Stabilization defined

Extensive theoretical studies have been carried out to probe the nature of the allyl anion. These studies supplement and extend the experimental results. Allyl anion is of special interest because it is the simplest 7r-delocalized carbanion with 4 electrons and 3 Pjr-centers. Much recent theoretical discussion has concerned the role of resonance in the stabilization of such conjugated systems, a stabilization defined as the enthalpy difference between the localized double-bonded system and its conjugated state. The stabilization of allyl anion has generally been attributed to the delocalization of charge associated... 

P.Y.129 is not employed in plastics. The type of metal in the stabilizer defines how much of a color change is observed as the chelated metal in the pigment molecule is exchanged. Tin stabilizers produce red complexes, which, like corresponding lead or zinc chelates, respond very poorly to light and weather (see also Sec. 1.6.7). 

For the use as a contrast agent the stability of the complex in vivo is most important. It depends significantly on the thermodynamic stability defined by Eq.(l). 

Since the time of the cooling failure is unknown, it must be assumed that it occurs at the worse instant, that is, at the time where the accumulation is at a maximum and/or the thermal stability of the reaction mixture is critical. The amount of unconverted reactants and the thermal stability of the reaction mass may vary with time. Thus, it is important to know at which instant the accumulation, and therefore the thermal potential, is highest The thermal stability of the reaction mass may also vary with time. This is often the case when a reaction proceeds over intermediate steps. Hence, both the synthesis reaction and secondary reactions must be known in order to answer this question. The combination of a maximum accumulation with the minimum thermal stability defines the worst case. Obviously, the safety measures have to account for it. 

Chromophores must be thermally robust enough to withstand temperatures encountered in electric field poling and subsequent processing of chromophore/polymer materials. Chromophore decomposition temperatures can be assessed by techniques such as thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA and DSC measurements on neat chromophore samples in air will tend to yield decomposition temperatures lower than those for the same chromophores in hardened polymer lattices. Typically, to be useful for development of device quality materials, a chromophore must exhibit thermal stability of 250 °C or higher (with thermal stability defined as... 

Pourbaix diagrams are plots of (reversible) potential vs. pH for elements in pure water. They consist of regions of stability defined by lines as borders. Three types of lines exist on Pourbaix diagrams. Horizontal lines describe reactions that are dependent only on potential (e.g., Fe = Fe2+ + 2e ). Vertical lines describe reactions that are dependent only on pH (e.g., Fe2+ + 20H = Fe(OH)2). Angled lines correspond to reactions that depend on both potential and pH (e.g., 02 + 4H+ + 4e = 2H20). 

In conclusion, one may say that there is general agreement that theoretical predictions of nuclear stability define a range of superheavy elements in the vicinity of element 114 with sufficiently long half-lives to allow their study, provided they can be synthesized. 

The first peptides with an incorporated 4-amino-l,2-dithiolane-4-carboxylic acid residue (Adt), represented by structures 319 <2000BMCL1585>, 320 <2002BMCL147>, and 321 <2005PES104>, were synthesized in order to restrict their conformational mobility and stabilize defined secondary structures, thus making them chemically more stable and biochemically active. 

The Eddington limit, in brief, is a limit to hydrostatic stability defined by the condition that the outwards directed force induced by the radiation momentum balances the inwards directed gravity. We want to emphasise that, as a stability limit, the Eddington limit applies only to hydrostatic situations. This does not mean that radiation forces are unimportant in hydrodynamic situations (e.g stellar pulsations) however, a stability limit makes of course no sense in an unstable situation. 

The most important testing protocol for resistance to deterioration of critical physical properties upon exposure to heat, especially over prolonged periods of time, was designed by the Underwriters Laboratories (UL) [1], The UL temperature index is used to qualify materials for applications (such as use in electrical equipment) regulated by UL. The main purpose of these tests is to ensure that a polymer can be used safely for a prolonged period of time in these applications. A larger value of the UL temperature index implies greater stability, defined in... 

Mn(ii)-based SOD mimics is critical in determining the complex s SOD activity and stability. We have identified the frans-2,3-cyclohexano group as a substituent that increases both the SOD activity - and kinetic stability of the Mn complex. Figure 4 shows the SOD activities and kinetic stabilities (defined by the second-order rate constant (first-order in [H" ] and first-order in [Mn(L)] complex) of the unsubstituted SOD mimic SC-52608, the 2,3-(R,R)-trans-cyc-lohexano substituted SC-54417, and the 2,3-(f ,/ )-8,9-(R,R)-bis(tra s-cyc-lohexano) substituted SC-55858. The values for the dismutation of superoxide by these complexes increase as additional trans-cyclohexano groups are added, with SC-55858 = 1.20 x 10 M s ) having three times more... 

Application of the steady-state assumption for [AB ] yields the apparent recombination rate constant for stabilization, defined as d[AB]/ dt = fcrec[A][B],... 

Stability in sample solution (ST-3). Many solutes (analytes) readily decompose in sample solution prepared prior to TLC investigation. The stability of samples in a final sample solution may be determined from the system stability defined as a measure of bias in the assay results within a preselected time interval (in TLC, every hour up to 4-6 hours) determined by replicate analysis of the same ready-made sample solution, each time using freshly prepared standard solution for comparison. The results are evaluated for major and/or minor components. System stability is considered appropriate if the relative standard deviation calculated for the assay results obtained after different time periods does not exceed more than twice the corresponding value of system precision. If the value is higher, when the assay results are plotted as a function of time, the maximum duration of the usability of a sample solution can be calculated. 

Chemical Stability. Chemical stability defines an oil s ability to resist chemical change. Usually it, too, is used to refer to the oxidation stability of an oil. Chemical stability, other than resistance to oxidation, sometimes can refer to an oil s inertness in the presence of various metals and outside contaminants. 

In systems where the value of the X parameter is positive but the mixture is still in the range of single phase stability, defined by... 

Any kind of chelate formation has to enhance complex stability [51]. Hence, a possibly increased stability, defined as log of Cd(DHAP) or Cd(GlP), if... 

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