Intermittent feeding

Goodrick, C. L., Ingram, D. K., Reynolds, M. A., Freeman, J. R., and Cider, N. (1990). Effect of intermittent feeding upon body weight and lifespan in inbred mice Interaction of genotype and age. Mech. Ageing Dev. 55, 69-87. 

Ahmed RS, Price SC, Grasso P, et aL 1989. Effects of intermittent feeding of rats with di-2-etbylhexylphthalate. Biochem Soc Trans 17 1073-1074. 

Pilot-scale NF experiments were carried out with intermittent feed dilution using spirally wound membrane modules to extract at least 98% of NaSCN free of most impurities. Among the membrane types tested, PERMA-250 gave optimum results and was chosen for detailed studies. Pilot-plant data were consolidated and fed into a simulation software developed in Microsoft Excel to provide design of a commercial NF plant capable of handling 8 m /day of 10% NaSCN feed solution containing 2% % impurities. 

Administration of 2,4-DNP by continuous intermittent feeding is less lethal to rats than a single bolus dose by gavage. Rats treated once by gavage had 50% mortality at exposure levels as low as 30 mg/kg, with 100% mortality observed at 60 mg/kg (Dow Chemical Co. 1940, 1950). In dietary studies, rats survived a 30-day treatment with 110 mg/kg/day 2,4-DNP, and the life span was not decreased in rats exposed to 40 mg/kg/day (Pugsley 1935 Tainter 1938). Under most circumstances, dietary studies in animals may be more relevant than single bolus studies to current oral exposure of humans to 2,4-DNP. 

Continuous Versus Intermittent Feeding of Sorbent. Two tests were conducted to determine whether the time-averaged SO2 removal efficiency and sorbent utilization could be increased by intermittent sorbent injection as compared to continuous feeding. Number 1 NaHCOs (69 pm) was used in both tests. The baghouse temperature was 400°F and cycle time was 20 minutes. The results are given in Table III. 

The location of the sorbent injection point appears to be important if coarser materials are used. However, with 32-pm sodium bicarbonate, there was no difference between injecting sorbent immediately before the baghouse and injecting 26 feet upstream in the flue gas duct. It was also found that continuous injection of sorbent produces better results than intermittent feeding. 

Matelova V, Brecka A, Matouskova J (1972) New method of intermittent feeding in penicillin biosynthesis. J Appl Microbiol 23 669-670... 

Shao, X., Lynd, L., Wyman, C., and Bakker, A. (2009) Kinetic modeling of cellulosic biomass to ethanol via simultaneous saccharification and fermentation part 1. Accommodation of intermittent feeding and analysis of staged reactors. BiotechnoL Bioeng.,... 

Other biocides that are stable in the system are effective only at high concentrations. In addition, they are more expensive however, they are not hazardous to materials of construction. Hence, close control of their concentrations is not necessary. The modern tendency is to use such biocides in an intermittent feed system, adding a shot to restore the shock concentration that kills all troublesome organisms or breaks up slime when the concentration has fallen to 25% of that value. This method often gives effective control (though not always), and of course, it is much cheaper than maintaining a continuous level. The theoretical depletion of the biocide from the system is given by... 

The purpose of the loop is to provide a reservoir of slack material that the much quicker feed or rollformer can draw from upon start-up while the less responsive unwinder accelerates to line speed, and, in turn, to absorb the material that is unwound while the unwinder decelerates at its slower rate when the line stops. It also allows the unwinder to run at a fairly constant speed during continuous operation even though the rate of consumption is constantly changing due to the intermittent feed motion. 

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