Dual duct

Dual duct unit An air terminal unit assembly consisting of two-ducted air inlets and a means of automatically adjusting the mixing ratio of the two air streams. 

Figure 28.6 Dual duct supplying separate zones...

Example 28.6 A dual-duct system supplies air at 14°C dry bulb, 75% saturation through one duct, and at 25°C dry bulb, 45%... 

This example gives an indication of the small and usually acceptable variations found with a well-designed dual-duct system. Since a constant total flow is required with the basic dual-duct circuit, a single fan may be used, blowing into cooling and heating branches. Where variation of volume is employed, one or two fans may be used, as convenient for the circuit. In all cases an independent extract fan and duct system will be required, so that the proportion of outside/recirculated air can be controlled. 

Gaggioli, R.A., Wepfer, W.J., and Elkouh, A.F. "Available Energy Analysis for HVAC, I. Inefficiencies in a Dual-Duct System." Energy Conservation and Building Heating and Air-conditioning Systems, A.S.M.E. 

Dual Duct System - An air conditioning system that has two ducts, one is heated and the other is cooled, so that air of the correct temperature is provided by mixing varying amounts of air from each duct. 

Convert dual-duct systems to coohng-only VAV systems if separate perimeter heating is installed. 

Dual cure sites Ductile iron Ductile particles Duct silencers Dugro [7681-76-7]... 

The concrete block walls of the cell housing the generator tube and associated components are 1.7 meters thick. The facility also includes a Kaman Nuclear dual-axis rotator assembly for simultaneous transfer and irradiation of reference and unknown sample, and a dual Na iodide (Nal) scintillation detector system designed for simultaneous counting of activated samples. Automatic transfer of samples between load station to the rotator assembly in front of the target, and back to the count station, is accomplished pneumatically by means of two 1.2cm (i.d.) polyethylene tubes which loop down at both ends of the system and pass underneath the concrete shielding thru a pipe duct. Total one-way traverse distance for the samples is approx 9 meters. In performing quantitative analysis for a particular element by neutron activation, the usual approach is to compare the count rates of an unknown sample with that of a reference standard of known compn irradiated under identical conditions... 

Weaving Atomizers on PI versus Well Water ACP-1. Figure 4 shows the well water to DI transition for a weaving operation on 100% cotton and for which the air-conditioning consists of a "dry duct". That is, the weave room environmental conditions are controlled by a mix of inside and outside air and humidity is controlled solely by atomizers. Low solids water was provided with dual bed, cation/anion deionization (DI) equipment. 

The initial sampling site (runs 1-12) was an existing 3-in. port on the west side of the south duct leading from the induced draft fan to the stack. This duct was one of two parallel ducts between the electrostatic precipitator and the stack. Three dual tests (13-18) were performed in the north side of the same duct where a 6-in. port had been installed. 

Feldman et al. (1979a,b) were the first to demonstrate a reduction in cholesterol absorption due to dietary stearic acid in rats. The investigators used three different methods to quantify cholesterol absorption (i.e., plasma isotope ratio method, fecal dual isotope method, and lymph duct can-nulation), and in each case absorption was significantly decreased by stearic acid. Other studies using lymph duct cannulated rats fed stearic acid-enriched diets showed significant reductions in cholesterol absorption (Chen et al., 1989 Ikeda et al., 1994). Using a more realistic dietary approach,... 

Capillary gap cell — The undivided capillary gap (or disc-stack) cell design is frequently used in industrial-scale electroorganic syntheses, but is also applicable for laboratory-scale experiments when a large space-time yield is required. Only the top and bottom electrodes of c.g.c. (see Figure) are electrically connected to - anode and cathode, respectively, whereas the other electrodes are polarized in the electrical field and act as -> bipolar electrodes. This makes c.g.c. s appropriate for dual electrosynthesis, i.e., pro duct-generating on both electrodes. 

Background. Biliary complications both intra- and extrahepatic following administration are due to the embolic and radiation induced necrosis of the biliary ducts [29]. In contrast to the normal liver parenchyma, the intrahepatic bile ducts do not have a dual blood supply and are fed exclusively from the hepatic arterial branches that give off a vascular plexus (peribiliary capillary plexus) around the bile ducts. This microscopic peribiliary arterial plexus has a similar diameter to that of the microspheres (10-60 pm, mean 35 pm). Therefore, ischaemia of the intrahepatic bile ducts can occur after radioembolization [25]. 

Balachandran et al. (2007) also showed several ways to increase the H2 production rate by H2O decomposition via MIEC membranes. Producing CGO/Ni membranes with a finer microstructure enlarged the triple-phase-boundary area and increased the H2 production rate to = 10 cm (STP)/min.cm. Using a single-phase, mixed-con-ducting membrane (SrFeCoo.50x(SFC2)) also produced higher H2 production rates relative to dual-phase cermet membranes. 

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