Liquid simple

Hansen J P and McDonald I 1976 Theories of Simple Liquids (New York Academic)... 

Mansoori G A and Canfield F B 1969 Variational approach to the equilibrium properties of simple liquids I J. Chem. Phys. 51 4958... 

Weeks J, Chandler D and Anderson H C 1971 Role of repulsive forces in determining the equilibrium structure of simple liquids J. Chem. Phys. 54 5237... 

Jarzeba W, Walker G C, Johnson A E and Barbara P F 1991 Nonexponential solvation dynamics of simple liquids and mixtures Chem. Phys. 152 57-68... 

Wood W W 1968 Monte Carlo studies of simple liquid models Physics of Simple Liquids ed H N V Temperley, J S Rowlinson and G S Rushbrooke (Amsterdam North Holland) chapter 5, pp 115-230... 

At equilibrium, in order to achieve equality of chemical potentials, not only tire colloid but also tire polymer concentrations in tire different phases are different. We focus here on a theory tliat allows for tliis polymer partitioning [99]. Predictions for two polymer/colloid size ratios are shown in figure C2.6.10. A liquid phase is predicted to occur only when tire range of attractions is not too small compared to tire particle size, 5/a > 0.3. Under tliese conditions a phase behaviour is obtained tliat is similar to tliat of simple liquids, such as argon. Because of tire polymer partitioning, however, tliere is a tliree-phase triangle (ratlier tlian a triple point). For smaller polymer (narrower attractions), tire gas-liquid transition becomes metastable witli respect to tire fluid-crystal transition. These predictions were confinned experimentally [100]. The phase boundaries were predicted semi-quantitatively. 

Another important breaktlirough occurred with the 1974 development by Laubereau et al [24] of tunable ultrafast IR pulse generation. IR excitation is more selective and reliable than SRS, and IR can be used in pump-probe experiments or combined with anti-Stokes Raman probing (IR-Raman method) [16] Ultrashort IR pulses have been used to study simple liquids and solids, complex liquids, glasses, polymers and even biological systems. 

Chandler D 1987. Introduction to Modem Statistical Mechanics. New York, Oxford University Press. Hansen J P and I R McDonald 1976. Theory of Simple Liquids. London, Academic Press. 

Rao M and B J Berne 1979. On the Force Bias Monte Carlo Simulation of Simple Liquids. Journal Chemical Physics 71 129-132. 

In a simple liquid-liquid extraction the solute is partitioned between two immiscible phases. In most cases one of the phases is aqueous, and the other phase is an organic solvent such as diethyl ether or chloroform. Because the phases are immiscible, they form two layers, with the denser phase on the bottom. The solute is initially present in one phase, but after extraction it is present in both phases. The efficiency of a liquid-liquid extraction is determined by the equilibrium constant for the solute s partitioning between the two phases. Extraction efficiency is also influenced by any secondary reactions involving the solute. Examples of secondary reactions include acid-base and complexation equilibria. 

Scheme for a simple liquid-liquid extraction without any secondary reactions. 

Example 7.14 shows how equation 7.24 is used to calculate the efficiency of a simple liquid-liquid extraction. 

For a simple liquid-liquid extraction, the distribution ratio, D, and the partition coefficient, Kd, are identical. 

Furthermore, the extent to which we can effect a separation depends on the distribution ratio of each species in the sample. To separate an analyte from its matrix, its distribution ratio must be significantly greater than that for all other components in the matrix. When the analyte s distribution ratio is similar to that of another species, then a separation becomes impossible. For example, let s assume that an analyte. A, and a matrix interferent, I, have distribution ratios of 5 and 0.5, respectively. In an attempt to separate the analyte from its matrix, a simple liquid-liquid extraction is carried out using equal volumes of sample and a suitable extraction solvent. Following the treatment outlined in Chapter 7, it is easy to show that a single extraction removes approximately 83% of the analyte and 33% of the interferent. Although it is possible to remove 99% of A with three extractions, 70% of I is also removed. In fact, there is no practical combination of number of extractions or volume ratio of sample and extracting phases that produce an acceptable separation of the analyte and interferent by a simple liquid-liquid extraction. 

A simple liquid-liquid extraction rarely extracts 100% of the analyte. How does this method account for incomplete extractions ... 

Let s assume that the solute to be separated is present in an aqueous phase of 1 M HCl and that the organic phase is benzene. Because benzene has the smaller density, it is the upper phase, and 1 M HCl is the lower phase. To begin the countercurrent extraction the aqueous sample containing the solute is placed in tube 0 along with a portion of benzene. As shown in figure A6.1a, initially all the solute is present in phase Lq. After extracting (figure A6.1b), a fraction p of the solute is present in phase Uq, and a fraction q is in phase Lq. This completes step 0 of the countercurrent extraction. Thus far there is no difference between a simple liquid-liquid extraction and a countercurrent extraction. 

Calibration of Gauges Simple liquid-column manometers... 

JP Hansen, IR McDonald. Theory of Simple Liquids, 2nd ed. London Academic Press, 1986. 

It is assumed that the liquid wets the plates and that the molecular layer of liquid adjacent to the top plate moves at the same velocity as the plate whilst the layer adjacent to the stationary plate is also stationary. Intermediate layers of liquid move at intermediate velocities as indicated by the arrows in the diagram. The term shear rate is defined as the rate of change of velocity with cross-section (viz. d /dr) and is commonly given the symbol ("y). It is not altogether surprising that with many simple liquids if the shear stresses are doubled then the shear rates are doubled so that a linear relationship of the form... 

J. Klein, E. Kumacheva. Simple liquids confined to molecularly thin layers. I. Confinement-induced liquid-to-solid phase transitions. J Chem Phys 705 6996-7009, 1998. 

W. W. Wood. Monte Carlo studies. In H.N.V Temperley, G. S. Rushbrooke, J. S. Rowlinson, eds. Physics of Simple Liquids. Amsterdam North Holland, 1968, pp. 116-230. 

J. D. Weeks, D. Chandler, H. C. Andersen. Role of repulsive forces in determining the equilibrium structure of simple liquids. J Chem Phys 54 5237, 1971. R. L. Rowley, M. W. Schuck, J. Perry. A direct method for determination of chemical potential with molecular dynamics simulations. 2. Mixtures. Mol Phys 55 125, 1995. 

To make evaluations more definite, we use optical and microwave experimental data, as well as calculations of molecular dynamics of certain simple liquids which usually fit the experiment. Rotation is everywhere considered as classical, and the objects are two-atomic and spherical molecules, as well as hard ellipsoids. 

Hiwatari Y. The applicability of the soft core model of fluids to dynamical properties of simple liquids, Progr. Theor. Phys. 53, 915-28 (1975). 

Hansen J. P., McDonald I. R. The Theory of Simple Liquids (Academic Press, London) (1986). 

Bonamy L., Nguyen Minh Hoang P. Far infrared absorption of diatomic polar molecules in simple liquids and statistical properties of the interactions. I. Spectral theory, J. Chem. Phys. 67, 4423-30 (1977) ... 

In addition to these relatively simple liquid phase aqueous systems, it is necessary to identify situations in which any of these aqueous phase reservoirs come into physical and chemical contact with solid surfaces (e.g., rocks, biomass, sediments, soils, magma etc.). In general, the presence of two or more phases (liquid plus one or more solid phase) provides important constraints on the chemical reactions that may occur within the system as a whole. 

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