Saturation Method

Relationships connecting stmcture and properties of primary alkylamines of normal stmcture C, -C gin chloroform and other solvents with their ability to extract Rh(III) and Ru(III) HCA from chloride solutions have been studied. The out-sphere mechanism of extraction and composition of extracted associates has been ascertained by UV-VIS-, IR-, and H-NMR spectroscopy, saturation method, and analysis of organic phase. Tertiary alkylamines i.e. tri-n-octylamine, tribenzylamine do not extract Ru(III) and Rh(III) HCA. The decrease of radical volume of tertiary alkylamines by changing of two alkyl radicals to methyl make it possible to diminish steric effects and to use tertiary alkylamines with different radicals such as dimethyl-n-dodecylamine which has not been used previously for the extraction of Rh(III), Ru(III) HCA with localized charge. 

Westcott, J. W., Simon, J. J., Bidleman, T. F. (1981) Determination of polychlorinated biphenyl vapor pressures by a semimicro gas saturation method. Environ. Sci. Technol. 15, 1375-1378. 

Akiyoshi, M., Deguchi, T., Sanemasa, I. (1987) The vapor saturation method for preparing aqueous solutions of solid aromatic hydrocarbons. Bull. Chem. Soc. Jpn. 60, 3935-3939. 

Sato, N., Inomata, H., Arai, K., Saito, S. (1986) Measurements of vapor pressures for coal-related aromatic compounds by gas saturation method. J. Chem. Eng. Jpn. 19, 145-147. 

Wania, F., Shiu, W.-Y., Mackay, D. (1994) Measurement of the vapor pressure of several low-volatility organochlorine chemicals at low temperatures with a gas saturation method. J. Chem. Eng. Data 39, 572-577. 

Most agricultural pyrethroids have a very low vapor pressure (Vp) - around 10 8 mmHg at an ambient temperature - which is usually measured by the gas saturation method [8] and, therefore, its distribution to an air compartment is considered less important, as listed in Table 1. Tsuzuki [27] has improved the modified Watson method to estimate the vapor pressure of pyrethroids with reasonable precision just from their chemical structures. The volatilization from water can be conveniently evaluated by the Henry s law constant defined as vapor pressure divided by water solubility [28] and the small values of synthetic pyrethroids... 

Starting from the observations that HpHb has a much higher peroxidase activity at acid pH and is more resistant to I2 than Hb, Jayle (J5) devised two similar methods for measuring Hp—the activation and the saturation methods—which are still in common use. The difference between the electrophoretic mobility of HpHb and of Hb was also later (L10) utilized to estimate the serum Hp concentration. The general agreement between results obtained by both methods was shown by Nyman (N5). 

Pulse schemes similar to that of the offset-saturation method, often with a homospoil gradient pulse to destroy any x-y magnetization, have been utilized in off-resonance Tip experiments to study intermediate molecular motions in biological systems [107-111] and inorganic compounds [112] from... 

A plot of the 2 magnetization (M /Moo) as a function of the irradiation resonance offset is given for an offset saturation experiment on a sample of degassed cyclohexane (CeHn) in CDCI3 at a temperature of 303 K. At this temperature, the cyclohexane resonance was noticeably narrow at 280 K, the linewidth of the cyclohexane resonance was approximately 1.2 Hz, compared to a width of 0.5 Hz for the internal TMS standard. From the resulting values of T and T2, and the measured low-temperature axial-equatorial chemical shift difference of 45.4 Hz at 100 MHz used in eq. (22), the rate at 293 K was determined to be 1.94 x 10 s Thus, rates on the order of 10 or 10 s are accessible in relatively simple systems using the offset-saturation method. 

Water saturation method. More recently, a method has been described by Quinn and Paton (16), who claim that their procedure more closely simulates actual food production applications than does the excess water method. In this technique, only enough water, essentially all of which is retained upon centrifugation, is added to saturate the sample. A comparison of the excess water method and the proposed method for various protein products, as reported by Quinn and Paton, is presented in Table IV. 

The system Nd(I03)3-MI03-H20 (M = K, Rb) were studied by the isothermal saturation method, and 3Nd(I03)3-2KI03-2H20 was described and studied by TGA and IR.247... 

Wania et al. (1994) used commercial lindane and a gas saturation method, and they obtained for the temperature range between -30° and +30°C ... 

The most popular method used is a dynamic method, the saturation method. In this technique, the non-volatile, heavy solid solute is loaded into a saturator, or a battery of two or more saturators connected in series, and remains there as a stationary phase during the experiment. In most cases the saturator is in the form of a packed column. At constant pressure, a steady stream of supercritical fluid (solvent) passes through a preheater, where it reaches the desired system temperature. Then this fluid is continuously fed to the bottom of the saturator, and the solute is stripped from the stationary heavy phase in the column. The supercritical fluid saturated with the solute leaves the saturator at the top. 

Fig. 11. Cation exchange capacity (NH saturation method) in the Gironde and Loire estuaries.

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