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Strong control

In lower pressure environments, the wave profiles are dominated by the consequences of deformation of the samples to fill the voids. This irreversible crush-up process strongly controls the wave speeds, which have anomalously low values at low initial sample densities. Modeling of this problem is... [Pg.50]

The shock-compression events are so extreme in intensity and duration, and remote from direct evaluation and from other environments, that experiment plays a crucial role in verifying and grounding the various theoretical descriptions. Indeed, the material models developed and advances in realistic numerical simulation are a direct result of advances in experimental methods. Furthermore, the experimental capabilities available to a particular scientist strongly control the problems pursued and the resulting descriptions of shock-compressed matter. Given the decisive role that experimental methods play, it is essential that careful consideration be given to their characteristics. [Pg.53]

The maximal accessible depression of the surface tension of aqueous solutions of disodium alkanephosphonates is strongly controlled by the length of the carbon chain. There is a similar dependence of foamability on the length of the alkyl chain [188], as is shown in Table 8. [Pg.593]

Environmental conditions determine in large part the chemical reactions that will occur when waste is injected. For example, precipitation-dissolution reactions are strongly controlled by pH. Thus, iron oxides, which may be dissolved in acidic wastes, may precipitate when injection-zone mixing increases the pH of the waste. Similarly, redox potential (Eh) exerts a strong control on the type of microbiological degradation of wastes. [Pg.806]

Studies carried out with free or entrapped cells have greatly contributed to the characterization of basic phenomena involved in dye conversion. However, from the practical standpoint, scale-up of processes based on either free or entrapped cells is not economically feasible. In fact, the first choice is usually associated with prohibitively large reaction volumes. The second choice is typically expensive and asks for industrial wastewaters of strongly controlled composition for the stability of entrapment matrixes to be preserved. [Pg.109]

Precipitation can occur if a water is supersaturated with respect to a solid phase however, if the growth of a thermodynamically stable phase is slow, a metastable phase may form. Disordered, amorphous phases such as ferric hydroxide, aluminum hydroxide, and allophane are thermodynamically unstable with respect to crystalline phases nonetheless, these disordered phases are frequently found in nature. The rates of crystallization of these phases are strongly controlled by the presence of adsorbed ions on the surfaces of precipitates (99). Zawacki et al. (Chapter 32) present evidence that adsorption of alkaline earth ions greatly influences the formation and growth of calcium phosphates. While hydroxyapatite was the thermodynamically stable phase under the conditions studied by these authors, it is shown that several different metastable phases may form, depending upon the degree of supersaturation and the initiating surface phase. [Pg.12]

Establish strong controls over any medium that is used as a backdoor into the SCADA network. [Pg.130]

Alkyl- and aryl-hydrazones of aldehydes and ketones readily peroxidise in solution and rearrange to azo hydroperoxides [1], some of which are explosively unstable [2], Dry samples of the p-bromo- and p-fluoro-hydroperoxybenzylazobenzenes, prepared by oxygenation of benzene solutions of the phenylhydrazones, exploded while on filter paper in the dark, initiated by vibration of the table or tapping the paper. Samples were later stored moist with benzene at —60°C to prevent explosion [3], A series of a-phenylazo hydroperoxides derived from the phenyl-or p-bromophcnyl-hydrazones of acetone, acetophenone or cyclohexanone, and useful for epoxidation of alkenes, are all explosive [4], The stability of several substituted phenylazo hydroperoxides was found to be strongly controlled by novel substituent effects [5],... [Pg.336]

We wish to stress that comparison of the isotopic effects in biologic and abiologic systems will be most meaningful if experimental conditions are identical, where the only difference is the presence or absence of bacteria. The wide variety of buffers, growth media, and others conditions that are involved in biological experiments raise the possibihty that spurious results may be obtained if these factors are not carefully controlled. Because speciation may exert a strong control on Fe isotope fractionations (Schauble et al. 2001), even small differences across experimental studies may be significant. [Pg.392]

Contents of REE in massive sulfides from the BMC are strongly controlled by the abundance of and REE concentrations in phosphate minerals, specifically apatite, xenotime and monazite. Strong positive Eu anomalies in apatite, account for the anomalous Eu signatures of exhalative sulfides whereas REE in monazite masses are largely reflective of detrital sources and may mask hydrothermal signatures. Limited release of mobile trace elements (LREE and Eu) during green-schist facies metamorphism has partly modified REE profiles for VMS deposits of the BMC. [Pg.180]

A comparison of a series of [YCo(cod)] catalysts in the test reaction (Scheme 5) under identical conditions in the continuous-flow apparatus (Fig. 1) has revealed that the reaction temperature required for 65% pro-pyne conversion depends on the nature of the controlling ligand Y. Further, an inspection of Table VIII reveals that both the Arrhenius energy of activation Ea for the reaction and the selectivity of the catalyst are strongly controlled by the ligand Y [85AG264, 85AG(E)248]. [Pg.214]

It was shown that the protonation regioselectivity was strongly controlled by methoxy and hydroxyl substituents, whose directive effects overwhelmed the methyl substitution effects." Regiocontrol by —OMe and —OH substituents, and its stronger influence relative to methyl groups, was also observed in the nitration and bromination reactions (Fig. 21). Regioselectivities observed in the nitration and bromination reactions in representative cases were the same as those via protonations. [Pg.159]

While protonation regioselectivity in the parent systems corresponded to the energetically most favored carbocations computed by DFT, selectivity in the OMe-substituted derivatives was strongly controlled by the methoxy group. Benzofiuorenes 81,83,84, and 85, and dibenzofluorenes 86 and 88 were nitrated under very mild conditions. Nitration... [Pg.171]

Thus, the average fidelity of the transfer has an involved dependence on the modulation V t) and the transfer time The problem at hand is to find the optimal transfer that minimizes the average infidelity at time 1 - Obviously, zero infidelity is obtainable for infinitely fast (zero-time) transfer, if we allow infinitely strong control. Since this is unphysical, we add a constraint on the total energy E of the transfer process... [Pg.192]


See other pages where Strong control is mentioned: [Pg.1949]    [Pg.144]    [Pg.380]    [Pg.170]    [Pg.372]    [Pg.481]    [Pg.266]    [Pg.335]    [Pg.193]    [Pg.200]    [Pg.67]    [Pg.538]    [Pg.1653]    [Pg.352]    [Pg.362]    [Pg.438]    [Pg.322]    [Pg.123]    [Pg.340]    [Pg.45]    [Pg.655]    [Pg.664]    [Pg.23]    [Pg.178]    [Pg.178]    [Pg.465]    [Pg.146]    [Pg.196]    [Pg.245]    [Pg.468]    [Pg.679]    [Pg.538]    [Pg.1699]    [Pg.545]    [Pg.418]    [Pg.20]   
See also in sourсe #XX -- [ Pg.145 , Pg.276 ]




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