Yield instantaneous

Careful reading of papers is required to determine which definition has been used. Measurements of the continuous phase resistance around bubbles frequently use photographic, volumetric, or pressure change techniques to yield instantaneous rates of mass transfer, and thus kA. Here too, both definitions of the Sherwood number, Eqs. (7-43) and (7-45), have been used. 

The reaction of 3-methyl-oxadiazole with mercuric chloride yields instantaneously a precipitate, which on prolonged standing in a buffered solution (pH 6.5) in the presence of an excess of HgClj yields a complex of a stable substitution product. 

Summarizing the discussions above, the necessary conditions for the preparation of ultrafine powders by reaction-precipitation may be concluded to be the following (1) Very fast reaction that can yield instantaneously a quantity of the substance to be precipitated (2) Very low solubility of the substance to be prepared in the form of ultrafine particles (3) Extremely high supersaturation and (4) Very uniform supersaturation. 

EXPERIMENTAL QUANTUM YIELD ( ) the number of observed events of a given phenomenon per photon absorbed by the system (see also Overall Quantum Yield, Instantaneous Quantum Yield, and Steady-State Quantum Yield). 

Benthic flux chamber experiments measure the loss or gain of various dissolved species from a fixed container on the seafloor, thus yielding instantaneous measurements of P cycling. A benthic flux chamber deployment in the Saanich Inlet in summer, 1997... 

For each configuration of the nuclei, minimization of tlie total energy with respect to the electron density yields the instantaneous value of a potential energy fiinction V(/ ), and the corresponding forces on the nuclei. In principle,... 

Commercially available photon tunneling microscopes have a lateral resolution of 160 nm but subnanometer vertical resolution. The nondestmctive, instantaneous 3-D viewing of a surface (no scanning) yields real-time imaging as one traverses a given sample. The sample must be a dielectric, but transparent polymer tepHcas of opaque samples can be studied. 

When a fiber is stressed, the instantaneous elongation that occurs is defined as instantaneous elastic deformation. The subsequent delayed additional elongation that occurs with increasing time is creep deformation. Upon stress removal, the instantaneous recovery that occurs is called instantaneous elastic recovery and is approximately equal to the instantaneous elastic deformation. If the subsequent creep recovery is 100%, ie, equal to the creep deformation, the specimen exhibits primary creep only and is thus completely elastic. In such a case, the specimen has probably not been extended beyond its yield point. If after loading and load removal, the specimen fails to recover to its original length, the portion of creep deformation that is recoverable is still called primary creep the portion that is nonrecoverable is called secondary creep. This nonrecoverable elongation is typically called permanent set. 

These effects can be attributed mainly to the inductive nature of the chlorine atoms, which reduces the electron density at position 4 and increases polarization of the 3,4-double bond. The dual reactivity of the chloropteridines has been further confirmed by the preparation of new adducts and substitution products. The addition reaction competes successfully, in a preparative sense, with the substitution reaction, if the latter is slowed down by a low temperature and a non-polar solvent. Compounds (12) and (13) react with dry ammonia in benzene at 5 °C to yield the 3,4-adducts (IS), which were shown by IR spectroscopy to contain little or none of the corresponding substitution product. The adducts decompose slowly in air and almost instantaneously in water or ethanol to give the original chloropteridine and ammonia. Certain other amines behave similarly, forming adducts which can be stored for a few days at -20 °C. Treatment of (12) and (13) in acetone with hydrogen sulfide or toluene-a-thiol gives adducts of the same type. 

Halogen-metal interconversion between bromothiophenes and n-butyllithium, leading to thienyllithium derivatives and n-butyl bromide, occurs almost instantaneously and in very high yield even at... 

For small enough temperature steps (< lOK) during small step annealing the vacancy concentration practically remains constant and corresponds to the instantaneous aimealing temperature. This allows for an easy analysis of SRO-kinetics yielding SRO-relaxation times and SRO-activation enthalpies, which by usual interpretation correspond to H +Hf. 

Whereas ductile materials, such as iron and mild steel, are often considered not to crack when charged with hydrogen and subjected to a tensile stress below the yield stress, the position is different with high-strength ferrous alloys where, depending on the strength of the steel and the hydrogen content, failure may occur well below the yield stress. However, the fracture process is not instantaneous and there is a time delay before cracks are... 

Crystalline triose reductone has been shown (56) by titration with strong base and with iodine, to exist in solution, for practical purposes, entirely as the enol form. In addition, the fact that it reduces exactly three molar equivalents of periodate to give quantitative yields of formic acid and of carbon dioxide indicates that it is also oxidized entirely in this form. However, nothing is known of the rate of enolization of tartronic dialdehyde and the possibility therefore remains that part of it may be oxidized in the dialdehydo form. If this were the case, the results of periodate oxidations would be dependent on the ratio of the rate of enolization of tartronic dialdehyde to the rate of its oxidation by periodate, since the oxidation of triose reductone is, again, for practical purposes, instantaneous. 

The addition of a cyclic vinyl sulfoxide anion to aldehydes has been reported only once14. Interestingly, 2,3,4,5-tetrahydro-l//-thiepane S-oxide cannot be metalated by lithium diiso-propylamide in tetrahydrofuran at — 78 °C. At higher temperatures ( — 20° to 0°) a white polymeric precipitate is formed. This polymeric product is also formed when the sulfoxide is treated with butyllithium or. wr-butyllithium in tetrahydrofuran even at — 78 C. However, metalation can be accomplished with. sec-butyllithium using an excess of N,N,N, N -tetramcthylethylenediamine in tetrahydrofuran at —78 C. In this case, a pale yellow solution is formed immediately and upon addition of benzaldehydc instantaneous dccolorization occurs yielding a mixture of diastereomeric alcohols in 90% yield. 

Likewise, the longer the duration of material stress or strain, the more time for viscous flow to occur. Finally, the greater the material stress or strain, the greater the likelihood of viscous flow and significant permanent deformation. For example, when a TP product is loaded or deformed beyond a certain point, the material comprising it yields and immediate or eventually fails. Conversely, as the temperature or the duration or magnitude of material stress or strain decreases, viscous flow becomes less likely and less significant as a contributor to the overall response of the material and the essentially instantaneous elastic deformation mechanism becomes predominant. 

Integration. A detector that yields discrete pulses can be used as an instantaneous detector if the pulses can be averaged to form a continuous electric current, as in a counting-rate meter. These devices usually consist of a capacitor that is charged by the pulses and a re-... 

A different approach consists of stepwise changing the adsorbent temperature and keeping it constant at each of the prefixed values Tx, Ts,. . ., Tn for a certain time interval (e.g. 10 sec), thereby yielding the so-called step desorption spectra s(81-85). The advantage of this method lies in a long interval (in terms of the flash desorption technique) for which the individual temperatures Ti are kept constant so that possible surface rearrangements can take place (81-83). Furthermore, an exact evaluation of the rate constant kd is amenable as well as a better resolution of superimposed peaks on a desorption curve (see Section VI). What is questionable is how closely an instantaneous change in the adsorbent temperature can be attained. This method has been rarely used as yet. 

Lewin and Cohen (1967) determined the products of dediazoniation of ben-zophenone-2-diazonium salt (10.42, Scheme 10-77) in five different aqueous systems (Table 10-7). About one-third of the yield is 2-hydroxybenzophenone (10.46) and two-thirds is fluorenone (10.45, run 1) copper has no effect (run 2). On the other hand, addition of cuprous oxide (run 3) has a striking effect on product ratio and rate. The reaction occurs practically instantaneously and yields predominantly fluorenone. As shown in Scheme 10-77, the authors propose that, after primary dediazoniation and electron transfer from Cu1 to 10.43 the sigma-complex radical 10.44 yields fluorenone by retro-electron-transfer to Cu11 and deprotonation. In the presence of the external hydrogen atom source dioxane (run 12) the reaction yields benzophenone cleanly (10.47) after hydrogen atom abstraction from dioxane by the radical 10.43. 

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