Reverse breakdown

The coefficient Tj is termed the modulus of rigidity. The viscosities of thixotropic fluids fall with time when subjected to a constant rate of strain, but recover upon standing. This behavior is associated with the reversible breakdown of stmctures within the fluid which are gradually reestabflshed upon cessation of shear. The smooth sprea ding of paint following the intense shear of a bmsh or spray is an example of thixotropic behavior. When viscosity rises with time at constant rate of strain, the fluid is termed rheopectic. This behavior is much less common but is found in some clay suspensions, gypsum suspensions, and certain sols. 

Examples of reversible breakdown of structure have been reported for procaine penicillin dispersions (7), for model systems of calcium carbonate in polybutene ( ), and for numerous other systems. During shear the particles are forced into contact with each other with sufficient kinetic energy to overcome any natural barrier against their displacement of a lyosphere around each individual particle. A dispersion which is inherently stable can thus be forced by shear into a condition of instability. 

BV Diode reverse breakdown voltage. Used to set the diode breakdown voltage in rectifier diodes, and the Zener breakdown voltage in Zener diodes. volt oo... 

Expression of the therapeutic protein is enhanced by electroporation - the application of a small amount of electricity at the site of injection for a few milliseconds. This high-intensity electric field induces temporary and reversible breakdown of the plasma membrane allowing plasmids and other molecules to gain intracellular access [110]. This plasmid-based PA-inducible transgene regulating... 

Figure 6.14 Reverse breakdown for samples without and with SiN nanonetwork. Inset shows semi-log plot of sample with 3 min SiN nanonetwork. Reproduced from Xie JQ et al., Applied Physics Letters 89(15) Art. No. 152108. Copyright (2006), with permission from the American Institute of Physics...

Ref [8] shows the dependence of the reverse breakdown voltage of 6H-SiC and depletion width on the background carrier concentration measured in n-type layers. The dependence of the breakdown voltage on the carrier concentration is approximately linear on a log-log... 

Ghezzo et al [13] reported on ion implanted planar p-n junction 6H-SiC diodes fabricated by ion implantation of B into n-type SiC with the donor concentration of 9x 1015cm 3. The implantation was performed at 25 °C and 1000°C followed by a 1300°C post-implant furnace anneal. The diodes had an ideality factor of 1.77 at room temperature, the reverse leakage current of 1 O 10 A cm 2 at -10 V and the reverse breakdown voltage of -650 V. 

FIGURE 4 Measured dependence of the reverse breakdown voltage and maximum electric field on background... 

Thermally induced property loss in polyurethanes occurs by two mechanisms physical, or reversible, breakdown of the polymer network and degradation due to chemical, or irreversible, processes. Physical breakdown is more of a problem with linear, thermoplastic polyurethanes and is related to such problems as softening and creep at elevated temperatures. This can be overcome by incorporating chemical crosslinks into the polymer matrix. Irreversible thermal degradation is a much more serious problem. The thermal stability of these materials is dependent upon their method of preparation and, more importantly, upon the structure of the resulting polymer. Thermolysis usually occurs within the isocyanate-derived portions of the polymer. The order of stability of the various isocyanate-derived linkages most commonly found in polyurethanes is ... 

Reverse Breakdown Voltage Maximum reverse biased voltage that can be applied to the diode without it conducting electrical current, sometimes just called the breakdown voltage. 

Membranes with reversible breakdown are prone from the point of view of energetics to the formation of a large number of pores. Under the action of the field their number and average radius increases in time. Suitable molecular geometry of lipids probably makes a membrane reversible in its behavior. 

The particular ratio of concentration terms that we write for a given reaction is called the reaction quotient (Q, also known as the mass-action expression). For the reversible breakdown of N2O4 to NO2, the reaction quotient, which is based directly on the balanced equation, is... 

Shear Thinning Flow. Dispersions showing a decrease in viscosity with shear rate (or shear stress) are described as shear thinning or pseudoplastic. Shear thinning behavior is generally produced by the reversible breakdown of suspension structures or alignment of anisotropic particles due to shear. 

A Zener diode is a silicon junction diode but with a different characteristic than the semiconductor diode considered previously. It is a special diode with a predetermined reverse breakdown voltage, the mechanism for which was discovered by Carl Zener in 1934. Its symbol and general appearance are shown... 

Non-ideal diode behaviors (reverse leakage, series and shunt resistances, nonideal behavior, reverse breakdown) and the ideality factor. 

Reverse breakdown mechanisms (tunneling, impact ionization). 

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