Wavelength unstable

The smallness or the spectral changes observed between corresponding pairs of cations and neutral molecules enables the main features of the spectra of unstable species such as the hydrated neutral molecule or the anhydrous cation of pteridine to be predicted from the spectra of the hydrated cation and anhydrous neutral molecule, respectively. In this way, suitable wavelengths can readily be selected at which hydration and dehydration will produce big changes in the optical density. 

When 1, 3, 3-triethoxypropene was hydrolyzed with IN sulfuric acid, a solution of malonaldehyde whose optical density was perfectly stable at 350 m/x for at least one week was obtained. If the solution was made alkaline, the optical density at the same wavelength increased by a small value and then remained virtually constant for at least one week (56). It was also observed that in these solutions the extinction coefficient at 350 m/x was very low (observed 8.3, 61.5 and 69, for solutions of pH 0.4, 7.15 and 9.4 respectively) compared with previously reported values which varied from 200 ( 40) to 1000 ( 48). On the other hand, the absorption of solutions having a pH of 3 to 5, increased considerably with time (at pH 4.75, the extinction coefficient of malonaldehyde at 350 m/x was initially about 40 after four weeks a value of about 930 was recorded and the optical density of the solution was still increasing). This increase in absorption was accompanied by a marked decrease in the malonaldehyde content of the solution, as measured by the thiobarbituric acid method. As a corollary, it was found that aqueous solutions of malonaldehyde, prepared by autocatalyzed hydrolysis (33) of the same acetal and which had a pH of about 3.5, showed, at the completion of the hydrolysis, considerably higher extinction coefficient values at 350 m/x than did those malonaldehyde solutions which were prepared by hydrolysis with IN acid and subsequently adjusted to pH 4. It appears, therefore, that at pH values at which most of the periodate oxidations are carried out, malonaldehyde is unstable and undergoes a chemical reaction, the nature of which is not, as yet, known. 

Nitric Acid. Anhyd perchloric ac reacts with 100% nitric ac to form nitronium perchlorate (02N+C104-) (see below) and hydroilium perchlorate (see above under hydrates) (Ref 16) Ozone. Anhyd perchloric ac reacts with ozone when irradiated with light of wavelength 254my to give HOOCIO3, which is unstable and decomps to 0 and chloric ac (Ref 25)... 

Whereas currently most studies deal with azides, a similar effort devoted to other metal salts such as nitrates and chlorates would be an important step toward understanding electrical initiation of pyrotechnics, and conversely to making possible safe, non-expl igniters. For instance, a study by Maycock (Ref 4) shows that those azides, perchlorates, and nitrates in which the solid state shows absorption on the long wavelength side of the anionic excitation band in soln, are the most unstable members of the respective series. Consequently, there is a direct relationship between the absorption spectra of pyrotechnic oxidizers and their respective sensitivities... 

Excess of the reagent hydrolyses to a non-fluorescent residue and the reagent itself does not fluoresce. The optimum wavelength of the excitation light is 390 nm and that of the emitted light 475 nm. This regent is, however, less sensitive than Fluoropa and the derivative is unstable consequently, it must be injected onto the column immediately after formation if used in pre-column derivatization. It has been used successfully in the separation and analysis of polyamines (32), catecholamines (33) and amino acids (34). 

We have shown that planar premixed hydrocarbon-air flames are unstable over a range of wavelengths, typically from several centimeter to a few millimeter. The only exception is for slow flames propagating downward. 

Moissis and Berenson (1962) also derived the pool boiling CHF on horizontal surfaces by means of hydrodynamic transitions. Instead of taking 0 between values of f and d, they used the most unstable wavelength as proportional to the jet diameter, DJt... 

This problem is very important, but it is extremely difficult to make SAXS measurements at higher temperatures because the induction period becomes too short to observe the time evolution of SAXS intensities. For example, as was seen in Sect. 2.2, the induction period was only 100 s when the PET glass was crystallized even at 115 °C, 40 K higher than Tg, where a detailed analysis of the SAXS data was impossible. Of course, as the crystallization temperature approaches the melting temperature, the induction period is expected to become longer. However, as will be shown below, no characteristic peaks of SD could be detected in SAXS curves either. This is probably because the crystallization temperature was not in the unstable state, or the characteristic wavelength was much larger compared with the lower resolution limit of... 

The gamma ray is a photon of electromagnetic radiation with a very short wavelength and high energy. It is emitted from an unstable atomic nucleus and has high penetrating power. 

The morphological stability of initially smooth electrodeposits has been analyzed by several authors [48-56]. In a linear stability analysis, the current distribution on a low-amplitude sinusoidal surface is found as an expansion around the distribution on the flat surface. The first order current distribution is used to calculate the rate of amplification of the surface corrugation. A plot of amplification rate versus mode number or wavelength separates the regimes of stable and unstable fluctuation and... 

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