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Spontaneous probability

Boron reacts with sulfur at 600°C becoming incandescent [1]. Mixtures of sulfur with lamp black or freshly calcined charcoal ignite spontaneously, probably owing to adsorbed oxygen on the catalytic surface [2], Mixtures of yellow phosphorus and sulfur ignite and/or explode on heating [3], Ignition of an intimate mixture of red phosphorus and sulfur causes a violent exothermic reaction [4],... [Pg.1902]

A form of salt loss in infancy was long considered to be due to renal tubules that were refractory to aldosterone. Recent studies have described variant roots of the condition, either mutations in the mineralocorticoid receptor, the genes coding the epithelial sodium channel (ENaC), or other causes [6]. Many infant patients recover spontaneously, probably due to maturation of proximal tubular function. [Pg.591]

OHS convenanten. Another relevant development in OHS regulation in the Netherlands was the announcement in early 1999 of the Secretary of State s intention to conclude so-called OHS convenanten arboconvenanten) with a number of sectors of industry and public services. They aimed to reduce populations at risk that is, those exposed to prioritised occupational haz ds. The government initially selected 29 high-risk sectors, but additionally, other sectors apphed spontaneously (probably stimulated by the subsidies the government made available for the drafting md implementation of OHS convenanten). [Pg.301]

Glutathione-mediated disulphide reductions whether enzyme mediated or spontaneous probably proceed through an intermediate mixed disulphide via a thiolate displacement mechanism. [Pg.318]

An excited molecular level Ei) is connected with three lower levels n) and the groimdstate 0> by radiative transitions with spontaneous probabilities... [Pg.59]

Self-assembled monolayers (SAMs) are molecular layers tliat fonn spontaneously upon adsorjDtion by immersing a substrate into a dilute solution of tire surface-active material in an organic solvent [115]. This is probably tire most comprehensive definition and includes compounds tliat adsorb spontaneously but are neither specifically bonded to tire substrate nor have intennolecular interactions which force tire molecules to organize tliemselves in tire sense tliat a defined orientation is adopted. Some polymers, for example, belong to tliis class. They might be attached to tire substrate via weak van der Waals interactions only. [Pg.2620]

The light emitted in the spontaneous recombination process can leave tire semiconductor, be absorbed or cause additional transitions by stimulating electrons in tire CB to make a transition to tire VB. In tliis stimulated recombination process anotlier photon is emitted. The rate of stimulated emission is governed by a detailed balance between absorjDtion, and spontaneous and stimulated emission rates. Stimulated emission occurs when tire probability of a photon causing a transition of an electron from tire CB to VB witli tire emission of anotlier photon is greater tlian that for tire upward transition of an electron from tire VB to tire CB upon absorjDtion of tire photon. These rates are commonly described in tenns of Einstein s H and 5 coefficients [8, 43]. For semiconductors, tliere is a simple condition describing tire carrier density necessary for stimulated emission, or lasing. This carrier density is known as... [Pg.2894]

The "zip-reaction (U. Kramer, 1978, 1979) leads to giant macrocycles. Potassium 3- ami-nopropyl)amide = KAPA ( superbase ) in 1,3-diaminopropane is used to deprotonate amines. The amide anions are highly nucleophilic and may, for example, be used to transam-idate carboxylic amides. If N- 39-atnino-4,8,12,16,20,24,28,32,36-nonaazanonatriacontyl)do-decanolactam is treated with KAPA, the amino groups may be deprotonated and react with the macrocyclic lactam. The most probable reaction is the intramolecular formation of the six-membered ring intermediate indicated below. This intermediate opens spontaneously to produce the azalactam with seventeen atoms in the cycle. This reaction is repeated nine times in the presence of excess KAPA, and the 53-membered macrocycle is formed in reasonable yield. [Pg.249]

A different reaction takes place between an ethereal solution of the disulfide and hydrogen azide this reaction proceeds according to Eq. (15). Probably the principal step of this reaction is the spontaneous decomposition of the disulfide into nitrogen, sulfur, and... [Pg.275]

Other reasons for a wide propagation of polymerization in water include (1) reduction of energy consumed to separate the initial monomer in crystal form (acrylamide is produced and used in the aqueous solution form), which, in addition, is associated with the probability of its spontaneous polymerization, and (2) recovery of the organic solvents, which results in less environmental pollution and the elimination of the stage of solution of polymer reagents used, as a rule, in the form of the aqueous solutions. [Pg.65]


See other pages where Spontaneous probability is mentioned: [Pg.250]    [Pg.250]    [Pg.81]    [Pg.294]    [Pg.508]    [Pg.57]    [Pg.43]    [Pg.72]    [Pg.54]    [Pg.55]    [Pg.77]    [Pg.250]    [Pg.250]    [Pg.81]    [Pg.294]    [Pg.508]    [Pg.57]    [Pg.43]    [Pg.72]    [Pg.54]    [Pg.55]    [Pg.77]    [Pg.309]    [Pg.1552]    [Pg.2467]    [Pg.2479]    [Pg.2486]    [Pg.2820]    [Pg.2857]    [Pg.18]    [Pg.284]    [Pg.129]    [Pg.16]    [Pg.361]    [Pg.118]    [Pg.103]    [Pg.1418]    [Pg.283]    [Pg.13]    [Pg.437]    [Pg.230]    [Pg.510]    [Pg.127]    [Pg.1262]    [Pg.191]    [Pg.59]    [Pg.344]    [Pg.548]    [Pg.534]   
See also in sourсe #XX -- [ Pg.521 ]




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