Leakage channels

Hodgkin and Huxley [81] formulated a membrane model that accounts for K" ", Na" ", and ion leakage channels in squid giant axons [Fig. 22(a)]. The membrane resting potential for each ion species is treated like a battery and the degree to which the channel is open is modeled by a variable resistor. 

The classification of ion channels by their topology is exemplified for potassium channels in Figure 8.1 [1], Potassium channels can be classified into 2TM/P channels, which contain two transmembrane helices (TM) with one P loop (P) between them, 6TM/P channels, 7TM/P channels, 8TM/2P channels, and 4TM/2P channels. The 4TM/2P family is called leakage channels and is targeted by numerous anesthetics [8],... 

Compression set is one of the most widely measured properties of rubber, featuring in a range of material and product specifications and finding use as a sensitive measure of the state of cure in both conventional thermoset rubbers and newer dynamically vulcanized thermoplastic rubbers. Comparative ease of determination has made compression set a popular test for sealing applications, although it is increasingly accepted that the property should not be used in place of the often more relevant stress relaxation. However, it can be relevant to seals where sufficient bodily movement occurs to open up a leakage channel before recovery of shape can take place. 

Squid axon Hodgkin and Huxley Most models of excitable cells are descendents of this model. The basic circuit equivalent of this model comprises a linear capacitance in parallel with three resistor-battery subcircuits (one each for sodium, potassium, and a nonspecific leakage channel). The HHequations in their original form were ... 

First point seal the coal, isolation of oxygen, plugging leakage channel and fracture of coal body. 

Li, Y.C. Zhang, S.Q. Zhang, S. 2013. The qualitative identification of air leakage channels in goaf based on the tracer gases. Safety in Coal Mines 44(1) 185-188. 

Spiral baffles, which are sometimes installed for hquid services to improve heat transfer and prevent channeling, can be designed to serve as reinforcements. A spiral-wound channel welded to the vessel wall is an alternative to the spiral baffle which is more predictable in performance, since cross-baffle leakage is eliminated, and is reportedly lower in cost [Feichtinger, Chem. Eng., 67, 197 (Sept. 5, I960)]. 

For example, unsatisfactory equipment design has caused inlet-end erosion due to improper distribution of water in the water box. Poor design and construction practices have caused erosion-corrosion of the tube sheet due to unsatisfactory water distribution or leakage past pass partitions. Deep channels (wire drawing) or worm holes have been observed in tube holes due to leaking tube-to-tube sheet joints. 

General description. Burnthrough as discussed here specifically refers to the melting of tube metal in the vicinity of the weld such that a cavity is formed. If burnthrough is severe, a continuous channel may be produced that can cause leakage. 

As discussed in the previous section, it is convenient to consider the output from the extruder as consisting of three components - drag flow, pressure flow and leakage. The derivation of the equation for output assumes that in the metering zone the melt has a constant viscosity and its flow is isothermal in a wide shallow channel. These conditions are most likely to be approached in the metering zone. 

Ableiterohr, n. delivery tube or pipe. Ableitung,/. derivation derivative deduction carrying off drainage channel turm ng aside (Elec.) leakage, stray current, also grounding. 

Ritchie L.J., Ferguson C.P., Bessant C., Saini S., A ten channel fibre-optic device for distributed sensing of underground hydrocarbon leakage, J.Environ. Monitor. 2000 2 670-673. 

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