Power conjugation

Bond graph methodology assumes that the current amount of power P t) at time instant f > 0 transferred between two power ports can be expressed equally in all energy domains as the product of two power conjugated variables called effort, e, and ow, f, respectively. 

The Cu(I) catalyzed azide/alkyne Huisgen 1,3-dipolar cycloaddition is a very powerful conjugation reaction for surface modification of liposomes. The... 

Modem scaling theory is a quite powerful theoretical tool (appHcable to Hquid crystals, magnets, etc) that has been well estabUshed for several decades and has proven to be particularly useful for multiphase microemulsion systems (46). It describes not just iuterfacial tensions, but virtually any thermodynamic or physical property of a microemulsion system that is reasonably close to a critical poiat. For example, the compositions of a microemulsion and its conjugate phase are described by equations of the foUowiug form ... 

Table 4-1 lists some rate constants for acid-base reactions. A very simple yet powerful generalization can be made For normal acids, proton transfer in the thermodynamically favored direction is diffusion controlled. Normal acids are predominantly oxygen and nitrogen acids carbon acids do not fit this pattern. The thermodynamicEilly favored direction is that in which the conventionally written equilibrium constant is greater than unity this is readily established from the pK of the conjugate acid. Approximate values of rate constants in both directions can thus be estimated by assuming a typical diffusion-limited value in the favored direction (most reasonably by inspection of experimental results for closely related... 

These rate constants are for the hydrolysis of cinnamic anhydride in carbonate buffer, pH 8.45, total buffer concentration 0.024 M, in the presence of the catalysts pyridine, A -methylimidazole (NMIM), or 4-dimethylaminopyridine (DMAP). In the absence of added catalyst, but the presence of buffer, the rate constant was 0.005 24 s . You may assume that only the conjugate base form of each catalyst is catalytically effective. Calculate the catalytic rate constant for the three catalysts. What is the catalytic power of NMIM and of DMAP relative to pyridine ... 

The UV spectra of —I—M 2-substituted thiophenes show two almost overlapping high-intensity bands both of which are displaced, with increasing conjugating power of the substituent, toward longer wavelengths. The extinction increases in the same order as in the... 

The —I—M 3-substituted thiophenes in alcohol show only one band, and, as is found in the 2-isomer, this is displaced (with increased extinction) toward longer wavelength with increasing conjugating power of the substituent. It is probable that this is the displaced 235-m/A band of thiophene, since the spectra of 3-acetylthio-phene and 3-cyanothiophene also show a primary band at about 225 mju, in hexane solution. ... 

Reduction of "Me- CuLi2" wiiii LAH was described by Asliby and crr-workers as a o produce tlie powerful reducing reagent "Li2CuH- " [10], wbidi can be n temperature for conjugate reductions lEq. 5.3). 

The 1,4-addition of an enolate anion 1 to an o ,/3-unsaturated carbonyl compound 2, to yield a 1,5-dicarbonyl compound 3, is a powerful method for the formation of carbon-carbon bonds, and is called the Michael reaction or Michael addition The 1,4-addition to an o ,/3-unsaturated carbonyl substrate is also called a conjugate addition. Various other 1,4-additions are known, and sometimes referred to as Michael-like additions. 

In low-dimensional systems, such as quantum-confined. semiconductors and conjugated polymers, the first step of optical absorption is the creation of bound electron-hole pairs, known as excitons [34). Charge photogcncration (CPG) occurs when excitons break into positive and negative carriers. This process is of essential importance both for the understanding of the fundamental physics of these materials and for applications in photovoltaic devices and photodctcctors. Since exciton dissociation can be affected by an external electric field, field-induced spectroscopy is a powerful tool for studying CPG. 

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