Density/viscosity differences

In contrast, various sensors are expected to respond in a predictable and controlled manner to such diverse parameters as temperature, pressure, velocity or acceleration of an object, intensity or wavelength of light or sound, rate of flow, density, viscosity, elasticity, and, perhaps most problematic, the concentration of any of millions of different chemical species. Furthermore, a sensor that responds selectively to only a single one of these parameters is often the goal, but the first attempt typically produces a device that responds to several of the other parameters as well. Interferences are the bane of sensors, which are often expected to function under, and be immune to, extremely difficult environmental conditions. 

Fig. 33. Variation of dimensionless radius with dimensionless time for compact carbon black particles suspended in silicone oil undergoing a simple shear flow. Top Data for initial radius Ho 1.7 mm for different viscosities and different shear rates, but with Fa = 0.28. Bottom Data for initial radius R0 = 2.0 mm for different densities and different shear rates, but with Fa 0.28. For all cases the erosion rate constant kc = 0.37. (See Eq. 53).

The liquid properties of primary importance are density, viscosity and surface tension. Unfortunately, there is no incontrovertible evidence for the effects of liquid viscosity and surface tension on droplet sizes, and in some cases the effects are conflicting. Gas density is generally considered to be the only thermophysical property of importance for the atomization of liquids in a gaseous medium. Gas density shows different influences in different atomization processes. For example, in a fan spray, or a swirl jet atomization process, an increase in the gas density can generally improve... 

This diversity in solvent properties results in large differences in the distribution ratios of extracted solutes. Some solvents, particularly those of class 3, readily react directly (due to their strong donor properties) with inorganic compounds and extract them without need for any additional extractant, while others (classes 4 and 5) do not dissolve salts without the aid of other extractants. These last are generally used as diluents for extractants, required for improving then-physical properties, such as density, viscosity, etc., or to bring solid extractants into solution in a liquid phase. The class 1 type of solvents are very soluble in water and are useless for extraction of metal species, although they may find use in separations in biochemical systems (see Chapter 9). 

The classical FEE retention equation (see Equation 12.11) does not apply to ThEEE since relevant physicochemical parameters—affecting both flow profile and analyte concentration distribution in the channel cross section—are temperature dependent and thus not constant in the channel cross-sectional area. Inside the channel, the flow of solvent carrier follows a distorted, parabolic flow profile because of the changing values of the carrier properties along the channel thickness (density, viscosity, and thermal conductivity). Under these conditions, the concentration profile differs from the exponential profile since the velocity profile is strongly distorted with respect to the parabolic profile. By taking into account these effects, the ThEEE retention equation (see Equation 12.11) becomes ... 

Our own investigations concentrated on compounds with different densities (PFO and perfluorohexyl-ethane) and additionally on compounds with comparable densities but different viscosities. Perfluorohexyl-ethane was tested as a monomer and in two oligomeric configurations with the same molecular unit but... 

Although most oils have similar surface tension and density, they differ greatly in viscosity. The viscosity, the output of liquid, the efficiency of the application of energy to the liquid, and the degree of evaporation after the particle is formed are important factors to utilize in producing the desired particle size. In heat vaporization aerosols the distillation range of the solution is also important. 

Zlokarnik M. Influence of density and viscosity differences on mixing time in the homogenisation of liquid mixtures (in German). Chem Ing Tech 1970 42 1009-1011. 

The objectives of using solvents are diverse, e.g., to dissolve a solid substrate, to limit catalyst deactivation, to improve selectivity, or to enhance mass-transport. The solvents are selected depending on the substrate and the desired effect. Hence, they range from water, alcohols, ethers, or low alkanes, to CO2. The effects of the solvent on phase-behaviour, viscosity, and density at different concentrations, temperatures and pressures can explain much about the effect of the solvent on the reaction. 

The properties of Ge(OR)4 allow them to be considered more likely to be the esters of an inorganic acid than metal alkoxides these are colorless volatile liquids, containing monomeric tetrahedral molecules. The solid crystalline form is known only for R = Bu, OC6Hnc, and also 2,6-substituted phenoxides. All the members of the Ge(OR)4 homologous series are characterized by thoroughly determined physical characteristics — density, refraction index, surface tension, viscosity (and calculated parachor values), dipole moments in different solvents [222, 857, 1537] (Table 12.9). The results of the investigation of vapor pressure, density, viscosity polytherms, and so on. permitted rectification for the preparation of samples of high purity for sol-gel and MOCVD applications [682, 884]. 

Supercritical water is a phase of water that exists above its critical temperature and pressure (647 K and 221 atm, respectively). This unique state of water has different density, viscosity, and ionic strength properties than water under ambient conditions. Because the solubility of organic... 

Hydrolytic and radiolytic degradation of TAP solution in normal paraffinic hydrocarbon (NPH) in the presence of nitric acid was investigated. Physicochemical properties such as density, viscosity, and phase-disengagement time (PDT) were measured for undegraded and degraded solutions (197). The variations in these parameters were not very different from those obtained with degraded TBP. Thus, the hydro-dynamic problems expected during the solvent-extraction process with TAP would be similar to those encountered with TBP/NPH system. The influence of chemical... 

For a material system with density and viscosity differences, the 5-parametric relevance list, eq. (5.1), has to be extended by the physical properties of the second mixing component, by the volume ratio of both phases, (p = V2/Vi, and - inevitably - by the weight difference, gAp, due to the prevailing density differences, to a 9-parametric dimensional space [15] ... 

The factors affecting the design of mechanically agitated liquid-liquid reactors are the miscibility of the liquid phases, the interfacial tension, and the densities and viscosities of the liquid phases, as well as the density and viscosity differences between the two liquids. As shown in Fig. 21, a variety of stirrer configurations are available to carry out liquid-liquid reactions. 

Once the topology has been established, it must be supplemented with the flows of the currents, which convey between the cells. Many solutions have been suggested to solve this problem. They differ by the mode of calculation of the main current produced by the stirrer. It is a function of the geometry, the number of the turns of the stirrer and the properties of the medium (density, viscosity). For the stirrer considered here, the flow rate of the main current and the flows in the higher and lower regions are calculated with the assistance of relations (4.4) and (4.5). Here f (p, Tj) expresses a function depending on the density and viscosity of the mixed medium ... 

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