Of solvents, table

The model has the advantage that it requires only a simple table eontaining the polarity index P and selectivity group for a number of solvents (Table 4.2). The model is based on Snyder s elassifieation of solvents [41,42] aeeording to their eharaeteristies to internet as proton aeeeptors (xj, proton donors (x, or dipoles (xj. 

Selection of Solvents. The extraction yield of a low rank coal (Annesley) has been determined after digestion using a selection of solvents (Table II). The results show large variations in solvent power and, in particular, the high extraction yields obtained with hydrogen donor solvents. It is important to differentiate between the ability of a solvent to prevent polymerisation of the dissolved coal by hydrogen transfer, and its ability to retain the dissolved coal in solution. For example, Tetralin is frequently quoted as an... 

Physical properties. The specific gravity of the substance is 1.508. It is sparingly soluble in water. Simecek and Dolezel [82] report the following figures for its solubility, expressed as the amount in grammes dissolved per 100 g of solvent (Table 22) ... 

The recently published solubility data of Roberts and Dinger [14] agree well with those reported by T. Urbanski and Kwiatkowski. The differences are only apparent, owing to the fact that the solubility is reported by the latter authors as grammes of pentaerythritol tetranitrate dissolved in 100 g of solvent (Table 31). 

The stability constants for AgXj species (where X = Cl-, Br- or I-) have been determined for a range of solvents (Table 50).363"363 The table shows that in all cases higher stability was found in a non-aqueous solvent than occurred in water. 

The optical activity of poly-vinyl-ethers, in the few cases investigated (22), does not appear to be dependent on the concentration of the solution, but it changes remarkably depending on the type of solvent (Table 14). 

The solubility of atorvastatin calcium, Form-I, was measured in a variety of solvents (Table 1.2) by taking an excess of atorvastatin calcium in screw-capped vials with 10 ml of the solvent, followed by analysis of the dissolved fraction after 24 h by high-performance liquid chromatography (HPLC). The pH of a saturated solution of atorvastatin calcium in water was found to be 7.12 (Fig. 1.16). 

Oligopeptides with tendencies to adopt a-helical or unordered structures showed no pronounced change in solubility or coupling kinetics during chain elongation in the LPM as exemplified in the case of the oligomethionines181). For example, the oligomethionine, L-(Met)15-NH-PEG exhibits excellent solubility in a number of solvents (Table 5). 

The strong influence of solvent (Table 20) and crown ether (Table 21) on the net... 

If the concentration is reckoned in mols. per kilo, (according to Raoult) instead of in mols. per litre (according to Arrhenius), then L is the latent heat of 1 kilo, of solvent. Table A contains a selection from the available experimental data in confirmation of this law (Landolt and Bomstein, 3rd edition). 

Some typical results are shown in Figure 16.2 (LLE for PS/acetone), Table 16.4 (infinite dilution activity coefficient for PBMA solutions in a variety of solvents). Tables 16.5 and 16.6 (activity coefficients of low- and heavy-molecular-weight alkanes in asymmetric athermal-alkane solutions). Table 16.7 (VLB for ternary polymer-solvent solutions). Figure 16.6 (VLB calculations for systems containing the commercial epoxy resin Araldit), and Table 16.8 (comparison of LLE results from various thermodynamic models). 

The above procedure presupposes that the MHS constants. Kg, a, Kx, and Ux are known. Values of Kg and Ug are available in the literature for a variety of solvents (Table 4.3), and so, in many cases are values of Kx and Ox- However, if the desired MHS constants are not available for the polymer under study in the GPC solvent or for the standard in the solvent to be used, they can be easily determined by measurement of the intrinsic viscosity, as described earlier. 

Bamford and Brumby2 measured individual rate constants in the polymerization of methyl methacrylate in several aromatic solvents, indicating that kp and kt varied with the type of solvents (Table 1). The kt value is approximately inversely proportional to the viscosity of the polymerization system, while a solvent effect was observed in kp in various aromatic solvents. They interpreted the solvent effect on kp in terms of the complex formation proposed by Henrici-Olive et al.67-71. ... 

A study of solvents (Table 3) shows that dichloromethane associated with ether (10/1) gives acceptable yields, but benzene, not acylated in these conditions, and nitromethane give better yields. BiCl3 is soluble in these last two solvents, at room temperature in MeN02, and the reaction proceeds in homogeneous conditions. 

From the effect of solvent (Table 15) it is evident that the reactions discussed are nitrene reactions hydrogen-rich solvents suppress ring contraction and give rise to solvent dimer (bibenzyl) and/or a yellow nitrene dimer. The structure of the dimer is not known, but one possibility is shown in 144. A similar (colorless) dimer was obtained from 9-phenanthridylnitrene at 500 ° 7). Xhe two dimers formed from 137 and 141 in cyclohexane have nearly identical IR spectra. How could a hydrogen-rich solvent promote dimeriztion There is evidence from aryl azide decomposition in solution that amino radicals are formed first, and these dimerize and dehydrogenate as shown for 1-naphthylnitrene in [Eq. (48)] 82). 

The proton chemical shifts of the a-hydrogens of tellurophene are strongly influenced by the polarity of solvent (Table IX), whereas only small differences are observed for the /1-protons. Aromatic solvents (C6D6, C6F6) induce an upfleld shift in both protons this effect has been employed in the determination of the direction of the dipole moment10 (see Section II,B,2). 

This procedure is not optimal. For the 60 g campaign, we required some 20 m of solvent (Table 8) and at the time of writing, we still have to work out the process for the 500 g production run, but they will probably not be significantly different from those described above. For larger scale processes, i.e. > 2 kg of reaction mixture, one would require oceans of solvent, and indeed for any production quantities (>10 kg discodermolide) an entire planet full Thus this process, while it works, still needs intensive optimization. 

A summary of the properties of polymers prepared chemically and electrochemically is shown in Table 3. The sizable differences in the ultraviolet absorption maxima is only apparent as the electrochemically polymerised samples were recorded as thin films on ITO glass whilst the chemically polymerised samples were recorded as solutions in NMP. Such hypsochromic changes in nre expected in going from the solid to solution phases and were borne out in model studies Although the conductivities of the polymers were of the order of 10 2 S cm-, these polymers were found to be soluble in a number of solvents (Table 4) in contrast to the total lack of solubility of polythiophene. 

Figure 2.4 (Klotz and Russo, 1966) illustrates the variation of degree of hydrogen bonding with solute concentration for a number of solvents Table 2.3 summarizes...

A large portion of all pharmaceuticals is obtained from nonwater solutions. The solvent is either a single component solvent (i.e ethanol, methanol, acetone, etc.) however it is often a mixture of solvents. Table 33.7, containing some information selected from Pakowski [9], presents exemplary drugs with moisture that is a solvent mixture. 

It is likely that the ASIS effect originates in the short-lived clustering of aromatic molecules around the terminus of the solute through dipole-induced dipole (or eventually C.T.) interactions (86). These effects would be superimposed onto any normal R. F. effects. Abraham (157) has determined the chemical shifts of the proton signal of methyl iodide in a number of solvents (Table 28), and introduced the concept of excess high field shift (EHS). The EHS is defined as the difference between the chemical shifts in aromatic and aliphatic solvents of similar structure. 

The solvents to be removed from the waste water may represent an asset or liability. Except in the case of the steam stripping of methanol and acetone, it is unlikely that the solvents arising from water clean-up will be fit for reuse. Further refining is usually necessary unless the treatment is close to the point source and therefore as free as possible from adventitious contamination. In the worst case, such as the cleaning of ground water contaminated with a variety of solvents (Table 3.7), it maybe necessary to... 

Classes of Solvents. Table 8.6 lists a number of solvents in which nucleophilic substitutions are carried out and classifies them according to two criteria whether they are protic or aprotic, and polar or nonpolar. 

Standard specifications are designed to set criteria for commercial solvents which can be used to determine the compliance of a solvent sample. Because applications of solvents differ very widely, the selected criteria are also different for different groups of solvents. Table 15.1.1 is a compiled list of parameters all of which can be found in solvent specifications. The most common parameters used to characterize solvent include acidity, appearance, color, concentration of main component, distillation range, dry point, initial boiling point, and specific gravity. The methods of determining these parameters are found in fliis chapter. 

DIRECTORY OF SOLVENTS Table 6.2 Ozone depletion potentials... 

DIRECTORY OF SOLVENTS Table 7.2 List of Restrictive Classes in ADR... 

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