background: various chemicals are used to produce polymers ,leakage of polymer materials over the time , can cause health problems the aim of this research was to evaluate the leakage of heavy metals from the pvc and polypropylene pipes used in the water distribution system in isfahan. methods: four brands of pp pipes and two various types of pvc pipes were analyzed in this study. concentration...

Large-scale deployment of CO2 geological sequestration requires understanding and assessing the risks of such an operation. One of these risks is the potential contamination of groundwater by CO2/brine leakage into shallow aquifers. Although our understanding of this issue has improved significantly over the last decade, several questions still need to be better addressed, including the fate of...

A wear metal profile is often prepared for each engine. Typically an early wear-in period of high metals concentration is observed, followed by a plateau of low metals concentration [2]. Impending component failure will be indicated by a rapid increase in wear metal concentration, or the sudden appearance of a metal. The metal type and concentration may also indicate to the analyst and engineer...

To maintain function in biofilters over time and reduce risk for leakage of metals, regular maintenance, including replacement top layer is recommended. However, consider metal fractionation when handling material.

InAIAslInGaAs HFET’s fabricated by conventional mesa isolation have a potential parasitic gate-leakage path where the gate metallization overlaps the exposed channel edge at the mesa sidewall. We have unmistakably proven the existence of this path by fabricating special heterojunction diodes with different mesa-sidewall gate-metal overlap lengths. We find that sidewall leakage is a function of ...

Leakage current reduction is of primary importance as the technology scaling trends continue towards deep sub-micrometer regime. One of the leakage mechanisms which contribute significantly to power dissipation is the Gate Induced Drain Leakage (GIDL). GIDL sets an upper limit on the VLSI MOSFET scaling and may even lead to device breakdown. Thus, in order to improve performance, static power c...

In order to protect wiring, facilities, human bodies and the like from electric accidents such as overcurrent to the load, a short circuit, ground fault or earth leakage of an electrical line, low-voltage circuit breakers, as typifi ed by molded case circuit breakers (MCCB) and earth leakage circuit breakers (ELCB), are installed in every type of machine, equipment, facility and building that u...