Chien’s model

Section 9.7.4.S) is another main termination process in Chien s model for polymerization with metallocene/MAO catalysts. Show how the rate constant (A ) of chain transfer by jS-H elimination can be calculated from the polymer molecular weight data. 

Huang, Y., Rumschitzki, D., Chien, S. and Weinbaum, S. (1997) A fiber matrix model for the filtration through fenestral pores in a compressible arterial intima. Am. J. Physiol, 272, H2023-H2039. 

J. Y. Chien, S. Eriedrich, M. A. Heathman, D. P. de Alwis, and V. Sinha, Pharma-cokinetics/pharmacodynamics and the stages of drug development Role of modeling and simulation, AAPS J. 7 (2005), E544-E559. 

Such a different conclusion can be understood by considering the difficulties connected to the experimental determination and the definition of Thiele modulus parameters, such as So and D. According to Chien, S means the catalyst primary particle size with a value of about 10 cm for a-TiCIj instead, in the Multigrain model, Sp seems to correspond to the size of the whole catalyst granule. 

Chien S (2007) Ischemic rabbit ear model created by minimally invasive surgery. Wound Repair Regen 15 928-935... 

Chien s kinetic model [48,49], unlike Ewen s model described above, is for the systems in which more than one active species is present. The model assumes the presence of multiple active center types, chain transfer to MAO, chain transfer by /3-H elimination (see p. 801), and first-order deactivation reactions of active centers. Chien applied the model in the study of ethylene polymerization with Cp2ZrCl2/MAO catalyst and propylene polymerization with Et(Ind)2ZrCl2/MAO and Et(H4lnd)2ZrCl2/MAO catalysts. 

Collins has reported the synthesis of a related class of metallocenes (43), some of which form elastomeric, stereoblock polypropylene when activated by The elastomeric properties of the polymer formed using 43 (M = Hf, X = SiMe2 7)xn = 25 °C) were far superior to those formed by the other metallocenes in the study. The polymers made using 42 and 43 have similar microstructures, as well as physical and mechanical properties. However, after detailed microstructural analysis of the polymer the authors proposed an alternate mechanism of stereocontrol to Chien s site epimerization model (Scheme... 

Cheng, H.C., Chien, H., Liao, C.H., Yang, Y.Y., and Huang, S.Y. 2007. Carotenoids suppress proliferating cell nuclear antigen and cyclin D1 expression in oral carcinogenic models. J Nutr Biochem 18 667-675. 

Kuhl, A. L., R. E. Ferguson, K. Y. Chien, J. P. Collins, and A. K. Oppenheim. 1995. Gasdynamic model of turbulent combustion in an explosion. Combustion, Detonation, Shock Waves. Zel dovich Memorial Proceedings. Eds. A. G. Merzhanov and S. M. Frolov. Moscow ENAS Publ. 1 181-89. 

In the chain-of-rotators (COR) equation proposed by Chien, Greenkom, and Chao [17], a chain molecule is modeled as joined spheres in which adjacent covalent bonds can rotate. Rotation takes place because the chain is not straight any two adjacent bonds are joined at an angle like the radials from the center of a pyramid to the four comers. Chien et al. found the pressure of rotation by comparing the pressure of Boublik and Nezbeda s hard dumbbell fluid [18] with the pressure of Carnahan and Starling s hard spheres. The rotational pressure found is... 

Jones RDO, Jones HM, Rowland M, Gibson CR, Yates JWT, Chien JY, Ring BJ, Adkison KK, Ku MS, He H, Vuppugalla R, Marathe P, Fischer V, Dntta S, Sinha VK, Bjornsson T, Lave T, Ponlin P. 2011a. PhRMA CPCDC initiative on predictive models of hnman pharmacokinetics. 2. Comparative assessment of prediction methods of hnman volnme of distribution. J Pharm Sci 100 4074-4089. 

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