Group parameters

In principle, mineral oil (see also Chapter 6) is also a group parameter. All compounds that are extracted, are not removed during clean-up, pass the chromatographic column and are detected by the universal detector are said to be mineral oil. The influence on changing parameters of the method will not be as significant as with the EOX-determination. All mineral oil compounds are very non-polar. Hence care has to be taken. 

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Group number Group parameter tar yield, % Code number ... 

Oleksy-Frenzel J, Wischnack S, Jekel M (2000) Application of ion-chromatography for the determination of the organic-group parameters AOCl, AOBr and AOI in water. Fresenius J Anal Chem 366 89-94... 

De Gaetano A, Mingrone G, Castagneto M. NONMEM improves group parameter estimation for the minimal model of glucose kinetics. Am J Physiol 1996 271 E932-7. 

Mi A Zagreb group parameter = sum of square of degrees over all vertices... 

In principle, the empirical group parameter methods can be used to aid molecular structure determination, but their principal use to date has been in the determination of the nature of bonding and the electron distribution in compounds by interpretation of the magnitudes of the empirically evaluated parameters. 

This book contains a small database for organic and inorganic compounds. Its main value, however, is that it describes a group additivity scheme to estimate thermochemical data. An updated and extended list of group parameters is given in NIST Therm [28]. The first edition of this classic work is from 1968. 

Note that a similar correlation did not have to be developed for the PFGC-MES equation of state. Adequate data were available to develop (or estimate) group parameters for all the molecules considered in this work. TTie predicted water solubilities of the higher molecular weight components appear to be reasonable, but no data are available to check the quality of the predictions. 

The preceding prediction rules are largely restricted to acyclic compounds. But there is also a considerable need for parameter sets enabling the spectroscopist to calculate I3C chemical shifts of conformationally defined cyclic molecules, especially of the cyclohexane type. Methyl-group effects in methylcyclohexanes (100,101) that are to be added to the basic value for cyclohexane itself (8 = 27.3) are listed in Table 29. Analogous methyl-group parameters in tetralins and tetra-hydroanthracenes have been reported (403). 

Species/strain Doses employed Route of administration Study design Number/sex/group Parameters and endpoints evaluated Results Mortality Clinical signs Body weights... 

Piet, G. J. Wegman, R. C. C. Quaghebeur, D. Guidelines for the Application of Organic Group Parameters and Determination of Phenols in the Environment Environment Research Programme. Report OMP/37/83 Commission of the European Communities Brussels, 1983.. ... 

CONTRIBUTION VALUES TO LOG S OF GROUP PARAMETERS IN MODELS OF KLOPMAN, WANG, AND BALTHASAR [1]... 

The parameter B2 is chosen for this project in order to gain some insight into possible consequences of varying the capability of the acetylcholinesterase to hydrolyze the neurotransmitter. Imbalances in this capability give rise to devastating diseases such as Alzheimer s and Parkinson s. The enzyme activity is included in the grouped parameter B2, which includes the maximum reaction velocity in reaction 2. The parameter B2 itself includes the enzyme activity together with three constants for the enzyme system, namely the concentration of acetylcholinesterase in compartment (II), the volume V2 of compartment (II), and the flow rate q. 

Group Number Alternative Group Parameters Sub- group Number Alternative Subgroup Parameters ... 

All GCMs suffer from two major problems of principle. First, they can only handle molecules and mixtures for which all required group parameters or group-interaction parameters have been fitted before. This limitation is more severe for the two-dimensional methods because parameters for all combinations of groups have to be available. This is more unlikely than just... 

Binde, F. and H.H. Riittinger. 1997. Isolation and determination of dissolved organic sulfur compounds— development of the organic group parameter DOS. Fresenius J. Anal. Chem. 357 411—415. 

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