Freed

In principle, simulation teclmiques can be used, and Monte Carlo simulations of the primitive model of electrolyte solutions have appeared since the 1960s. Results for the osmotic coefficients are given for comparison in table A2.4.4 together with results from the MSA, PY and HNC approaches. The primitive model is clearly deficient for values of r. close to the closest distance of approach of the ions. Many years ago, Gurney [H] noted that when two ions are close enough together for their solvation sheaths to overlap, some solvent molecules become freed from ionic attraction and are effectively returned to the bulk [12]. 

Hwang L-P and Freed J H 1975 Dynamic effects of pair correlation functions on spin relaxation by translational diffusion in liquids J. Chem. Rhys. 63 4017-25... 

ELDOR has been employed to study a number of systems such as inorganic compounds, organic compounds, biologically important compounds and glasses. The potential of ELDOR for studying slow molecular motions has been recognized by Freed and coworkers [29, 30]. 

Multiple Electron Resonance Spectroscopy ed M M Doric and J H Freed (New York Plenum) ch 14, pp 475-507... 

Freed J H 1969 Theory of saturation and double resonance effects in ESR spectra. IV. Electron-nuclear triple resonance J. Chem. Rhys. 50 2271-2... 

Hyde J S, Chien J C W and Freed J 1968 Electron-electron double resonance of free radicals In solution J. Chem. Phys. 48 4211-26... 

Bruno G and Freed J 1974 ESR llneshapes and saturation In the slow motional region ELDOR Chem. Phys. Lett, pp 328-32... 

Budil D E, Earle K A, Lynch W B and Freed J H 1989 Electron paramagnetic resonance at 1 millimeter wavelengths Advanced EPR in Biology and Biochemistry ed A J Hoff (Amsterdam Elsevier) ch 8, pp 307 0... 

Earle K, Budll D and Freed J 1996 Millimeter wave electron spin resonance using quasloptical techniques Advances in Magnetic and Optical Resonance vol 19, ed W Warren (San Diego ... 

Because the number of grazing encounters is a fimction of the diflfiision coefficient, CIDEP by the RPM mechanism is a strong fiinction of the viscosity of the solvent and, in general, the RPM becomes stronger with increasing viscosity. Pedersen and Freed [39] have developed analytical teclmiques for the fiinctional fonn of the viscosity dependence of the RPM. 

Pedersen J B and Freed J H 1973 Theory of chemically induced dynamic electron polarization. I J. 

Freed K F 1987 Renormalization Group Theory of Macromolecules (New York Wiley-Interscience)... 

Foreman K W and Freed K F 1998 Lattioe oluster theory of multioomponent polymer systems ohain semiflexibility and speoifio interaotions Adv. Chem. Phys. 103 335... 

Karl F. Freed, The James Franck Institute, The University of Chicago, Chicago, Illinois, U.S.A. 

Aluminium is obtained on a large scale by the electrolysis of the oxide, dissolved in fused cryolite The oxide, occurring naturally as bauxite, AI2O3.2H2O, usually contains silica and iron(III) oxide as impurities. These must be removed first, since aluminium, once prepared, cannot be freed of other metals (which will be deposited on electrolysis) by refining it. The crude oxide is dissolved under pressure in caustic soda solution the aluminium oxide and silica dissolve and the ironflll) oxide is left ... 

Commercial preparations of acetyl chloride are best freed from volatile phos. phorus compounds and dissolved hydrogen chloride by redistillation from 5-10 per cent, of the volume of pure dimethylaniline. 

Acetylene is obtained from a cylinder (at ground level outside the fum chamber) and is freed from acetone by passing through two 500 ml. wash bottles, half filled with concentrated sulphuric acid, at the rate of 2-3 litres per minute when the acid in the second wash bottle becomes discoloured, the wash bottles should be recharged with fresh acid. The... 

This procedure may be used for the preparation of finely-divided sodamide If the sodamide is to be used in any other solvent than liquid ammonia, the ammonia is allowed to evaporate whilst the new solvent is slowly added from a dropping funnel alternatively, the new solvent may be added before the ammonia evaporates. If dry sodamide is required, the product may be freed from the last traces of ammonia by evacuation at 100°. The sodamide prepared by this method must be used immediately if allowed to stand, it rapidly changes into explosive substances. 

Note 1. The acetylene was freed from acetone by means of two traps, cooled at -75°C. 

After the air in the flask had been completely replaced with nitrogen, it was cooled in a liquid nitrogen bath and a solution of 25 g of acetylene in 160 ml of dry THF was introduced. The solution had been prepared by dissolving acetylene (freed from acetone by means of a cold trap) in THF cooled at -80 to -90°C. A solution of 0.21 mol of butyl lithium in about 150 ml of hexane was added in 5 min to the vigorously stirred solution. During this addition the temperature of the mixture was kept between -80 and -100°C by occasionally dipping the flask into the liquid nitrogen. To the white suspension were successively added at -80°C a solution of 10 g. of anhydrous lithium bromide (note 1) in 30 ml of THF and 0.20 mol of freshly distilled benzaldehyde. The reaction mixture was kept for 3 h at -69°C, after which the temperature was allowed to rise to +10°C over a period of 2 h. 

The nickel ion freed may then be determined by an EDTA titration. Note that two moles of silver are equivalent to one mole of nickel and thus to one mole of EDTA. 

Caustic Soda. Diaphragm cell caustic is commercially purified by the DH process or the ammonia extraction method offered by PPG and OxyTech (see Fig. 38), essentially involving Hquid—Hquid extraction to reduce the salt and sodium chlorate content (86). Thus 50% caustic comes in contact with ammonia in a countercurrent fashion at 60°C and up to 2500 kPa (25 atm) pressure, the Hquid NH absorbing salt, chlorate, carbonate, water, and some caustic. The overflow from the reactor is stripped of NH, which is then concentrated and returned to the extraction process. The product, about 62% NaOH and devoid of impurities, is stripped free of NH, which is concentrated and recirculated. MetaUic impurities can be reduced to low concentrations by electrolysis employing porous cathodes. The caustic is then freed of Fe, Ni, Pb, and Cu ions, which are deposited on the cathode. 

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