Flow rate range

The bubble size in these cells tends to be the smallest (10 to 50 Im) as compared to the dissolved-air and dispersed-air flotation systems. Also, very httle turbulence is created by the bubble formation. Accordingly, this method is attractive for the separation of small particles and fragile floes. To date, electroflotation has been applied to effluent treatment and sludge thickening. However, because of their bubble generation capacity, these units are found to be economically attractive for small installations in the flow-rate range of 10 to 20 mVh. Electroflotation is not expected to be suitable for potable water treatment because of the possible heavy metal contamination that can arise due to the dissolution of the electrodes. 

The maximum and minimum flow rate available from the solvent pump may also, under certain circumstances, determine the minimum or maximum column diameter that can be employed. As a consequence, limits will be placed on the mass sensitivity of the chromatographic system as well as the solvent consumption. Almost all commercially available LC solvent pumps, however, have a flow rate range that will include all optimum flow rates that are likely to be required in analytical chromatography... 

It is seen that the optimum flow rate ranges from about 1.3 ml/min to about 65 pi... 

Plow rate has a tremendous effect on resolution with aqueous GFC as shown in Fig. 4.20. Lower flow rates will decrease HETPs (up to a point) and increase resolution. In general, a flow rate range of 0.5-0.8 ml/minute is recommended for TSK-GEL PW analytical columns. 

H type columns must be used at a flow rate and pressure drop below maximum values listed in Tables 4.12-4.16. Standard flow rates are also listed in these tables. They are flow rate range recommendable for long-term usage in tetrahydrofuran at 25°C and vary with temperature. H type columns can be operated at a higher flow rate at elevated temperatures. They also vary with solvent depending on the viscosity. They are approximately inversely proportional to the solvent viscosity. The maximum pressure drop listed in the tables is for one column. When some columns are used in series, the total maximum pressure drop is a summation of values of all columns. 

OS 7] [R 22] [P 5] Reactions were performed with wide variations of flow rates, ranging from 5 25 5 to 300 1000 300 (each value in ml h ) [78]. The corresponding yields were all about 75%. These yields are of the same order as for laboratory-batch operation [82]. 

Thus, the column diameters chosen for the two dimensions are determined by the amount of sample available and will dictate the flow rate ranges available to use. In split-flow systems, where only a portion of the first-dimension effluent is injected into the second dimension, the choice of column size is unlimited and the two methods can be developed independently. In comprehensive systems where the entire sample from the first dimension is injected into the second dimension, the flow rates are generally lower in the first dimension to accommodate the lower injection volumes into the second dimension. For example, for a 1-mm ID column in the first dimension with a flow rate of 50 (tL/min and a sampling rate of 1 min, 50 pL could be injected onto the second dimension. A 50-(lL injection onto a4.6-mm ID column flowing at 1 mL/min should be accommodated fairly well based upon its composition. In Chapter 6, the first dimension column diameters are estimated based upon the injection volume and sampling rate into the second dimension. 

Flow rate and extraction time. Dynamic techniques for the extraction of carotenoids with SC-CO2 use flow rates that vary from 0.5 to 15 mL/min (measured at extraction temperature and pressure) with different effects depending on the matrix (Rozzi and others 2002 Subra and others 1998 Saldana and others 2006). Subra and others (1998) extracted (3-carotene from 1 to 2.5 g freeze-dried carrots and studied the effect of flow rates (0.4 and 1.2 liter/min) they obtained higher yields of (3-carotene at a flow rate of 1.2 liter/min. Sun and Temelli (2006) also evaluated the effect of flow rate (0.5 and 1.0 liter/min) on the extraction of (3-carotene with SC-CO2 + canola oil. The total carotenoids yield increased with flow rate, ranging from 934.8 to 1,973.6 pg/g dry carrot at C02 flow rates from 0.5 to 2 liter/min (measured at STP), respectively (Sun and Temelli, 2006). However, the lycopene yield decreased from 38.8% to 8% as flow rate was increased from 2.5 to 15 mL/min (measured at extraction temperature and pressure) (Rozzi and others 2002). 

Table 130 Rate enhancement observed after adding 1 %Pt to various oxides for high temperature shift carried out at 450 °C using a feed containing 9%CO, 9%HzO, balance N2 with flow rates ranging between 150 and 600 cm3/min538...

Fuel flow rate. Your instructor will show you how to vary the fuel flow rate to the burner head and also how to read the flow rate on the flow meter. Measure absorbance values at ten different flow rates, selecting a flow rate range that will maintain a flame while bracketing what the manufacturer s literature or your instructor may suggest as the optimum. 

Note that Vg is proportional to the square of the inner radius of the column. It is important to have a rough idea of the void volume of the column since it often dictates the operating flow-rate range, sampleloading capacity, and mass sensitivity (the minimum detectable amount) of the assay. For instance, a typical analytical column (150mm x 4.6mm i.d.) has a Vg of about 1.5 mL and is operated at 1.0mL/min. In contrast, by reducing the inner diameter to 2.0 mm, a typical LC/MS column (150mm X 2.0mm i.d.) has a Vg of about 0.3mL and is operated at... 

Very low flow electrospray is called nanoelectrospray [26] where the samples are infused into the mass spectrometer at the nanoliter flow rate range. The infusion of a few microliters will result in a stable signal for more then 30 min, using pulled capillaries or chip-based emitters [27]. With infusion, signal averaging allows to improve the limit of detection in tandem mass spectrometry. Nanoelectrospray is particularly important in combination with nanoflow liquid chromatography or chip-based infusion for the analysis of peptides and proteins. 

Nanoelectrospray ionization flow rates range from a few nanoliters per minutes to a few hundred nanoliters per minutes nanoelectrospray is performed with pulled capillaries or on chips which serve as emitter... 

The once-through cooling system flow rate range of 239 steam electric power generation plants using coal is 0.189-6,280,000 m /plant (mean 1,130,000 m / plant), which is equal to 0.001-209,000 mVMW (mean 4,310,000 m /MW). 

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