ARAES characteristics

It should be noted that riobeit s Law is valid only for non-porous powders which deflagrate but do not expld. Hence, it is Inapplicable to powders which are porous such as BlkPdr, non-gelatinized, compressed NC, etc. See Burning and Burning Characteristics of Propellants for Artillery Weapons and Small Arms in Vol 2, B346-L to B347-L Refs 1) Marshall 1 (1917), 310-11 2) Perez Ara (1945), 417—18 3) S. Fordham,... 

The cytotoxic activities of the 2, 2 -difluoro analog (775) of 737 against Chinese hamster ovary and tumor cells, in comparison with those of 1- -d-arabinofuranosylcytosine ara-C, a drug for leukemia), have been studied 775 is transported the faster through membrane into cells, more effectively phosphorylated by the deoxycytidine kinase (to the 5 -mono-phosphate) and, after conversion into the 5 -triphosphate, more highly accumulated in the cells, with longer duration time, than is ara-C, but nevertheless 775 is incorporated into the DNA to a lesser extent than is ara-C. These characteristics of 775 were discussed. 

An investigation of the spectral and kinetic characteristics of radical cations of para-halogeno-A,A-dimethylanilines and / ara-halogenodiphenylamines in water/terr-butyl alcohol has been performed in view of the fact that such species are probable intermediates in photonucleophilic substitution of halogen638. Bathochromic shifts in the absorption maxima of the radical cations were observed in the order H=F < Cl < Br. The disappearance of the radical cations obeys second-order kinetics and the rate constants are close to the diffusion-controlled values. The radical cations arise from the singlet excited states of the halogenoarylamines and homolysis of the carbon-halogen bond competes with their formation. 

Cytidine deaminase had been reported to vary greatly among mammalian species, both in its kinetic characteristics and in its dominant location (17). In humans, the highest levels (pg ARA-C/min-g) were found in the liver with smaller amounts in the kidney and heart. By comparison, the highest levels in the mouse were found in the kidney, while the dog had very low enzyme activities and the monkey... 

The toxicity of cytarabine is dose dependent. The most characteristic toxicity of high-dose ara-C (HDAC >1 g/m per dose) regimens is a cerebellar syndrome of dysarthria, nystagmus, and ataxia. Risk of CNS toxicity is strongly correlated with advanced age and renal dysfunction. Renal insufficiency permits accumulation... 

From Table 4.2., it may be observed that both amino and alkoxy functions are regarded as electron donors by virtue of their resonance characteristic and, therefore, increase the dipolar i.e., ionic) nature of the carbonyl (C = 0) moiety. Further, ara-substituents do exert a marked and pronounced electron-withdrawing effect in the carbonyl function having more double-bond character and ultimately resulting in less intense local anaesthetic activity. 

Multiple regression on o/ and o/f-type parameters employs the dual substituent-parameter equation, which may be written as in equation 8. (The combining of the k and terms implies that there is no intercept term allowed, and k is now the actual value for the parent syston, cf below.) For any given reaction series the equation is appUed to meta- and / ara-substituents separately, and so values of p/ and pR characteristic both of reaction and of substituent position are obtained. The various type scales are linearly related to each other only approximately. In any given application the scale which gives the best correlation must be found . ... 

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