Barrier Block

A physical barrier blocking direct electron transfer... 

It is important to note that the appearance of a single oxidation process for PVF indicates that there is no interaction between the ferrocene subunits in the polymer chain, which means that the carbon chain creates a barrier blocking the electronic communication between the ferrocenyl groups. 

Dike— An embankment of earth or rock built to act as a barrier blocking passage of material to surrounding areas. 

Numerous technical, business practice, and regulatory barriers block distributed generation projects from being developed. 

While a permit or license—figuratively speaking—lifts a barrier blocking a thoroughfare, the dispensation or exemption from a ban just gives a person the right to climb over a fence. 

In this case, the following four barriers block the path for radioactivity release into the environment fuel matrix fuel element cladding solidified lead, and a capsule vessel. The solidified lead that contacts the fuel element claddings made of steel eliminates any kind of corrosion. 

In order make the analysis, two trials of the field tests performed by HSL (Butler Royle, 2001) were chosen the former presenting an unobstructed scenario and the second with a barrier blocking the spread of the cloud. 

Although the concentrations of acetic acid in oil-field brines cannot be in equilibrium with both CO2 and CH4, they may be in redox equilibrium with CO2 as demonstrated by additional calculations described in this chapter. This means that there is an enormous kinetic barrier blocking reactions between acetic acid and CH4 under sedimentary basin conditions. Therefore, acetic acid is preserved in a metastable state in oil-field brines, and appears to be in metastable equilibrium with CO2. 

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