Unpredictability

They are prepared by the action of HNO2 on aromatic amines. The amine is dissolved in excess of mineral acid and sodium nitrite is added slowly until a slight excess of HNO2 is present. The reaction is usually carried out in ice-cold solution. The solution then contains the diazonium salt of the mineral acid used, anhydrous diazonium salts of unpredictable stability may be precipitated with complex anions like PF , SnCl6 BF4 . 

PPha, pyridine) organic groups (olefines, aromatic derivatives) and also form other derivatives, e.g. halides, hydrides, sulphides, metal cluster compounds Compounds containing clusters of metal atoms linked together by covalent (or co-ordinate) bands, metaldehyde, (C2H40) ( = 4 or 6). A solid crystalline substance, sublimes without melting at I12 1I5" C stable when pure it is readily formed when elhanal is left in the presence of a catalyst at low temperatures, but has unpredictable stability and will revert to the monomer, ft is used for slug control and as a fuel. 

The N/G ratio is usually not oonstant across a reservoir and may change over quite short distances from 1.0 (100% reservoir) to 0.0 (no reservoir) in some depositional environments. Reservoirs with a low or unpredictable N/G ratios often require large numbers of wells to access reserves and are therefore more expensive to develop. 

The example just shown assumed one discount rate and one oil price. Since the oil price is notoriously unpredictable, and the discount rate is subjective, it is useful to calculate the NPV at a range of oil prices and discount rates. One presentation of this data would be in the form of a matrix. The appropriate discount rates would be 0% (undiscounted),.say 10% (the cost of capital), and say 20% (the cost of capital plus an allowance for risk). The range of oil prices is again a subjective judgement. 

There is some uncertainty connected with testing techniques, errors of characteristic measurements, and influence of fectors that carmot be taken into account for building up a model. As these factors cannot be evaluated a priori and their combination can bring unpredictable influence on the testing results it is possible to represent them as additional noise action [4], Such an approach allows to describe the material and testing as a united model — dynamic mathematical model. 

Gas A, by itself, adsorbs to a of 0.02 at P = 200 mm Hg, and gas B, by itself, adsorbs tod = 0.02 at P = 20 mm Hg Tisll K in both cases, (a) Calculate the difference between (2a and (2b> the two heats of adsorption. Explain briefly any assumptions or approximations made, ib) Calculate the value for 6 when the solid, at 77 K, is equilibrated with a mixture of A and B such that the final pressures are 200 mm Hg each, (c) Explain whether the answer in b would be raised, lowered, or affected in an unpredictable way if all of the preceding data were the same but the surface was known to be heterogeneous. The local isotherm function can still be assumed to be the Langmuir equation. 

Extended defects range from well characterized dislocations to grain boundaries, interfaces, stacking faults, etch pits, D-defects, misfit dislocations (common in epitaxial growth), blisters induced by H or He implantation etc. Microscopic studies of such defects are very difficult, and crystal growers use years of experience and trial-and-error teclmiques to avoid or control them. Some extended defects can change in unpredictable ways upon heat treatments. Others become gettering centres for transition metals, a phenomenon which can be desirable or not, but is always difficult to control. Extended defects are sometimes cleverly used. For example, the smart-cut process relies on the controlled implantation of H followed by heat treatments to create blisters. This allows a thin layer of clean material to be lifted from a bulk wafer [261. 

Chaotic attractors are complicated objects with intrinsically unpredictable dynamics. It is therefore useful to have some dynamical measure of the strength of the chaos associated with motion on the attractor and some geometrical measure of the stmctural complexity of the attractor. These two measures, the Lyapunov exponent or number [1] for the dynamics, and the fractal dimension [10] for the geometry, are related. To simplify the discussion we consider tliree-dimensional flows in phase space, but the ideas can be generalized to higher dimension. 

The roles of phosphines are not clearly understood and are unpredictable. Therefore, in surveying optimum conditions of catalytic reactions, it is advisable to test the activity of all these important types of phosphines and phosphites. which have different steric effects and electron-donating properties. 

These unpredicted Avrami exponents may be indications that multiple mechanisms are operative and/or that f and/or N is itself a function of d. 

The use of automatic machine tools, often computer controlled and programmable, requires abrasive elements which have performance and lifetime reproductibihty. Natural abrasives suffer on both counts performance is limited and inconsistent quaUty leads to unpredictable lifetimes. Manufactured abrasives have both superior performance and consistency consequendy, they have largely replaced the natural ones. 

Increases in U.S. demand for caustic soda have been unpredictably high in the last few years. Between 1987 and 1989, the annual increase in demand was about 3% (6). However, the caustic soda market is mature and new areas of significant growth have not surfaced in recent years. The unexpected recent demand is generally related to two factors the pick-up in the U.S. economy after the slump of 1986 and pulp mills operating at fiiU capacity, leading to less efficient caustic use. 

Prices of natural products such as starch, which is produced ia many countries, and guar, which is produced mainly ia India and Pakistan, are affected by unpredictable factors such as the weather. Toward the end of 1991 prices were rising (93) however, ia the future an oversupply might cause a large drop ia prices. Because of the amounts used, starch is usually purchased locally, and pricing fluctuates with local farm prices and conditions. 

Siace the mid-1980s, contaminated storm mnoff has become an object of increasing concern within iadustrial complexes. Storm flow is intermittent and unpredictable ia aature, and tittle data has been collected to typify its characteristics. The level of flow and degree of contamination not only varies within an iastallation it has its own geometric characteristics, which influence patterns of surface mnoff. 

As the temperature of the sliding interface increases, the coefficient of friction varies. This variation is unpredictable, and there exists no general trend except that at extremely high temperatures the coefficient may become very low (<0.15). This temporary loss in friction is referred to as fade (25). 

The term glass has two meanings, ie, the material and a state of matter. The glassy or vitreous condition is where the atoms of the material have a random orientation. This amorphous or noncrystalline nature leads to physical properties typical of the product caHed glass, including unpredictable breaks, no sharp melting temperature, and no heat of fusion. 

Uninhibited chloroprene suitable for polymerisation must be stored at low temperature (<10° C) under nitrogen if quaUty is to be maintained. Otherwise, dimers or oxidation products are formed and polymerisation activity is unpredictable. Insoluble, autocatalytic "popcorn" polymer can also be formed at ambient or higher temperature without adequate inhibition. For longer term storage, inhibition is required. Phenothiasine [92-84-2] / fZ-butylcatechol [2743-78-17, picric acid [88-89-17, and the ammonium salt of /V-nitroso-/V-pheny1hydroxy1 amine [135-20-6] have been recommended. 

Clinical studies with Norplant attest to its high contraceptive efficacy and safety. The main reason patients request the removal of Norplant is unpredictable vaginal bleeding episodes followed by amenorrhea. The bleeding problem is an unavoidable sequela of progestogen-only contraception. 

Inflationary Effects. Inflation can have a significant effect on the profitabiUty of a venture. However, the U.S. federal tax laws do not allow for indexing the inflationary effects on depreciation schedules, salvage values, replacement costs, or taxable income. Inflation rates can vary unpredictably with time and can differ for certain revenues of expenditures. 

Gross errors. These result from unpredictable... 

Unpredictable. Disks and plates tend to wobble, while fuller bluff bodies tend to rotate. 

When a liquid or solid substance is emitted to the air as particulate matter, its properties and effects may be changed. As a substance is broken up into smaller and smaller particles, more of its surface area is exposed to the air. Under these circumstances, the substance, whatever its chemical composition, tends to combine physically or chemically with other particles or gases in the atmosphere. The resulting combinations are frequently unpredictable. Very small aerosol particles (from 0.001 to 0.1 Im) can act as condensation nuclei to facilitate the condensation of water vapor, thus promoting the formation of fog and ground mist. Particles less than 2 or 3 [Lm in size (about half by weight of the particles suspended in urban air) can penetrate the mucous membrane and attract and convey harmful chemicals such as sulfur dioxide. In order to address the special concerns related to the effects of very fine, iuhalable particulates, EPA replaced its ambient air standards for total suspended particulates (TSP) with standards for particlute matter less than 10 [Lm in size (PM, ). 

Locations. Locations of defects of this type are essentially unpredictable but can occur wherever laminated metal is welded. 

Joly observed elevated "Ra activities in deep-sea sediments that he attributed to water column scavenging and removal processes. This hypothesis was later challenged with the hrst seawater °Th measurements (parent of "Ra), and these new results conhrmed that radium was instead actively migrating across the marine sediment-water interface. This seabed source stimulated much activity to use radium as a tracer for ocean circulation. Unfortunately, the utility of Ra as a deep ocean circulation tracer never came to full fruition as biological cycling has been repeatedly shown to have a strong and unpredictable effect on the vertical distribution of this isotope. 

MeOH, LaCl3, (MeO)3CH, 25°, 10 min, 80-100% yield/ Dimethyl acetals can be prepared efficlenlly under neutral conditions by catalysis with lanthanoid halides, but the results of the reaction with ketones are unpredictable. 

Decrements in vigilance (i.e., ability to detect small changes in one s environment that occur at unpredictable times) decreased exercise performance in both healthy persons and those with chronic obstructive pulmonary disease... 

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