A hybrid in situ bioremediation/pulsed pumping strategy has been developed to cost effectively remediate a carbon tetrachloride plume in Schoolcraft, Michigan. The pulsed pumping system uses a line of alternating injection and extraction wells perpendicular to the direction of natural groundwater flow. The wells pump periodically to clean the recirculation zone between adjacent wells. During th...

This paper presents a numerical analysis using the CFD Fluent (6.3.26 version) program to identify the effects that can be generated when using radiant tubes with internal recirculation of combustion products, but with a pre-combustion chamber. The numerical results are validated with an experimental assembly based on the outlet deviation of gases temperature. These deviations were less than 5 ...

The free radical trapping agents NXY-059 and alpha-phenyl-N-tert.-butylnitrone (PBN) markedly reduce infarct volume, even when given 1 or 3 h after the start of recirculation, following 2 h of middle cerebral artery (MCA) occlusion in rats. Their anti-ischemic effects are shared by the two immunosuppressants cyclosporin A (CsA) and FK506. Interestingly, CsA causes an additional reduction in inf...

Previous therapeutic studies on the prevention of selective vulnerability of neurons in the hippocampus have suggested that the critical period for induction of delayed neuronal injury occurs early during recirculation. To determine the onset and duration of this period, an ultrashort-acting barbiturate (methohexital) was infused into the left carotid artery of 47 gerbils after various times of...

A mathematical model for the prediction of internal recirculation of complex impinging stream reactors has been presented. The model constitutes a repetition of a series of ideal plug flow reactors and CSTR reactors with recirculation. The simplicity of the repeating motif allows for the derivation of an algebraic relation of the whole system using the Laplace transform. An impinging stream...

This study generated eddy covariance data to investigate atmospheric dynamics leeward of a small, forested hillside in upstate New York. The causes and effects of recirculation eddies were examined to support the larger goal of improving measurement of the exchange of energy, moisture, and trace gases between the terrestrial biosphere and the atmosphere over complex terrain. Sensors operated at...

Introduce electronic control exhaust gas recirculation EGR system in the passenger cars and light duty vehicles was made because of fuel direct injectionengines. In this engines temperature combustion process is a higher then other type engine and in this connections NO, emissions were higher to. Simultaneously was appearing problems to electronic exhaust gas recirculation control in connection...

The purification capacity of a laboratory scale tidal flow reed bed system with final effluent recirculation at a ratio of 1:1 was investigated in this study. In particular, the four-stage reed bed system was heavily loaded with strong agricultural wastewater. Under the hydraulic and organic loading rates of 0.43 m3/m2.d and 1055 gCOD/m2.d, respectively, the average removal efficiencies obtaine...

On July 25, 2012, SBV infection was identified in a cow in Jura Canton in the northwestern, French-speaking region of Switzerland (Romandie) (7). A serologic study conducted in the United Kingdom showed that several cattle and sheep seroconverted for SBV in 2012 (8). However, our data show that SBV survived the winter, when midge numbers decreased. The precise mechanisms of SBV overwintering ar...

There is an increasing need to operate power plants at low load for longer periods of time. When a once-through boiler operates at a sufficiently low load, recirculation is introduced, significantly altering the control structure. This paper illustrates the possibilities for using constrained control to obtain optimal load gradients in the recirculation mode. A model predictive controller is de...