Chief feature

The present method is applicable with slight modifications to the preparation of both the ortho and para aminonaphthols and to many homologues, benzologues, and heterocyclic isologues of these substances. The chief feature of novelty is in the use of stannous chloride as an antioxidant in preparing and crystallizing the amine hydrochlorides. 

Recent developments in the practice of thin-layer chromatography have resulted in a breakthrough in performance which has led to the expression high performance thin-layer chromatography . These developments have not been the result of any specific advance in instrumentation (as with HPLC), but rather the culmination of improvements in the various operations involved in TLC. The three chief features of HPTLC are summarised below, but for a comprehensive account of the subject the reader is recommended to consult a more specialised text.59... 

The chief feature of anionic polymerizations in aprotic solvents is that they involve only two reactions initiation and propagation. Spontaneous transfer or termination reactions will not take place, if proper systems and adequate reaction conditions are chosen. 

Accessibility of the deposit to the insects by contact is the chief feature of the small vial method, but fumigant action cannot be eliminated entirely. In the case of DDT this has been found to be unimportant, for flies kept in the vials out of contact with the surface are not affected. But with 7-hexachlorocyclohexane or parathion there is a noticeable toxic effect. If the vials are stood upright, laid on the side, or hung upside down, there is a decrease in the mortality produced in the order given. The position on the side has been adopted because it avoids extremes and because practical use of an insecticide often involves limited but not accentuated ventilation. 

Despite the fact that overeating has troubled humankind for centuries, an eating disorder whose chief feature is binge eating was not formally recognized in the... 

It is a pretty town and perfectly civilized. By the way, in all American towns the electric car is the chief feature. There are overhead wires, and cars like our tram cars run at a prodigious rate, careless of life apparently, yet there are very few accidents. I suppose the fittest, i.e., those who don t get killed, survive. They are delightful as a form of motion and almost rival the bicycle. That creature, too, has penetrated everywhere, and is used even over the prairie (17). 

For this reason, a standard crucible test has been devised in which the chief features, compared with other tests, are the use of a leveled coal surface, a crucible of special shape and unidirectional heating by a gas flame. As a result, regularly shaped coke buttons are obtained and the degree of swelling is assessed by comparison with profiles of standard buttons. 

Early work on spermatogenesis has been reviewed in the first edition (796). More recent work has been reviewed by Euzet et al. (196), Davis Roberts (171), Ubelaker (889) and Lumsden Specian (462). Ultrastructure studies have shown that cestode spermatozoa generally (but see below) have the same pattern of organisation in all orders. The chief features are (a) a long thread-like body (b) an elongated nucleus (c) cortical microtubules underlying the plasma membrane (d) the absence of... 

Table 1 Summary of the most common metathesis catalysts and their chief features...

The chief feature of the mechanism of lipoamide dehydrogenase proposed by Massey and Veeger (15, 27) is the catalytic intermediate in... 

The chief feature of this test is that the rise in pressure of the gases is registered automatkally. This necessitates more complicated apparatus, and the practical application of the test has been very limited. 

A hydrolysis study (Ishiwatari, 1967a) showed the chief feature of infrared spectra of lake humic acid to be the presence of an absorption band at 1540 cm , probably arising from peptide bonds. No infrared evidence to show the aromatic structure of humic acid has been obtained. 

Let us now take into account a 2-D vertical dielectric slab that divides the computational domain into three regions two filled with air, namely s = . o for i < L and i > L2, and one with the dielectric e for L < i < L2, as shown in Figure 2.6(b). The chief feature of this material is that its permittivity is a piecewise constant function of x solely, with the points of material discontinuity restricted to coincide with electric field nodes. Across this dielectric interface, tangential components Ez and Hy are continuous, whereas all second-order and higher order derivatives of both fields are discontinuous. Thus, for Hy at L and L2, one may potentially use the fifth-order extrapolation of [26] based on data from the air regions,... 

Other reactions of hemoglobin also permit a free radical interpretation, notably the coupled oxidation with ascorbic acid by molecular 02 which yields choleglobin, but further discussion requires a full kinetic analysis. Even though the denaturation reactions described above have not been examined kinetically it is worth emphasizing that their chief features can be explained by the formation of 02- as in the mechanism advanced for the autoxidation. The liberation of an activated O2 molecule is no longer required—02 is the active oxygen. 

A multitude of electrochemical techniques based on electrode processes exist however, only a comparatively small number are of real importance to the analytical chemist. Some of the chief features of these techniques are shown in Table 1.1. 

Trans-tCHlv. the most extensively investigated conducting polymer, is representative, in a broad sense, of all those conducting polymers which are dopable by redox processes, 2. Its chief features will therefore be outlined below. 

The process which Straub employs to prepare hydrazo-compounds from nitro-hydrocarbons is yet to be mentioned. The chief feature of his experiments is that the original material and all intermediate products are retained in solution during the electrolysis by the selection of a suitable solvent, and the hydrazo-compounds are withdrawn from the action of the current by precipitation. 

The chief features of an instantaneous reaction have already been described in Chapter 14. However, in a liquid-liquid reaction with its two liquid films, the reaction plane can be located within either one of these films. Thus a criterion is needed for determining the phase in which it is located. Figure 15.5 illustrates a reaction in phase 2. Such a criterion has been derived by Scriven (1961) from the penetration theory and by Mhaskar and Sharma (1975) from the simpler film theory. The application of this criterion tells when the plane is located in phase 1, when in phase 2, and when at the interface of the two liquids. Table 15.1 gives this criterion along with the rate equations. 

A number of clinical manifestations seems to be common to both diseases fever, arthralgia, myalgia, pleuritis, pericarditis, skin rashes, and anemia. An analysis of patients with drug-induced lupus enables a number of generalizations to be drawn about the chief features of the disease. 

The chief feature is that the experimentally measured quantities become actually insensitive to the fine elements of the structure instead, they perceive just the scaled-enlarged pattern of the system s structure. Such a bridge between the theuretico-iiiatlieiiiatieal procedure of scaling the Hamiltonian (the renormalization group transformation) and an experimentally measured quantity offers considerable scope for studies on substances in their critical state. 

Dignam has treated a model of the oxide which he claimed to account for the chief features of the experimental results. The oxide was supposed to be built up of microcrystals—small volumes of molecular groupings approximating to crystalline oxide. The rate of jumping of tantalum ions between the units was supposed to limit the current and to be determined by the effective field, a cavity field, and hence by the dielectric polarization of the oxide. ... 

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