Subject insensitive

The criteria for insensitive explosives subjected to ha2ard tests permit no reaction more violent than burning in slow and fast cook-off tests and fragment and bullet tests, no propagation in sympathetic detonation tests, no detonation when stmck by a shaped charge jet, no sustained burning when hit by a small fragment, and such special tests as may be required by the use of the explosive. 

Rased on the above data, it would seem unusual if reactivity of the propagating species in copolymerization were insensitive to the nature of the last added monomer units. However, while there are ample experimental data to suggest that copolymerizations should be subject to penultimate unit effects that affect the rate and/or copolymer composition, the origin and magnitude of the effect is not always easily predictable. 

Returning now to the subject of the chapter, in addition to appropriate retentive characteristics, a potential stationary phase must have other key physical characteristics before it can be considered suitable for use in LC. It is extremely important that the stationary phase is completely insoluble (or virtually so) in all solvents that are likely to be used as a mobile phase. Furthermore, it must be insensitive to changes in pH and be capable of assuming the range of interactive characteristics that are necessary for the retention of all types of solutes. In addition, the material must be available as solid particles a few microns in diameter, so that it can be packed into a column and at the same time be mechanically strong enough to sustain bed pressures of 6,000 p.s.i. or more. It is clear that the need for versatile interactive characteristics, virtually universal solvent insolubility together with other critical physical characteristics severely restricts the choice of materials suitable for LC stationary phases. 

The Production Department was not amused, because lower values had been expected. Quality Control was blamed for using an insensitive, unse-lective, and imprecise test, and thereby unnecessarily frightening top management. This outcome had been anticipated, and a better method, namely polarography, was already being set up. The same samples were run, this time in duplicate, with much the same results. A relative confidence interval of 25% was assumed. Because of increased specificity, there were now less doubts as to the amounts of this particular heavy metal that were actually present. To rule out artifacts, the four samples were sent to outside laboratories to do repeat tests with different methods X-ray fluorescence (XRFi °) and inductively coupled plasma spectrometry (ICP). The confidence limits were determined to be 10% resp. 3%. Figure 4.23 summarizes the results. Because each method has its own specificity pattern, and is subject to intrinsic artifacts, a direct statistical comparison cannot be performed without first correcting the apparent concentrations in order to obtain presumably true... 

Rates of addition to carbonyls (or expulsion to regenerate a carbonyl) can be estimated by appropriate forms of Marcus Theory. " These reactions are often subject to general acid/base catalysis, so that it is commonly necessary to use Multidimensional Marcus Theory (MMT) - to allow for the variable importance of different proton transfer modes. This approach treats a concerted reaction as the result of several orthogonal processes, each of which has its own reaction coordinate and its own intrinsic barrier independent of the other coordinates. If an intrinsic barrier for the simple addition process is available then this is a satisfactory procedure. Intrinsic barriers are generally insensitive to the reactivity of the species, although for very reactive carbonyl compounds one finds that the intrinsic barrier becomes variable. ... 

Egawa et al. [103] by using a microbial assay method reported that miconazole was not detected in the blood after human subjects were given 100 mg tablets of miconazole intravaginally for 14 days. Six species of 12 strains of human vaginal Lactobacillus were insensitive to miconazole. 

Benzoyl peroxide appears to decompose entirely by the radical mechanism, the reaction being rather insensitive either to solvent changes or to the addition of acid catalysts. The unsymmetrical peroxide, -methoxy-/> -nitrobenzoyl peroxide, behaves quite differently. It will decompose either by the polar mechanism or by the radical mechanism.821 The radical mechanism prevails in benzene and the acids produced are -nitrobenzoic and anisic in equal amounts. In the more polar solvents anisic acid is formed to a lesser extent than is >-nitrobenzoic acid, because the carboxy inversion reaction (rearrangement) competes successfully. The reaction is subject to acid catalysis... 

Hake Effect. Some industrial explosives, even when made of normal consistency, are subject under certain conditions to a change in storage, by which they become very insensitive. Quinan (Ref) called this the Hake Effect in honor of C. Napier Hake, the late Inspector of Explosives for the State of Victoria, Australia... 

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