Electrochemical Cell Gas Detector

SAMPE 2011 Long Beach Product Showcase

The annual Society for the Advancement of Material and Process Engineering’s (SAMPE) Convention & Exhibition returned, for the first time since 2008, to its long-time base in Long Beach, Calif., after a first-ever Pacific Northwest showing last year in Seattle, Wash. The four-day event, held May 23-26 at the Long Beach Convention Center, met with considerable success. The SAMPE 2011 exhibit hall was sold out this year, with 356 exhibitors (including 106 first-time exhibitors) representing 555 companies. Attendance figures indicated the show took a large leap; the official count topped 7,100, with delegates coming from 48 U.S. states, the District of Columbia and 27 other countries.

Organized by SAMPE’s Orange County Chapter, the SAMPE conference was cochaired by Joyce Lentz, president of National Aerospace Supply Co. (San Juan Capistrano, Calif.), and Darrell Reed, quality control engineer at OCM Test Labs (Anaheim, Calif.). Eight tutorials and more than 250 technical papers were presented by M&P practitioners and researchers.

"SAMPE is on an upward trend," commented Dr. Allan Crasto, associate director at UDRI (Dayton, Ohio) and sitting SAMPE international president. "We seem to have fully recovered from the impact of the recession.” On Tuesday, conference delegates attended a keynote presentation on “Understanding and Managing Risk in Human Space Flight Developments and Operations” by Dr. Mike Ryschkewitsch, chief engineer at NASA. He discussed NASA’s approach to certification of systems for human spaceflight.

Wednesday’s keynoter, Andreas Wüllner, managing director of SGL Automotive Carbon Fibers GmbH (Munich, Germany), filled in the background on the events that led to the much-publicized decision by the SGL/BMW joint venture to build its now nearly complete captive carbon fiber production plant in Moses Lake, Wash. Wüllner reported that the carbon fiber manufacturing facility is complete and that testing of the first production line will begin this summer, followed by the plant’s official opening sometime in third quarter 2011. In his presentation, “SGL Carbon Group – BMW: A Visionary Joint Venture for Carbon Fiber Composites in Automotive Applications,” he updated the audience on the development of the BMW all-electric i3 and hybrid electric i8 vehicles, both of which make use of resin transfer molded SGL carbon fiber composites in the passenger cell, called the Life Module. During the Q&A after his address, Wüllner was asked about repair of carbon fiber composites on the two car models in the event of damage. Wüllner said that BMW is establishing dedicated global repair facilities designed specifically to repair damaged composite structures. He would not say, however, whether body panels (hood, roof, door panels, etc.) on the i3 and i8 would be made of composites.

Fire & Gas Monitoring Systems: Gas Detectors & Commonly used ...

A gas detector is a device which detects the presence of various gases within an area, usually as part of a safety system. This type of equipment is used to detect a gas leak and interface with a control system so a process can be automatically shut down. A gas detector can also sound an alarm to operators in the area where the leak is occurring, giving them the opportunity to leave the area. This type of device is important because there are many gases that can be harmful to organic life, such as humans or animals. The catalytic bead sensor consist of two coils of fine platinum wire each embedded in a bead of alumina, connected electrically in a bridge circuit. One of the pellistors is impregnated with a special catalyst which promotes oxidation whilst the other is treated to inhibit oxidation. Current is passed through the coils so that they reach a temperature at which oxidation of a gas readily occurs at the catalysed bead . Passing combustible gas raises the temperature further which increases the resistance of the platinum coil in the catalysed bead, leading to an imbalance of the bridge. This output change is linear, for most gases, up to and beyond 100% LEl, response time is a few seconds to detect alarm levels (around 20% LEL) This is a type of cell  that instead of being designed to produce power, is designed to produce a current that is precisely related to the amount of the target gas in the atmosphere. Measurement of the current gives a measure of the concentration of gas in the atmosphere. Essentially the electrochemical cell consists of a container, 2 electrodes, connection wires and an electrolyte - typically sulfuric acid. Carbon monoxide is oxidized at one electrode to carbon dioxide while oxygen is consumed at the other electrode. For carbon monoxide detection, the electrochemical cell has advantages over other technologies in that it has a highly accurate and linear output to carbon monoxide concentration, requires minimal power as it is operated at room temperature, and has a long lifetime (typically commercial available cells now have lifetimes of 5 years or greater). Thin wires of the tindioxide on an insulating ceramic base provide a sensor monitored by an integrated circuit. This sensing element needs to be heated to approximately 400 deg C in order to operate.

Semiconductor industrial hygiene handbook, monitoring, ventilation, equipment, and ergonomics

Emissions reduction, NOx/SOx suppression

Analytical instrumentation

Semiconductor safety handbook, safety and health in the semiconductor industry

Forensic and environmental detection of explosives