Yang cycle

Ethylene is produced in plants in a complex series of reactions known as the Yang cycle (after its discoverer, S. F. Yang) that starts with the amino acid methionine. 

Biosynthesis ofethyiene in plant tissue. The upper cycle is known as the Yang cycle. The two methylene groups of S-adenosyl-L-methionine finally give rise, via the two methylene groups of ACC, to the two carbon atoms of ethylene (indicated by the solid circles). A = Adenine. 

Bannister, R. L. Newby, R. A. and Yang, W.-C. (1999). Final Report on the Development of a Hydrogen-Fueled Gas Turbine Cycle for Power Generation. Tr3ns3ctions of the ASME, Journ3l of Engineering for Gas Turbines 3nd Power 121 38-45. 

To evaluate wear properties of the PFAM film, the friction after 20 K flying cycles was measured by Yang et al. [28] and Hu et al. [26] as shown in Fig. 9. Each cycle of the takeoff and landing process was performed within 2 min. The existence of the PFAM film has no influence on the normal takeoff and landing of the slider. In the case of 50 ppm and 500 ppm, the PFAM film maintained a low friction at the last cycle in a CSS test. The maximum friction value of the latter is less than 2 g, which is about one-third of that of the bare... 

Aksoy MO, Yang Y, Ji R, et al. CXCR3 Surface expression in human airway epithelial cells cell cycle dependence and effect on cell proliferation. Am J Physiol Lung Cell Mol Physiol 2005 290(5) L909-918. 

Although PSA is a batchwise process, by using multiple beds in a sequential manner the overall process is operated in a continuous fashion. Each bed may contain layers of different adsorbent materials selective for specific contaminants in the hydrogen gas stream to be purified. Each bed undergoes a sequence of four basic steps in a PSA cycle adsorption, depressurization, purge at low pressure, and repressurization. This sequence of cyclic operations for each bed is shown schematically for a four-bed PSA process in Figure 8.4 (Yang, 1987 Cassidy, 1980 Miller and Stocker, 1999). 

Cocurrent depressurization, purge, and pressure-equalization steps are normally added to increase efficiency of separation and recovery of product. At the end of the adsorption step, the more weakly adsorbed species have been recovered as product, but there is still a significant amount held up in the bed in the inter- and intraparticle void spaces. A cocurrent depressurization step can be added before the blowdown step, which is countercurrent to adsorption. This increases the amount of product produced each cycle. In some applications, the purity of the more strongly adsorbed components has also been shown to be heavily dependent on the cocurrent depressurization step [Cen and Yang, Ina. Eng. Chem. Fundam., 25, 758-767 (1986)]. This cocurrent blowdown is optional because there is always a countercurrent one. Skarstrom developed criteria to determine when the use of both is justified [Skarstrom in Li, Recent Developments in Separation Science, vol. II, CRC Press, Boca Raton, pp. 95-106 (1975)]. 

F. Wu, F. Yang, KC Vinnakota, and DA Beard, Computer modeling of mitochondrial tricarboxylic acid cycle, oxidative phosphorylation, metabolite transport, and electrophysio logy. J. Biol. Chem. 282(34), 24525 24537 (2007). 

Three C60 derivatives with two to four malonic acid groups (DMA C60, TMA C60, and QMA C60) were prepared and the phototoxicity of these compounds against HeLa cells was determined by MTT assay and cell cycle analysis (Yang et al., 2002). The relative phototoxicity of these compounds was DMA C60 > TMA C60 > QMA C60. Hydroxyl radical quencher mannitol (lOmM) was not able to prevent cells from the damage induced by irradiated DMA C60. DMA C60, together with irradiation, was found to decrease the number of G(l) cells from 63% to 42% and increase G(2) + M cells from 6% to 26%. 

Further discussions of pressure swing adsorption, parametric pumping and cycling-zone adsorption have been presented by Yang 3-1, Schweitzer 7 1 and Wankat(58). 

Li Y, Shan F, Wu JM, Wu GS, Ding J, Xiao D, Yang WY, Atassi G Leonce S, Caignard DH, Renard R (2001) Novel antitumor derivatives targeting G1 phase of the cell cycle. Bioorg Med Chem Lett 11 5-8. 

Ko, W. I., Kim, H. D. Yang, M. S. 2002. Radioactive waste arisings from various fuel cycle options. Journal of Nuclear Science and Technology, 39, 200-210. 

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