APPARENT EFFECTS

The water hberated during the cure has no apparent effect on the composite properties. Glass-filled composites prepared in this manner retain mechanical properties at elevated temperatures as well as solvent and flammabiUty resistance (88). PhenoHc-graphite-fiber composites that exhibit superior mechanical properties have also been prepared by this process. 

Ammonium Sulfamate. A number of flame retardants used for ceUulosic materials, including fabrics and paper products, are based on ammonium sulfamate (56). These products are water-soluble and therefore nondurable if treated fabrics are washed or exposed to weathering conditions. For most fabric and paper constmctions, efficient flame retardancy can be provided with no apparent effect on color or appearance and without stiffening or adverse effects on the feel of the fabrics. A wide variety of materials are treated, including ha2ardous work-area clothing, drapes, curtains, decorative materials, blankets, sheets, and specialty industrial papers (57). 

Size-dependent Crystal Growth. A number of empirical expressions correlate the apparent effect of crystal size on growth rate (30). The most commonly used correlation uses three empirical parameters to correlate growth rate with crystal size ... 

In applying this concept, the factor of particle size must be continuously borne in mind. A heterodisperse system can reach a steady state wherein the smaller particles are agglomerated and the larger particles are dispersed, giving the apparent effect of an equiUbrium. In ideal monodisperse systems under steady conditions, however, no such effects are noted. 

Halogenated Butyl Rubber. Halogenation at the isoprene site ia butyl mbber proceeds by a halonium ion mechanism leading to a double-bond shift and formation of an exomethylene alkyl haUde. Both chlorinated and brominated mbber show the predominate stmcture (1) (>80%), by nmr, as described eadier (33,34). Halogenation of the unsaturation has no apparent effect on the isobutylene backbone chains. Cross-linked samples do not crystallize on extension due to the chain irregularities introduced by the halogenated isoprene units. 

The reaction is second-order overall, with the rate given by A [R2C=0][NaBH4]. The interpretation of the rate data is complicated slightly by the fact that the alkoxyborohy-drides produced by the first addition can also fimction as reducing agents, but this has little apparent effect on the relative reactivity of the carbonyl compoimds. Table 8.3 presents some of the rate data obtained from these studies. 

It is particularly significant that no evidence is found for localized melting at particle interfaces in the inorganic materials studied. Apparently, effects commonly observed in dynamic compaction of low shock viscosity metals are not obtained in the less viscous materials of the present study. To successfully predict the occurrence of localized melting, it appears necessary to develop a more realistic physical model of energy localization in shock-compressed powders. 

Griskin et reported that there is no apparent effect of steam pressure on the rate of oxidation of Cr-Ni steels at temperatures between 600°C and 650°C at 10.1-20.2 MPa. Similar observations for Cr-Mo and Cr-Mo-V steels between 500°C and 600°C have been made by Wiles" . She compared low-alloy steel samples exposed to 101 kPa steam with power plant components that had operated for up to 150000b in steam at 17.25 MPa and found no significant difference in the oxidation rates (Fig. 7.11). 

As iS expected, atmosphericMi i tance is related to water and the icid formed from CO, SO, SO3, etc. The action of ultraviolet light has nb, apparent effect on vitrebus enamel uidike the. case with organic finishes. 

Table VI summarizes the results of tension tests on tinplate irradiated at 6-7.5 Mrad. Radiation had no apparent effect on the tensile...

Self-assembled monolayers are formed spontaneously by the immersion of an appropriate substrate into a solution of active surfactant in an organic solvent. After the substrate is immersed for a time from minutes to hours, it is rinsed with ligroin, methanol, distilled water, and dried in a steam of nitrogen. An apparent effect of the monolayer coating is the drastic change in wettability of the surface so that the measurement of the contact angle can be considered as an effective way to detect the formation of the SAMs. 

The adverse side-effects of the TCAs, coupled with their toxicity in overdose, provoked a search for compounds which retained their monoamine uptake blocking activity but which lacked the side-effects arising from interactions with Hj, aj-adreno-ceptors and muscarinic receptors. One of the first compounds to emerge from this effort was iprindole, which has an indole nucleus (Fig. 20.3). This turned out to be an interesting compound because it has no apparent effects on monoamine uptake and is not a MAO inhibitor. This, together with its relatively minor antimuscarinic effects, led to it commonly being described as an atypical antidepressant. Mechanisms that could underlie its therapeutic actions have still not been identified but, in any case, this drug has now been withdrawn in the UK. 

McGeer, P.L., Harada, N., Kimura, H., McGeer, E.G. and Schulzer, M. (1992). Prevalence of dementia amongst elderly Japanese with leprosy apparent effect of chronic drug therapy. Dementia 3, 146-149. 

Caldin has pointed out that in systems of chemical interest, P > a, and Eq. 10.10 can be reduced approximately to Eqs 10.11 and 10.12. The effect of Q is to increase the rate of reaction at a given temperature relative to that expected based on A and E. Therefore, Eq. 10.11 indicates that the greater the a/p, the greater will be the apparent effect of tunneling acceleration. ... 

Molecules 11 rapidly and irreversibly inhibit the DPP IV activity of the CD26 antigen, with IC50 values in the nanomolar range. Cycle enlargement ( = 4 instead of 2) improves inhibitory activity, whereas increasing the alkyl chain length on the sulfur atom R has no apparent effect. Other aminopeptidases are not inhibited. Molecules 11 inhibit DPP I V-p, an isoform of DPP IV, much more poorly.32,56... 

Halliday (1990), a Senior Veterinary Investigation Officer, records that he had an apparently effective response to the treatment of respiratory disease in calves, with a combination of Bryonia alba and Hepar sulphuris. In subsequent years, some animals with similar respiratory signs were left untreated as controls. They also recovered, apparently as rapidly and as effectively as the homoeopathically treated calves. 

There was a problem with this first version of the biochemical theory of depression. Iproniazid was not the only drug that had been reported to be effective as an antidepressant. Imipramine, the drug that had been tested by the Swiss psychiatrist Roland Kuhn, seemed to have similar effects. But imipramine is not an MAOI it does not inhibit the destruction of neurotransmitters in the synapse. So if antidepressants worked by inhibiting monoamine oxidase, why was imipramine effective How could its apparent effectiveness be reconciled with the chemical-imbalance theory ... 

According to EPA (1986a), lead was used in preparations sold as abortifacients in Britain around the turn of the century. These preparations were apparently effective at levels that produced marked signs of lead poisoning in the women. The available studies were methodologically inadequate and did not provide dose-effect information. Evidence for adverse reproductive outcomes in women with obvious lead poisoning is of little help in defining the effects of lead at much lower exposure levels. 

Vimpani GV, Baghurst PA, Wigg NR, et al. 1989. The Port Pirie cohort study—cumulative lead exposure and neurodevelopmental status at age 2 years Do HOME scores and maternal IQ reduce apparent effects of lead on Bayley Mental scores In Smith M. Grant LD, Sors A, eds. Lead exposure and child development An international assessment. Lancaster, UK Kluwer Academic Press. 

Acetonitrile, methanol and DMSO had no apparent effect on umbelliferone glucuronidation in human hepatocytes at concentration up to 2% [32]. With HLMs or expressed UGTs, inhibitory effects of organic solvents on glucuronidation of 7-hydroxy-4-trifluoromethyl-coumarin (7-HFC) and estradiol generally followed the order acetonitrile > ethanol > methonal > DMSO [33], DMSO did not inhibit estradiol-3-glucuronidation activity at a concentration up... 

It should be noted in conclusion that the experimentally observed influence of illumination on adsorption capacity is often only an apparent effect. 

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