Analogy conduction

The C-C linkage in tire polymeric [60]fullerene composite is highly unstable and, in turn, tire reversible [2+2] phototransfonnation leads to an almost quantitative recovery of tire crystalline fullerene. In contrast tire similarly conducted illumination of [70]fullerene films results in an irreversible and randomly occurring photodimerization. The important aspect which underlines tire markedly different reactivity of tire [60]fullerene polymer material relative to, for example, tire analogous [36]fullerene composites, is tire reversible transfomration of tire fomrer back to the initial fee phase. 

An expression for the current across a molecular junction is developed by analogy with the description of unimolecular solution phase electron transfer. The conduction is written 1201... 

On a curved surface the virtual conductivity is found analogously as... 

Oxindoles can be prepared from Af,p-acylphenylhydrazines by a reaction which is analogous to the Fischer cyclization. This is known as the Brunner reaction. The reaction is typically conducted under strongly basic conditions. For example, heating Af-phenylcyclopentanecarbonylhydrazide with CaO gives a 70% yield of spiro-cyclopentane oxindole[l]. 

Another attractive commercial route to MEK is via direct oxidation of / -butenes (34—39) in a reaction analogous to the Wacker-Hoechst process for acetaldehyde production via ethylene oxidation. In the Wacker-Hoechst process the oxidation of olefins is conducted in an aqueous solution containing palladium and copper chlorides. However, unlike acetaldehyde production, / -butene oxidation has not proved commercially successflil because chlorinated butanones and butyraldehyde by-products form which both reduce yields and compHcate product purification, and also because titanium-lined equipment is required to withstand chloride corrosion. 

An analogy exists between mass transfer by diffusion and heat transfer by conduction. Each involves coHisions between molecules and a gradient as the driving force which causes flow. Eor diffusion, this is a concentration gradient for conduction, the driving force is an energy gradient. Eourier s... 

By analogy with the tlrermal conduction equation for a gas, given by the kinetic theoty of gases, we can write for tire thermal conductivity, K, of a solid... 

The first elaboration of crowns deliberately into sulfur-containing analogs seems to have been conducted by Pedersen . The first of these efforts was directed at incorporating sulfur in complexes of macrocyclic polyethers. Inclusion of sulfur as a portion of ring system 5 was also accomplished as shown in Eq. (6.4) and is reported in a patent which issued before the latter, but was actually filed after it. We note... 

The example shown in Eq. (6.5) was conducted using 0.5 mole of bis-(2-mer-captoethyl) ether and 0.5 mole of 1,8-dichloro-3,6-dioxaoctane. The base was sodium hydroxide (1 mole) and between 900 and 2,000 mL of ethanol were used. The exact quantity of ethanol used in this synthesis is not clear from the experimental description. The reaction time was somewhere between 7 and 14 hours (again, unspecified), after which time the product (6) was isolated by vacuum distillation, as a viscous oil, in 27% yield. Similar approaches were utilized by this group for the synthesis of other analogs ". ... 

Conduction takes place at a solid, liquid, or vapor boundary through the collisions of molecules, without mass transfer taking place. The process of heat conduction is analogous to that of electrical conduction, and similar concepts and calculation methods apply. The thermal conductivity of matter is a physical property and is its ability to conduct heat. Thermal conduction is a function of both the temperature and the properties of the material. The system is often considered as being homogeneous, and the thermal conductivity is considered constant. Thermal conductivity, A, W m, is defined using Fourier s law. 

Pick s law States that the molecular diffusion of water vapor in a gas without appreciable displacement of the gas is analogous to the conduction of heat, and is governed by a similar type of law. 

High-temperature reduction of Na2Ti03 with hydrogen produces nonstoichiometric materials, Na jTi02 (jr = 0.20-0.25), called titanium bronzes by analogy with the better-known tungsten bronzes (p. 1016). They have a blue-black, metallic appearance with high electrical conductivity and are chemically inert (even hydrofluoric acid does not attack them). 

When methylene chloride was used as a solvent, it was found that 28 are obtained in minor amounts, while the dominating product is the -coordinated chloro-carbyne species [(> -Tp )Mo(CO)2(=CCl)], whose yield increases abruptly with substitution in the pyrazol-l-yl fragments (3-methyl-, 3,4,5-trimethyl-, and 3,5-dimethyl-4-chloro derivatives) [90AX(C)59,95JCS(D) 1709]. The tungsten analog can be prepared similarly. The chlorocarbyne molybdenum complex follows also from the reaction of the parent anion with triphenylsulfonium cation but conducted in dichloromethane. The bromo- and iodocarbyne derivatives are made similarly. 

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