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991.
An innovative technology for industrial wastewater treatment has been developed. The main focus of the new system is a transformation of persistent organic compounds (biorecalcitrant COD) into a biodegradable fraction, followed by high efficient biological elimination using specialised bacteria's. To fulfill these targets the Aqua-Biomant process integrates two treatment steps: an aerated biological upflow filter and a electrochemical oxidation technique using boron doped-diamond electrodes. The advantages of the process are high efficient COD removal with reduced energy consumption combined with low total residence time. 相似文献
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993.
The IGES Model Comparison System (IMCOS) is the first test tool to allow an easy and automatic semantic comparison of CAD models represented in IGES format. By systematically analyzing and comparing entity data and structures of generated and exchanged IGES models, it detects loss of information and functionality resulting from model exchange via IGES processors. IMCOS was designed and implemented as a tabledriven IGES processor to allow external control of the comparison process and full coverage of the current version of IGES (Version 3.0) and future versions. This article presents the basic concepts of IMCOS. The great interest in and discussion of IMCOS have shown the importance of such a test tool. IMCOS may be used as one of several test tools within an overall IGES verification program. 相似文献
994.
P. Runow 《International Journal of Pressure Vessels and Piping》1985,21(3):157-207
Since it is an integral method permitting continuous monitoring and remote defect location, acoustic emission offers promising benefits for the nuclear industry. Particular potential applications relating to the integrity of the primary pressure boundary of nuclear reactors that are considered in this report are the detection of flaws during pre-service and requalification hydrotests, and continuous monitoring for crack growth and leakage.The correlations between fracture mechanics and acoustic emission are discussed on the basis of certain fundamentals of material emission behaviour. The influence of instrumentation and of aspects related to wave propagation on the detectability and evaluation of acoustic emission signals is considered.The conclusion reached is that at the present time acoustic emission can be used predominantly during hydrotests as a search method for cracks. Although some degree of characterization and sizing of defects may be obtained on the basis of empirical data, a quantitative evaluation of defect severity based on fracture mechanics cannot yet be made satisfactorily. It is expected that a considerable improvement in this respect may be achieved by applying a transfer correction that takes into account the depth position and directivity pattern of the source.The technique of leak detection by acoustic emission shows promising results permitting the location and quantification of leaks. Practical experience and future research work are expected to enhance the accuracy and detection sensitivity. 相似文献
995.
A calorimetric measurement technique developed for NASA's Deep Space Network (DSN) transmitters that does not require data on the coolant's thermal parameters is described. Calibration of the measurement system is achieved by measuring the DC input power to the klystron and relating coolant temperature increase to this known power dissipation. Agreement between calorimetric and electrical measurements of total system power was good, the difference being less than 2%. The operation of the system was not greatly affected by the composition of the coolant, which was varied from pure water to 40% ethylene glycol by mass. Good accuracy was also shown at output power levels, which varied over a 3.6:1 range 相似文献
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With the aim of optimizing the performance of Li/Li1+xV3O8 cells, several aspects of cathode preparation have been examined. The influence of synthesis technique, nature and amount of conductive additives, compacting pressure, cathode loading, and particle size, has been investigated. Furthermore, the role played by the solutions on cathode efficiency has been outlined. The formulations which perform best are based on small-sized particles blended with about 20% acetylene black and compacted at very high pressures to improve the contact between particles. Such cathodes can provide high capacities at high rates and good cycling efficiencies. The kinetic loss of capacity, observed during the first few cycles, may be alleviated by choosing solutions with high fluidity and conductivity. 相似文献
1000.
Salmonella strains exposed to lethal doses of gamma radiation are detoxified but retain their antigenic properties. Using eight Salmonella strains representative of each of the Salmonella serogroups A to G, a polyvalent radiovaccine has been developed which effectively immunizes mice to several Salmonella serotypes. 相似文献