Pseudo event

For the modem vkual celebrity as specifically representing the human pseudo event, see Boorstin, The Image, 4d 76, 154—61 ( Star ). For a novel approach to post-modern celebrities, see Moffitt, Picturing Extraterrestrials. 

The Image A Guide to Pseudo Events in America. New York Colophon, 1964-... 

The dependence of the failure of pipe 1 on the rupture of pipe 2 is expressed by a conditional probability to be assigned to primary event X3. The latter represents a so-called pseudo-event. Its probability of occurrence must be derived from statistics, if available, or pertinent model calculations. In this case the models would be from the areas of fracture mechanics and thermohydraulics. If no information is available, estimates are the only recourse. A pessimistic estimate is a value of 1, i.e. the failure of pipe 2 always causes pipe 1 to fail. 

By introducing pseudo-events the fault tree becomes more complex. This may lead to a more laborious evaluation. 

The cumulative effect of such reports was to establish predictions whose truth was guaranteed by the way in which the event, non-event or pseudo-event it referred to was reported. 

The two main termination steps for neutral solutions are HO + HO — H2O2 + 2 O3 and HO + HO3 — H2O2 + O3 + O2. An alternative mechanism has been proposed that does not involve HO and HO but has a different initiation step (26). Three ozone molecules are destroyed for each primary event. In the presence of excess HO radical scavengers, ie, bicarbonate, the pseudo-first-order rate constant at 20°C for the initiation step is 175 X. This yields an ozone half-hfe of 66 min at pH 8. In distilled water = 50 mmol/L), the half-hfe is significantly lower, ie, 7 min. 

The starting point is the (pseudo-) randomization function supplied with most computers it generates a rectangular distribution of events, that is, if called many times, every value between 0 and 1 has an equal probability of being hit. For our purposes, many a mathematician s restraint regarding randomization algorithms (the sequence of numbers is not perfectly random because of serial correlation, and repeats itself after a very large number of... 

Let us consider the possible events following excitation of an acid AH that is stronger in the excited state than in the ground state (pK < pK). In the simplest case, where there is no geminate proton recombination, the processes are presented in Scheme 4.6, where t0 and Tq are the excited-state lifetimes of the acidic (AH ) and basic (A- ) forms, respectively, and ki and k i are the rate constants for deprotonation and reprotonation, respectively, kj is a pseudo-first order rate constant, whereas k i is a second-order rate constant. The excited-state equilibrium constant is K = k /k 7 ... 

Figure 10.12—Sequence of events necessary to obtain a pseudo-double beam spectrum with a Fourier transform IR spectrometer. The instrument records and stores in its memory two spectra representing the variation of lu (blank) and / (sample) as a function of wavenumber (emission spectra 1 and 2 above). Then, it calculates the conventional spectrum, which is identical to that obtained on a double beam instrument, by calculating the ratio T — /// — f(A) for each wavenumber. Atmospheric absorption (CO2 and H20) is thus eliminated. The figure illustrates the spectrum of a polystyrene film.

Such observations have led to the idea that depression may be a pseudomonoamine deficiency due to a deficiency in signal transduction from the monoamine neurotransmitter to its postsynaptic neuron in the presence of normal amounts of neurotransmitter and receptor. If there is a deficiency in the molecular events that cascade from receptor occupancy by neurotransmitter, it could lead to a deficient cellular response and thus be a form of pseudomonoamine deficiency (i.e., the receptor and the neurotransmitter are normal, but the transduction of the signal from neurotransmitter to its receptor is somehow flawed). Such a deficiency in molecular functioning has been described for certain endocrine diseases such as hypoparathyroidism (parathyroid hormone deficiency), pseudohypoparathyroidism (parathyroid receptors deficient but parathyroid hormone levels normal), and pseudo-pseudohypoparathyroidism (signal transduction deficiency leading to hypoparathyroid clinical state despite normal levels of hormone and receptor). 

With the neutral [(RCN)2PdCl2] pro-catalyst system (Fig. 12.3, graph iv), computer simulation of the kinetic data acquired with various initial pro-catalyst concentrations and substrate concentrations resulted in the conclusion that the turnover rates are controlled by substrate-induced trickle feed catalyst generation, substrate concentration-dependent turnover and continuous catalyst termination. The active catalyst concentration is always low and, for a prolonged phase in the middle of the reaction, the net effect is to give rise to an apparent pseudo-zero-order kinetic profile. For both sets of data obtained with pro-catalysts of type B (Fig. 12.3), one could conceive that the kinetic product is 11, but (unlike with type A) the isomerisation to 12 is extremely rapid such that 11 does not accumulate appreciably. Of course, in this event, one needs to explain why the isomerisation of 11 now proceeds to give 12 rather than 13. With the [(phen)Pd(Me)(MeCN)]+ system, analysis of the relative concentrations of 11 and 13 as the conversion proceeds confirmed that the small amount of... 

As shown in Fig. 14, the cathode potential changes abruptly across the H2/air-front. This fact warrants the inclusion of the pseudocapacitance into the previous steady-state kinetic model.12 It is clear that the electrode s pseudo-capacitance can supply protons in transient events and thereby reduce the cathode carbon-support corrosion rate in the case of fast moving H2/air- ronts. Figure 18... 

Therefore, for equal H2/air-front residence times, the pseudo-capacitive model would suggest lower rates of carbon-support oxidation, i.e., lower rates of C02 formation for the stop process if compared to the start process, which is consistent with on-line C02 measurements of the air exiting the cathode flow-field during H2/air-front start-stop events, as shown in Fig. 16. 

Since the time scales for establishing local H2 starvation events are on the order of seconds or 10 s of seconds,11,14 pseudo-capacitive effects will not be important. 

When the process pN- n-> pv in the mobile phase or stationary phase can be represented by first-order or pseudo-first-order interconversion kinetics and as a reversible binding event, the resolution of the interconverting species can be evaluated319 by treating the column as a chemical reactor with properties specified by the corresponding Damkohler number Da and the corresponding interconversion rate constants derived. Thus,... 

Dissolution Kinetics. Pseudo first-order reactions are widely employed in the field of soil-water environmental science for evaluating physical, chemical, or biochemical events. A pseudo first-order dissolution example is given below to demonstrate the use of kinetics in identifying or quantifying minerals in simple or complex systems. Consider a metal carbonate solid (MC03s) reacting with a strong acid (HC1) ... 

A frequent theme in alcohol carbonylations by transition metals is the use of a halide or pseudo-halide promoters or cocatalysts. Despite major problems of corrosion associated with its use, iodide is almost always found to be most effective in this capacity. This is because the halide serves several purposes, for each of which iodide is ideally suited. One of the most important roles of these anion promoters can be that of facilitating the formation of metal-carbon bonds via the formation of intermediate alkyl halides. Under typical catalytic conditions for a variety of systems, at least some portion of the added halide is converted to the corresponding strong halo-acid. In fact, conditions are generally set so that this event is maximized. 

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