Anomalous behavior

Stampfl C and Scheffler M 1997 Anomalous behavior of Ru for catalytic oxidation a theoretical study of the catalytic reaction CO+1/2 O2 to CO2 Phys. Rev. Lett. 78 1500... 

The freezing point diagram for the hydrazine—water system (Eig. 1) shows two low melting eutectics and a compound at 64 wt % hydrazine having a melting point of —51.6°C. The latter corresponds to hydrazine hydrate [7803-57-8] which has a 1 1 molar ratio of hydrazine to water. The anomalous behavior of certain physical properties such as viscosity and density at the hydrate composition indicates that the hydrate exists both in the Hquid as well as in the soHd phase. In the vapor phase, hydrazine hydrate partially dissociates. 

Acute oral LD q data for nitro alcohols in mice are given in Table 1. Because of their low volatiHty, the nitro alcohols present no vapor inhalation ha2ard. They are nonirritating to the skin and, except for 2-nitro-1-butanol, are nonirritating when introduced as a 1 wt % aqueous solution in the eye of a rabbit. When 0.1 mL of 1 wt % commercial-grade 2-nitro-1-butanol in water is introduced into the eyes of rabbits, severe and permanent corneal scarring results. This anomalous behavior may be caused by the presence of a nitro-olefin impurity in the unpurifted commercial product. 

During the researeh of equilibrium of the anion surfaetants assoeiates with rhodamine 6G extraetion we are found anomalous behavior of assoeiates with the anions of higher earbonie aeids. The extraetion of sueh ionie assoeiates appears in narrow pH range 8-10. As in this narrow pH range earbonie aeids are eompletely dissoeiated, it was obvious, that the extraetion is determined by the eondition of the partieles of rhodamine 6G. 

A similar anomalous behavior has been detected also in 3d polymer melts but only for rather short chains [41] for longer chains, several regimes occur because of the onset of entanglement (reptation ) effects. In two dimensions, of course, the topological constraints experienced by a chain from... 

The anomalous behavior of quinazoline was first discovered by Albert et who made the surprising observation that 4-methyl-quinazoline 2.5) was a weaker base than quinazoline (pA 3.5). Mason then observed that the ultraviolet spectrum of the quinazoline cation was abnormal but that the spectrum of 4-methylquin-azoline was normal (see Fig. 2). These anomalies led to the suggestion that water adds covalently to the cation of quinazoline to give 12 (R = H). The occurrence and position of hydration were confirmed by a detailed study of the ultraviolet and infrared spectra of the anhydrous and hydrated hydrochlorides and by mild oxidation of the cation to 4(3 )-quinazolinone. Using the rapid-reaction technique (the continuous-flow method), the spectrum of the unstable... 

A similar explanation may account for the slight deviations exhibited by normal substances, but fails to explain the anomalous behavior of the monatomic gases. A mechanical interpretation of the theorem of corresponding states has, how ever, been advanced by Earnerlingh Onnes ( Principle of Uniformity ) which appears to embrace all known cases. 

Meyers212 collected together several examples of the anomalous behavior of sulfones in which the group was close to the reaction center and interpreted these in terms of the negative direct field effect of the S02 oxygen atoms (cf. Meyers and colleagues141). 

Figure 10. Isotherms of internal mobilities in various binary nitrates containing Ag as one cation. (Reprinted from I. Okada and P.-H. Chou, Anomalous Behavior of Internal Mobilities for Ag(I) and T1(I) Ions in Molten Nitrates, J. Electrochem. Soc. 144 (4) 1333, 1997, Fig.2. Reproduced by permission of the Electrochemical Society, Inc.)...

TTx represents the hydrophobicity of the substituents at position 10. Its positive coefficient (+0.75) suggests that the presence of highly hydrophobic substituents at position 10 increases the activity. The outlier (X = OH) is much more active than expected by 11 times the standard deviation. This may be due to the formation of a phenoxyl radical that interacts with DNA [48]. The other derivative (X = NH2) is also considered as an outher due to being much more active than expected by 14 times the standard deviation. This anomalous behavior may be attributed to its nature as an aniline. This could result in hydrogen abstraction, or involve microsomal N-oxidation [48,49]. 

The method proposed to deal with polycrystalline adsorbent is highly promising while considering polycrystalline composites, the latter being mixtures of various oxides used as adsorbents who made chemical sensors [175, 177]. It was established in above papers that mixtures of various oxides exhibit the highest sensitivity to specific gases. Moreover, in several cases the adsorption-caused response in electrophysical parameters of such composites exhibit anomalous behavior [58, 176, 177],... 

Mathematical methods for determining the gas holdup tine are based on the linearity of the plot of adjusted retention time against carbon number for a homologous series of compounds. Large errors in this case can arise from the anomalous behavior of early members of the homologous series (deviation from linearity in the above relationship). The accuracy with which the gas holdup time is determined by using only well retained members of a homologous series can be compromised by instability in the column temperature and carrier gas flow rate [353,357]. The most accurate estimates... 

The other anomalous behavior was the smaller-than-expected permeability of highly branched compounds. This deviation has been explained on the basis that membrane lipids are subject to a more highly constrained orientation (probably a parallel configuration of hydrocarbon chains of fatty acids) than are those in a bulk lipid solvent. As a result, branched compounds must disrupt this local lipid structure of the membrane and will encounter greater steric hindrance than will a straight-chain molecule. This effect with branched compounds is not adequately reflected in simple aqueous-lipid partitioning studies (i.e., in the K0/w value). 

Hayashi, T., Nagai, Y. (1980). The anomalous behavior of collagen peptides on sodium dodecyl sulfate-polyacrylamide gel electrophoresis is due to the low content of hydrophobic amino acid residues. J. Biochem. (Tokyo) 87, 803-808. 

It is more difficult to interpret micellar effects upon reactions of azide ion. The behavior is normal , in the sense that k /kw 1, for deacylation, an Sn2 reaction, and addition to a carbocation (Table 4) (Cuenca, 1985). But the micellar reaction is much faster for nucleophilic aromatic substitution. Values of k /kw depend upon the substrate and are slightly larger when both N 3 and an inert counterion are present, but the trends are the same. We have no explanation for these results, although there seems to be a relation between the anomalous behavior of the azide ion in micellar reactions of aromatic substrates and its nucleophilicity in water and similar polar, hydroxylic solvents. Azide is a very powerful nucleophile towards carboca-tions, based on Ritchie s N+ scale, but in water it is much less reactive towards 2,4-dinitrohalobenzenes than predicted, whereas the reactivity of other nucleophiles fits the N+ scale (Ritchie and Sawada, 1977). Therefore the large values of k /kw may reflect the fact that azide ion is unusually unreactive in aromatic nucleophilic substitution in water, rather than that it is abnormally reactive in micelles. 

---