Under-inhibited

An important recent development is the consideration of under-inhibited systems, as reported by Austvik and coworkers, (Austvik et al., 1995 Gjertsen et al., 1996). Yousif et al. (1996) measured two adverse effects of small amounts of methanol on hydrate inhibition (1) insufficient inhibition with methanol enhances the rate and amount of hydrates that form and (2) hydrates that form with... 

Case Study 5 Under-Inhibition by Methanol in a Gas Line... 

Flow assurance engineers for a major energy company (Mehta et al., 2003) indicate that for a two year periods, one of their offshore gas flowlines operated well inside the hydrate formation region. The problem arose from increased water production (to >1000 BPD) over the field life, with limited methanol delivery. Their approach was to inject as much methanol as possible, in the knowledge that they were underinhibiting the system. Due to under-inhibition, there was a gradual increase in the pressure drop (A P) in the line over a period of about 2 weeks, indicating a hydrate build-up on the walls. 

Daumann J, Heekeren K, Neukirch A, Thiel CM, Moller-Hartmann W, et al. 2008. Pharmacological modulation of the neural basis underlying inhibition of return (IOR) in the human 5-HT(2A) agonist and NMDA antagonist model of psychosis. Psychopharmacology 200 573-583. 

Although there is still considerable controversy about the relative importance of the different possible modes of pyrolysis of saturated hydrocarbons under inhibiting conditions, it is generally agreed that the uninhibited reactions proceed principally by a radical chain mechanism. 

De Vry, J., Schreiber, R., Eckel, G. and Jentzsch, K.R. (2004) Behavioral mechanisms underlying inhibition of food-maintained responding by the cannabinoid receptor antagonist/inverse agonist SR141716A, Eur J Pharmacol, 483 55-63. 

Dawson, J.F. and Holmes, C.F.B., Molecular mechanisms underlying inhibition of protein phosphatases by marine toxins. Front BioscL, 4, d646, 1999. 

Development of a Generalized Kinetic Model for One-Substrate Reactions Under Inhibition... 

Figure 24.3 Sensorgrams derived from an SPR-biosensor analysis of biotin. Superimposed sensorgrams of biotin calibration standards (a) 1.23 ng/mL (b) 3.7ng/mL (c) 11.1 ng/mL (d) 33.3ng/mL (e) lOOng/mL. SPR-based biosensor assay utilizing a biotin spectfic antibody under inhibition conditions (1) baseline with buffer flow (2) sample injection (3) binding association phase (4) end of injection (5) stable binding response acquired (6) surface regeneration (7) baseline for subsequent cycle.

Yamamoto, T., Terada, N., Seiyama, A., Nishizawa, Y., Akedo, H., and Kosaka, H. (1998). Increase in experimental pnhnonary metastasis in mice by L-aiginine under inhibition of nitric oxide production by NG-nitro-L-arginine methyl ester. Int. J. Cancer 75(1), 140-144. 

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