Measurement of liquid

The greatest quantitative errors in semi-micro work arise in connection with the measurement of liquids. For this reason the use of microburettes and graduated dropping-tubes is essential cf. pp. 59-60). 

Prost and Le Golf (P6) reported measurements of liquid holdup for co-and countercurrent flow of air and a 70% aqueous solution of saccharose... 

Pirie. R. L., Davies, T., Khan, A. R. and Richardson, J. F. 2nd International Coni, on Flow Measurement — BHRA, London (1988) Paper F3, 187. Measurement of liquid velocity in multiphase flow by salt injection method. 

The measurement of liquid side gas - liquid mass transfer coefficient kia, showed that the value of kia increase with increasing rotation speed (V) and gas flow rate (Qg). hi the present research, the effect of impeller rotation on mass transfer coefficient was more significant than the effect of gas flow rate. The following correlation was obtained kia =1.7 x 10 ... 

Capacitance and Surface Tension Measurements of Liquid Liquid Interfaces Zdenek Samec... 

The electrochemical circuitry required for SECM is relatively straightforward. Since the interface is not generally externally polarized in SECM measurements of liquid-liquid interfaces, a simple two-electrode system suffices (Fig. 3). A potential is applied to the tip, with respect to a suitable reference electrode, to drive the process of interest at the tip and the corresponding current that flows is typically amplified by a current-to-voltage converter. 

Measurement of liquid film thickness. A variety of techniques have been used to measure the time variation of local film thickness and the data on wave structure that can be deduced therefrom (Dukler and Taitel, 1991a) ... 

Figure 3.32 Measurement of liquid film thickness by Moire fringes (a) experimental setup and (ft) Moire pattern with liquid films of varying thicknesses. (From Kheshgi and Scriven, 1983. Copyright 1983 by Elsevier Science Ltd., Kidlington, UK. Reprinted with permission.)...

Figure 3.33 Measurement of liquid film thickness by means of a wall optical sensor as used by Ohba et al. (1984). (From Del-ha ye, 1986. Copyright 1986 by Hemisphere Publishing Corp., New York. Reprinted with permission.)... 

The value of 3 and its dispersion for a molecule, or polymer chain, can be experimentally determined by DC induced second harmonic generation (DCSHG) measurements of liquid solutions -1 2). The experimental arrangement requiring an applied DC field E° to remove the natural center of inversion symmetry of the solution is described in Figure 4. The second harmonic polarization of the solution is expressed as... 

Howell, E. 2001. Dynamic surface tension measurements of liquid solder using oscillating jets of elliptical cross section. Mechanical and Industrial Engineering. University of Illinois at Chicago, Chicago, IL. pp. 75. 

Rousar, I., and Van den Akker, H. E. A., LDA Measurements of Liquid Velocities in Sparged Agitated Tanks with Single and Multiple Rushton Turbines . 8th European Conference on Mixing, Cambridge, UK IChemE Symp. Ser., 136, 89-96 (1994). 

Barrel the unit of measurement of liquids in the petroleum industry equivalent to 42 U.S. standard gallons or 33.6 imperial gallons. 

This process has a classical on-line instrumentation gathering measurements of liquid flow rates (at the input of the reactor and in the recirculation loop), temperature and pH in the reactor and biogas flow rate and composition i.e., CO2, CH4 and H2 content in the biogas) [30]. In addition, the following sensors were installed over the years a TOC analyzer, a titrimetric sensor [3] and a FT-IR spectrometer [29]. Since 1998, this instrumentation provides us with the following on-line measurements in the liquid phase every... 

Liquidity ratios are a measure of a company s ability to pay its shortterm debts. Current ratio is obtained by dividing the current assets by the current liabilities. Depending on the economic climate, this ratio is 1.5 to 2.0 for the chemical process industries, but some companies operate closer to 1.0. The quick ratio is another measure of liquidity and is cash plus marketable securities divided by the current liabilities and is slightly greater than 1.0. 

Open-Channel Flow Measurement Open-channel flow measurements are usually based on measurement of liquid level in a flow channel constructed of a specified geometry. The two most common flow channels used are weirs and flumes. See Spitzer (2005, op. cit.). 

The results of both and Rn measurements of liquid film coefficient versus wind velocity are plotted in Figure 9.4, along with two parameterizations that will be discussed in prediction of wind influence. 

Evans, W. F. J., and E. Puckrin, Near-Infrared Spectral Measurements of Liquid Water Absorption by Clouds, Geophys. Res. Lett., 23, 1941-1944 (1996). 

A Diode-Laser-Based Automated Timing Interface for Rapid Measurement of Liquid Viscosity 42... 

Quantifying Meniscus Forces with an Electronic Balance Direct Measurement of Liquid Surface Tension 210... 

The simplest use of CST is to answer the question, Do two materials mix Chemical handbooks—e.g., (193A)—answer this question for water and sometimes for a few other solvents, usually only at room temperature. Some recent publications answer it for several other pairs (17,106,121, 211, 372). These are summarized in Tables IV to VIII of this book. CST answers the question for any temperature, since above the CST (or below the LCST) the liquids mix in all proportions, unless one component crystallizes out. CST also gives an approximate measure of liquid solubility at room temperature, or any other temperature below the CST, assuming the solubility curve is similar to Figure 1. 

Thermodynamic. The thermodynamic properties of elemental plutonium have been reviewed (35,40,41,43—46). Thermodynamic properties of solid and liquid Pu, and of the transitions between the known phases, are given in Table 5. There are inconsistencies among some of the vapor pressure measurements of liquid Pu (40,41,43,44). 

British Standard 3680 Methods of Measurement of Liquid Flow in Open Channels (1969-1983). 

Permeability is often referred to as a measure of liquid flow through a filter system and is the reciprocal of the filtration resistance. 

Hanna, G.J. and Noble, R.D. (1985) Measurement of liquid-liquid interfacial kinetics. Chemical Reviews, 85, 583. 

C. Boyer, B. Fanget, Measurement of liquid flow distribution in trickle bed reactor of large diameter with a new gamma-ray tomographic system, Chem. Eng. Sci. 57 (2002) 1079-1089. 

Liquid residence time in the packed rotor varies as a function of packing depth, packing type, rotor speed, and liquid properties (26). Two basic approaches have been applied to the measurement of liquid in the rotor. The first measure is the average residence time of the liquid within the rotor, and the second is the liquid holdup on the packing. Due to the flow patterns described previously, not all of the rotor packing is wetted and not all of the liquid resides on the packing surface. As a result, average residence time and liquid holdup are distinct measures of liquid flow, contrary to the experience with packed towers. 

Measurements of liquid density are closely related to quantity and liquid-level measurements since both are often required simultaneously to establish the mass contents of a tank, and the same physical principle may often be used for either measurement, since liquid-level detectors sense the steep density gradient at the liquid-vapor interface. Thus, the methods of density determination include the following techniques direct weighing, differential pressure, capacitance, optical, acoustic, and nuclear radiation attenuation. In general, the various liquid level principles apply to density measurement techniques as well. 

We think that judicious application of molecular simulation tools for the calculation of thermophysical and mechanical properties is a viable strategy for obtaining some of the information required as input to mesoscale equations of state. Given a validated potential-energy surface, simulations can serve as a complement to experimental data by extending intervals in pressure and temperature for which information is available. Furthermore, in many cases, simulations provide the only realistic means to obtain key properties e.g., for explosives that decompose upon melting, measurement of liquid-state properties is extremely difficult, if not impossible, due to extremely fast reaction rates, which nevertheless correspond to time scales that must be resolved in mesoscale simulations of explosive shock initiation. By contrast, molecular dynamics simulations can provide converged values for those properties on time scales below the chemical reaction induction times. Finally,... 

Which piece of glassware will give you a more accurate measure of liquid the graduated cylinder, the Erlenmeyer flask, or the beaker (7) ... 

Later, the SFA was developed to suit an even broader range of measurements, and in 1985 Israelachvili reported a set-up of the SFA with vibrating upper surface suited for viscosity measurements of liquids confined between the surfaces [37]. 

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