Groups experimental

Strauss and Williamst have studied coil dimensions of derivatives of poly(4-vinylpyridine) by light-scattering and viscosity measurements. The derivatives studied were poly(pyridinium) ions quaternized y% with n-dodecyl groups and (1 - y)% with ethyl groups. Experimental coil dimensions extrapolated to 0 conditions and expressed relative to the length of a freely rotating repeat unit are presented here for the molecules in two different environments ... 

The symmetry assignment of vibrational states refers to C3V point group. Experimental geometries and wave numbers are taken from [28,29] for CH3 and [30] for CF3. EPR parameters are taken from [31] forCH3 at %K and [32] forCF3..at77K. 

Fig. 6.6. Comparison of experiment and simulation for the same case as above (Fig. 6.5), but now for a system with deuterated methyl groups (experimental data from [185]... 

The difference between the mean of the data group (experimental or control) and the grand mean of the data... 

The spin-Hamiltonian of Equation (31) can also be used to describe EPR data (1 5, HO) of ions of the palladium and platinum transition groups, the rare earths, and the trans-uranic group. Experimental data, however, are not presently as plentiful for these elements as for those of the iron group. 

In 1976 he was appointed to Associate Professor for Technical Chemistry at the University Hannover. His research group experimentally investigated the interrelation of adsorption, transfer processes and chemical reaction in bubble columns by means of various model reactions a) the formation of tertiary-butanol from isobutene in the presence of sulphuric acid as a catalyst b) the absorption and interphase mass transfer of CO2 in the presence and absence of the enzyme carboanhydrase c) chlorination of toluene d) Fischer-Tropsch synthesis. Based on these data, the processes were mathematically modelled Fluid dynamic properties in Fischer-Tropsch Slurry Reactors were evaluated and mass transfer limitation of the process was proved. In addition, the solubiHties of oxygen and CO2 in various aqueous solutions and those of chlorine in benzene and toluene were determined. Within the framework of development of a process for reconditioning of nuclear fuel wastes the kinetics of the denitration of efQuents with formic acid was investigated. 

The Giese reaction has been used for reductive cyclization of a,/l-enones containing an isolated terminal double bond. Solvomercuration can be carried out selectively on the latter group. On hydride reduction, the mercurial group is reduced preferentially and undergoes addition to the enone group. Experimentally, no products resulting from prior reduction of the enone are observed. Yields of cyclized products are usually satisfactory.4... 

Alkenes and metal hydrides experimental studies 66 Alkenes and metal hydrides theoretical studies 67 Elimination of metal hydrides from organometallics 68 Complex metal hydrides and polar functional groups experimental studies 69... 

COMPLEX METAL HYDRIDES AND POLAR FUNCTIONAL GROUPS EXPERIMENTAL STUDIES... 

Wu, Y.-D. Tucker, J. A. Houk, K. N. Stereoselectivities of nucleophilic additions to cyclohexanones substituted by polar groups. Experimental investigation of reductions of trans-decalones and theoretical studies of cyclohexanone reductions. The influence of remote electrostatic effects, J. Am. Chem. Soc. 1991,113, 5018-5027. 

The CO of Ihe acetyl ligand has a choice of four cis positions into which it may shift, displacing the CO that is already there. One of these sites is occupied by CO. Thus we would predict that 25% of the product would have no CO and the other 75% would have a CO ligand cis to the methyl group. Experimentally it is found that 25% of the product is devoid of tagged CO. 25% of the product has CO Irans to CH. and 50% of the product has CO cis to CH,. Therefore CO insertion must be eliminated as a mechanistic possibility, a methyl migration mechanism, however. i.s consistent with these experimental results. 

Figure 3. ESR spectrum of the 2-ethylidene-l,3-dioxolan radical cation center indicated by a triangle. The radical cation has large CH3 splittings note, e.g., the well resolved second-order components. The size of the CH3 coupling, 2.511 mT, indicates that the unpaired spin resides mainly on the carbon atom next to the CH3 group. Experimental conditions photolytic flow system, aqueous solutions of pH 5 at 3°C containing 0.3 m acetone, 0.02 m K2S2O8, and 0.03 m 2-(l-bromoethyl)-1,3-dioxolan. From Ref. [79].

Blocking is used to increase the power of an experiment by removing known sources of variability from the estimate of error. Blocks can include panelists, replications, treatment, or anything else that is a known source of variation. By grouping experimental units into blocks, a more accurate measure of pure or experimental error is obtained. 

MacPhee, J.A., Panaye, A. and Dubois, J.-E. (1978a). Operational Definition of the Taft Steric Parameter. An Homogeneous Scale for Alkyl groups - Experimental Extension to Highly Hindered Groups. Tetrahedron Lett., 34, 3293-3296. 

Several research groups experimentally and theoretically reported the enhancement in mass transfer in membrane separation processes using Dean vortices, and their findings are summarized in Tables 1 and 2. 

Figure 4. C(ls) binding energy shifts for selected functional groups. Experimental, (-----------------------------) calculated.

Many drugs of therapeutic importance, e.g., hexafluorenium, pancuronium (S9, SIO), and succinylcholine itself, are bis quaternary ammonium complexes which are reversible inhibitors of cholinesterase. One of the charged groups occupies the anionic site, but there is uncertainty regarding the attachment of the second quaternary nitrogen group. Experimental evidence shows that the bis quaternary compoimds are more than twice as potent (mole for mole) as inhibitors of cholinesterase than are simple quaternary ammonium compounds (M4). 

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