Primary parent

Phenol radical cations exist only in strong acidic solutions (pKa -1) [1, 2]. However, in non-polar media phenol radical cations with lifetimes up to some hundred nanoseconds were obtained by pulse radiolysis [3], The free electron transfer from phenols (ArOH) to primary parent solvent radical cations (RX +) (1) resulted in the parallel and synchroneous generation of phenol radical cations as well as phenoxyl radicals in equal amounts, caused by an extremely rapid electron jump in the time scale of molecule oscillations since the rotation of the hydroxyl groups around the C - OH is strongly connected with pulsations in the electron distribution of the highest molecular orbitals [4-6]. 

The neptunium (4n + 1) series is now extinct on Earth. This is due to the reiativeiy short haif-iife of the primary parent Np (Ti/2 = 2.14 x 10 a, which is iess than the age of the human race). The nearly 2,136 half-lives, that have elapsed since the creation of our planet (about 4.57 x 10 years ago], have practically wiped out this process because only 1 out of 10 neptunium-237 atoms is expected to survive. Now, the odds of survival are really bad, considering that 10 Np atoms would "weigh" about 3 x 10 kg, whereas the mass of the Sun is a mere 2 x 10 ° kg, and even that of the Milky Way is only estimated to about 2 x 10 kg... 

Chains. ) The primary parent and the final product of each series are indicated hy shading the hox of the respective elements. 

The uranium (4n + 2] series is the second of the three naturally occurring decay series on Earth. The half-life of the primary parent (T,/2 = 4.5 x 10 a) nearly matches the estimated age of the... 

The actinium (4n + 3) series is the third one of the naturaiiy occurring decay series on Earth. The haif-iife of the primary parent (T,/2 = 7.04 x 10 a - note, for comparison, that the Cambrian Period started some 5.7 x 10 years ago) is approximateiy one sixth of the estimated age of the Earth. Thus, nearly 2 part (or, more exactly, just about 1%) of the atoms that once existed are still potentially available as nuclear fuel... 

If Xjt is the longest-lived member of the series, then - after a sufficiently long time - the members Xi,..., Xk-i will die out, and the series will be shortened to the subseries Xfo Xjt+i,... with Xj(. as the primary parent. 

Note that the Geiger-Nuttall plot of the 4 -t 3 series is way above the 4n + 0 and 4n + 2 series (see Fig. 7.14). This is so because odd-Zand odd-N nuclei decay more slowly than even-even ones owing to shell effects. This kind of hindrance has saved, e.g., the very important even-odd nuclide g Ui43 - the primary parent of the 4 + 3 series - from extinction on Earth (Friedlander et al. 1981). 

Concordia diagram showing the effects of lead loss or uranium gain on U/Pb systems, fcryst is the time elapsed since original crystallization, fcios is the time elapsed since closure of the system after lead loss or uranium gain. A235 and A238 are the decay constants of the respective primary parents and... 

The importance of opportunities for informal interaction was emphasised by these West Hill Primary parents, among many others in the study ... 

Secondary and tertiary amines are named as N substituted derivatives of primary amines The parent primary amine is taken to be the one with the longest carbon chain The prefix N is added as a locant to identify substituents on the ammo nitrogen as needed... 

Amides. For primary amides the suffix -amide is added to the systematic name of the parent acid. For example, CH3—CO—NHj is acetamide. Oxamide is retained for HjN—CO—CO—NHj. The name -carboxylic acid is replaced by -carboxamide. 

A-substituted primary amides are named either (1) by citing the substituents as N prefixes or (2) by naming the acyl group as an N substituent of the parent compound. For example. 

Focants of substituents of symmetrically substituted derivatives of symmetrical amines are distinguished by primes or else the names of the complete substituted radicals are enclosed in parentheses. Unsymmetrically substituted derivatives are named similarly or as A-substituted products of a primary amine (after choosing the most senior of the radicals to be the parent amine). For example. 

Ketones oxidize about as readily as the parent hydrocarbons or even a bit faster (32). Although the reactivities of hydrogens on carbons adjacent to carbonyl groups are perhaps doubled, the effect is small because one methylene group is missing in comparison to the parent hydrocarbon. Ketones oxidize less readily than similar primary or secondary alcohols (35). 

Nitro alcohols form salts upon mild treatment with alkahes. Acidification causes separation of the nitro group as N2O from the parent compound, and results in the formation of carbonyl alcohols, ie, hydroxy aldehydes, from primary nitro alcohols and ketols from secondary nitro alcohols. 

Ritter Reaction (Method 4). A small but important class of amines are manufactured by the Ritter reaction. These are the amines in which the nitrogen atom is adjacent to a tertiary alkyl group. In the Ritter reaction a substituted olefin such as isobutylene reacts with hydrogen cyanide under acidic conditions (12). The resulting formamide is then hydroly2ed to the parent primary amine. Typically sulfuric acid is used in this transformation of an olefin to an amine. Stoichiometric quantities of sulfate salts are produced along with the desired amine. 

Oxidative Reactions. The majority of pesticides, or pesticide products, are susceptible to some form of attack by oxidative enzymes. For more persistent pesticides, oxidation is frequently the primary mode of metaboHsm, although there are important exceptions, eg, DDT. For less persistent pesticides, oxidation may play a relatively minor role, or be the first reaction ia a metaboHc pathway. Oxidation generally results ia degradation of the parent molecule. However, attack by certain oxidative enzymes (phenol oxidases) can result ia the condensation or polymerization of the parent molecules this phenomenon is referred to as oxidative coupling (16). Examples of some important oxidative reactions are ether cleavage, alkyl-hydroxylation, aryl-hydroxylation, AJ-dealkylation, and sulfoxidation. 

Preformed Peracids. Peracids can be generated at a manufacturing site and direcdy incorporated into formulations without the need for m situ generation. Two primary methods are utilized for peracid manufacture. The first method uses the equiUbrium shown in equation 22 to generate the peracid from the parent acid. 

Esmolol is iv adrninistered. Maximal P-adrenoceptor blockade occurs in 1 min. Its elimination half-life is about 9 min. EuU recovery from P-adrenoceptor blockade is within 30 min after stopping the infusion. The therapeutic plasma concentrations are 0.4—1.2 lg/mL. It is metabolized by hydrolysis in whole blood by red blood cell esterases resulting in the formation of a primary acid metabohte and free methanol. The metabohte is pharmacologically inactive. The resulting methanol levels are not toxic. Esmolol is 55% bound to plasma protein, the acid metabohte only 10%. Less than 2% of parent dmg and the acid metabohte are excreted by the kidneys. Plasma levels may be elevated and elimination half-hves prolonged in patients with renal disease (41). 

---