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NO OBSERVABLE

For a molecule that has no observable tiumelling between minima on the potential energy surface (i.e., for a... [Pg.180]

Transition intensities are detennined by the wavefiinctions of the initial and final states as described in the last sections. In many systems there are some pairs of states for which tire transition moment integral vanishes while for other pairs it does not vanish. The temi selection rule refers to a simnnary of the conditions for non-vanishing transition moment integrals—hence observable transitions—or vanishing integrals so no observable transitions. We discuss some of these rules briefly in this section. Again, we concentrate on electric dipole transitions. [Pg.1133]

The nitric acid used in this work contained 10% of water, which introduced a considerable proportion of acetic acid into the medium. Further dilution of the solvent wnth acetic acid up to a concentration of 50 moles % had no effect on the rate, but the addition of yet more acetic acid decreased the rate, and in the absence of acetic anhydride there was no observed reaction. It was supposed from these results that the adventitious acetic acid would have no effect. The rate coefficients of the nitration diminished rapidly with time in one experiment the value of k was reduced by a factor of 2 in i h. Corrected values were obtained by extrapolation to zero time. The author ascribed the decrease to the conversion of acetyl nitrate into tetranitromethane, but this conversion cannot be the explanation because independent studies agree in concluding that it is too slow ( 5.3.1). [Pg.86]

Chemical Properties. Without inhibitors, tetrahydrofurfuryl alcohol is susceptible to autoxidation, developing color and carbonyl functionality. In the absence of air, however, no observable changes occur even after several years storage. In the presence of air, if a stabilizer such as Naugard is added, tetrahydrofurfuryl alcohol remains colorless after protracted periods of storage. Peroxide accumulation is low, not dangerous, and readily dischargeable on redistillation. [Pg.82]

Undiluted DMAMP, AMP-95, and AB cause eye bums and permanent damage, if not washed out immediately. They are also severely irritating to the skin, causing bums by prolonged or repeated contact. Of these three aLkanolarnines, only AMP has been studied in subchronic and chronic oral studies. The principal effect noted was the action of AMP on the stomach as a result of its alkalinity. The no-observed-effect level (NOEL) in a one-year feeding study in dogs was 110 ppm in the diet. In general, the low volatility and appHcations for which these products are used preclude the likelihood of exposure by inhalation. [Pg.18]

Aquatic toxicity is reported in mg/L for Pimepha/espromealas (fathead minnow), 69-h LC q 7650 (17) for Daphnia magna (water flea), 48-h EC q 3310 (18) for Mjriophjllum spicatum (water milfoil), phytotoxicity (EC q for growth) 5962 (19) and for Pana breviceps (frog), no observed effect concentration (NOEC) 400 (20). LC q and EC q are lethal and effect concentrations, respectively, for 50% of the subjects tested. [Pg.185]

Aquatic toxicity is becoming (ca 1997) a permit requirement on all discharges. Aquatic toxicity is generally reported as an LC q (the percentage of wastewater which causes the death of 50% of the test organisms in a specified period ie, 48 or 96 h, or as a no observed effect level (NOEL), in which the NOEL is the highest effluent concentration at which no unacceptable effect will occur, even at continuous exposure. [Pg.178]

Administration of 5 ppm barium, the acetate, to mice in the drinking water in a life-time study had no observable effects on longevity, mortality, and body weights, or on the incidence of tumors (53). Long-term studies in rats exposed to Ba " in drinking water containing 5 mg/L, as acetate, or 10—250 mg/L, as chloride, resulted in no measurable toxic effects (47). [Pg.483]

No observed adverse effect at this concentration in H2O 72 h static test (33) unless otherwise noted. [Pg.49]

Georgakopoulos and Broucek (1987) investigated the effect of recycle ratio on non-ideality, both mathematically and experimentally. They investigated two cases from which the bypass case b was completely uninteresting, because total bypass of the catalyst bed could be avoided by feeding the makeup directly to the location of highest sheerfield, at the tip of the impeller blade. For their case a they showed on their Fig. 3. that from a recycle ratio of about 10 = 32 there was no observable falsification effect. This matched well the conclusion of Pirjamali et al. [Pg.146]

Something else should be said about the impact of accommodation- When the (general) theory concerned is strongly supported independently of the fact at issue, the accommodation of some fact, even in this ad hoc way, may well still supply the best explanation that science can currently supply for that fact. So, for example, the best explanation in, say, 1700 for the observation of no stellar parallax was surely the Copemican one—that there must in fact be an apparent parallactic motion but that even the nearest stars are so far away as to make the effect too small to be detected by even the best available telescopes. (Here, as before with Ptolemy and with scientific creationism, we use the phenomenon—no observed parallax—to fix (in this case in a rather loose way) an otherwise free parameter in the theory (distance to the nearest star).)... [Pg.62]

In other words, there are no observable consequences of the one-particle systems in the absence of external perturbations besides these the mass of the one-electron state is m, that of the photon is zero, the electric charge of the negaton is — e,10 and that of the positon, +e. [Pg.708]

Electrochemical oxidation of thiosulphinates leads cleanly to the corresponding thiosulphonate in reasonable yields with no observed side-products203. [Pg.992]


See other pages where NO OBSERVABLE is mentioned: [Pg.136]    [Pg.172]    [Pg.178]    [Pg.425]    [Pg.203]    [Pg.148]    [Pg.133]    [Pg.539]    [Pg.489]    [Pg.3]    [Pg.326]    [Pg.427]    [Pg.427]    [Pg.266]    [Pg.121]    [Pg.120]    [Pg.115]    [Pg.117]    [Pg.253]    [Pg.399]    [Pg.1092]    [Pg.425]    [Pg.342]    [Pg.609]    [Pg.37]    [Pg.56]    [Pg.710]    [Pg.528]    [Pg.112]    [Pg.81]    [Pg.366]    [Pg.26]    [Pg.93]    [Pg.288]    [Pg.45]   


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NO OBSERVABLE ADVERSE) EFFECT

NO observations

NO observations

NOAELs (no-observed adverse effect

No Observable Adverse Effect Levels NOAELs)

No Observed Adverse Effect Level

No Observed Effect Level

No observable adverse effect level NOAEL)

No observable effect concentration

No observable effect level

No observed

No observed

No observed adverse

No observed adverse effect

No observed adverse effect level NOAEL)

No observed effect concentration

No observed effect concentration NOEC)

No observed effect concentrations NOECs)

No observed effects

No-observable effect level NOEL)

No-observable-adverse-effect level

No-observable-effect concentrations NOECs)

No-observed-adverse-effect concentration

No-observed-adverse-effect concentration NOAEC)

The no observed adverse effect level

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