whereas the maximum efficiency for the recuperative cycle [CHTX]i occurs at low pressure ratio (below that for maximum specific work). This is a fundamental point in gas turbine design. 

The nomenclature introduced by Hawthorne and Davis [4] is adopted and gas turbine cycles are referred to as follows CHT, CBT, CHTX, CBTX, where C denotes compressor H, air heater B, burner (combustion) T, turbine X, heat exchanger. R and I indicate reversible and irreversible. The subscripts U and C refer to uncooled and cooled turbines in a cycle, and subscripts 1,2, M indicate the number of cooling steps (one, two or multi-step cooling). Thus, for example, [CHT] C2 indicates an irreversible cooled simple cycle with two steps of turbine cooling. The subscript T is also used to indicate that the cooling air has been throttled from the compressor delivery pres.sure. 

In their original air standard cycle analysis, using constant specific heats, Hawthorne and Davis 4 considered the dry [CBTIiXr cycle. They assumed a perfect heat exchanger, with the specific heats of gas and air constant and identical, so that Ty becomes equal to Tj in Fig. 6.6. From their examination of the enthalpy-entropy diagram of this... 

Flinn, S., Gregory, J., McNaughton, L. R. Tristan, S., and Davies, R., Caffeine ingestion prior to incremental cycling to exhaustion in recreational cyclists, International Journal of Sports Medicine, 11, 188, 1990. 

Observations from various systems, including yeast, suggest that phosphorylation and dephosphorylation of proteins play important roles in the mitotic and meiotic cell cycles and the differentiation of germ cells. Extracts from mitotic HeLa cells contained phosphoproteins also present in other mitotic and meiotic cell types, but not in interphase cells (Davis et al., 1983). Exposure of Xenopus oocytes to progesterone results in a burst of protein phosphorylation shortly before GVBD (Mailer et al.,... 

There are also voices critical of the rTCA cycle Davis S. Ross has studied kinetic and thermodynamic data and concludes that the reductive, enzyme-free Krebs cycle (in this case the sequence acetate-pyruvate-oxalacetate-malate) was not suitable as an important, basic reaction in the life evolution process. Data on the Pt-catalysed reduction of carbonyl groups by phosphinate show that the rate of the reaction from pyruvate to malate is much too low to be of importance for the rTCA cycle. In addition, the energy barrier for the formation of pyruvate from acetate is much too high (Ross, 2007). 

Leckie, J.O. and J.A. Davis. 1979. Aqueous environmental chemistry of copper. Pages 89-121 in J.O. Nriagu (ed.). Copper in the Environment. Part 1 Ecological Cycling. John Wiley, NY. 

J. P. Davies A. R Grossman (1994) Sequences controlling transcription of the Chlamydomonas l -tubulin gene after deflagellation and during the cell cycle. Mol. Cell. Biol., 14 5165-5174... 

Davis T, Kennedy C, Chiew YE, Clarke CL, deEaxio A. (2000) Histone deacetylase inhibitors decrease proliferation and modulate cell cycle gene expression in normal mammary epithelial cells. Clin Cancer Res 6 4334 342. 

DAVIES EQUATION DEBYE-HOCKEL TREATMENT Day-night cycle,... 

Lawrence TS, Davis M, Tang HY, et al. Fluorodeoxyuridine-mediated radiosensitization of human colon cancer cells is not caused by cell cycle redistribution. ProcAACR 1992 33 502, (abstr 3002). 

Davies WL, Gloor WT Jr. Batch production of pharmaceutical granulation in fluidized bed III binder dilution effects on granulation. J Pharm Sci 1973 62 170. Rawley FA. Effects of the bag shaking cycle on the particle size distribution of granulation. Pharm Technol 1989 13(9) 78-82. 

To use activity coefficients, first solve the equilibrium problem with all activity coefficients equal to unity. From the resulting concentrations, compute the ionic strength and use the Davies equation to find activity coefficients. With activity coefficients, calculate the effective equilibrium constant K for each chemical reaction. K is the equilibrium quotient of concentrations at a particular ionic strength. Solve the problem again with K values and find a new ionic strength. Repeat the cycle until the concentrations reach constant values. 

The solar neutrino problem was identified by the first results of Davis et al. using the Cl detector at the Homestake Mine. Davis et al. observed only about one-third of the expected solar neutrino flux as predicted by standard models of the sun, which assume 98.5% of the energy is from the pp chain and 1.5% of the energy is from the CNO cycle. The final result of the Cl detector experiment is that the observed solar neutrino flux is 2.1 + 0.3 SNU compared to the predicted 7.9 + 2.4 SNU, where the solar neutrino unit (SNU) is defined as 10-36 neutrino captures/second/target atom. The GALLEX and SAGE detectors subsequently reported solar neutrino fluxes of 77+10 SNU and 69+13 SNU, which are to be compared to the standard solar model prediction of 127 SNU for the neutrinos detected by these reactions. 

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