Life test operational

Fig. 12.17 PBI/PTFE-ca/ H3PO4 based MEA 50 h single cell life test operated at 150 °C under a constant cunruit density of 700 mA cm. The cell was operated intermittently for periods of 10 h day . Thickness of membrane ... 

The battery system has reached more than 1700 cycles in life cycle tests. The calendar life of the /zebra battery has been proven to be close to five years in a continuing life test. In practical operation in cars the ZEBRA battery exceeded 110000 km within a three year period. This excellent result proves the ZEBRA battery to be a reliable system. 

We wish to test a new type of ceramic tube to the AljOg tube normally used to fabricate high-pressure sodium lamps in order to eompare lamp qualities and life-time operation. Select a method which would produce the desired results and describe how this would be accomplished. Note that the ceramic tube requires both strength and a high melting point. 

An overall DMFC stack energy conversion efficiency of 35% was achieved over a range of stack operating conditions of 0.46-0.57 V per cell. An extended life test over llOOh on a five-cell stack made of identical cell components and stack configurations was also performed. 

Life tests have shown that all the chelate catalysts studied by us have only a limited operating life. Their life is restricted in some cases by direct chemical attack on the molecule, the central atom passing into solution as an ion. It depends very much on the nature of the central atom, degree of polymerization, and temperature. As shown in Fig. 23, acid attack is strongest in the case of polymeric FePc on soot... 

Life testing conducted on N0 SPE sensor cells showed a 1 /day increase in signal over the first 20 to 30 days followed by a leveling in performance. Typical initial sensor response for the NO sensor cell is 3 /ppm N0. With daily- calibrations, high accuracy levels can be maintained throughout sensor life. For example, a prototype N0 detection instrument has operated for one year with the response to N0-in-air within 15 of the original calibration value. 

Tests on Cable Constructions. The Association of Edison Illumination Companies (AEIC) has approved an accelerated cable life test in which typical underground distribution power cables can be statistically compared based on their resistance to water treeing (number of days to fail). The comparison can be made by varying the type of insulation and/or other cable layers in an environment that contains hot water (90°C) under 8 V//x (200 V/mil) voltage stresses (four times the typical power cables operating voltages). 

Period 4 was a test of a very mild condition after a weekend shutdown. Period 7 was a test of the liquid feed pump at a low rate. Period 8 was a brief test for decline in activity from period 2, although the entire operation was too short for significant life testing. Periods in the order of 2,1,3,5, and 6 were intended to cover the desired range of increasing upgrading. 

The yield for fully functioning 120-stage shift registers, with a total of 2160 TFTs, is approximately 30%, which is in line with the increment in area compared with the 32-stage shift registers. Extensive operational life tests will be performed in the near future. 

Long-term Tests of Operating Display Panels. Life tests were being carried out at room temperature and at 80 °C to study the long-term stability of unshielded devices in contact with GH LC. The devices have been tested for over 1 year without visible degradation. 

In some earlier life tests performed by Wilson and co-workers, PEFCs utilizing thin-film platinum catalyst layers typically experienced a gradual performance loss over the first 500 to 1000 h of operation and then stabilized at about 70% of the original performance (here, performance is described in terms of the current density measured at 0.50 V, i.e., close to the maximum power output of the cell). In such life tests. 

However, with more stringent guidelines and since Whitestone was discharging Its waste after treatment directly to a stream, it was decided to install an RO system on the final aeration pond. A pilot test of approximately 1000 hours showed the usefulness of reverse osmosis and allowed Osmonics to specify the membrane elements and system layout with sufficient certainty to guarantee a reasonable life and operating characteristics to Whitestone. 

Two features that make separative work cost estimates very uncertain are uncertainty about laser energy efficiencies and ignorance of operating and maintenance costs, which can be obtained only by completing the development and making life tests on plant equipment. 

Wang Rong-hua, et al. 2002. The Failure Rate Function of W eibull Distribution in Progressive Stress Life Testing for the TFR, TRV and CE Models, Operations Research and Management Science. 11 47-55 (in Chinese). 

By the end of 1978, a small primary sodium leak was detected, which constrained the operation of the plant to about 22 MWth. In January 1982, another small sodium leak was detected in the nitrogen system (surrounding the primary vessel). The exact localization of the leak was estimated to be too long, too costly and too uncertain. Moreover, RAPSODIE had fulfilled its aims, it was then decided to finally shut down the reactor on 13 October 1982 after several end of life tests from May to October. The beginning of the first operations of the final shutdown started in April 1983. CEA was leader project in decommissioning of RAPSODIE reactor. 

In most reported fuel cell life tests, single cells or stacks were operated under steady-state conditions, because these conditions were most easily applied but, for many applications, unsteady conditions are more appropriate. 

The life test under normal operating conditions provides the most relevant PEM lifetime data, although this method is time-consuming and presents some difficulties in data analysis. 

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