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Nutrient recovery and biodegradation of inedible biomass is an integral part of an Advanced Life Support (ALS) system for space travel. This study investigates the mineralization and nitrogen recovery of hydroponically grown crops, namely, tomato, peanut, wheat and a 50:50 mixture of peanut and wheat. Shaker flask studies were conducted under various growth conditions of temperature and incubation times utilizing activated sludge and Phanerochaete chrysosporium (P. chrysosporium) inocula. Incubation temperature ranged from 25°C to 60°C and the flasks were monitored for nutrient recovery and solids reduction at 16, 32, 64 and 128 days. For the activated sludge systems, overall solids destruction during the 128 days of incubation ranged from 56% to 60% for the crops investigated. Similar results were found for the fungal systems indicating no substantial degradation enhancement.

Micronutrient recovery was investigated in two microbial systems, activated sludge and Phanerochaete chrysosporium (P. chrysosporium). Hydroponically grown crops, namely, tomato, peanut, wheat and a 50:50 mixture of peanut and wheat were used in the study. The experiments were conducted in shaker flasks on a 1% solids basis at 25°C for all crops and at 25°C, 40°C, 50°C and 60°C for tomato plant material. The micronutrient content of the leachate was determined initially and after 16, 32, 64, and 128 days of incubation. In order to determine the extent and rate of micronutrient release during the initial stages of incubation, when most of the solids degradation occurs, two separate experiments were conducted in batch reactors for 16 days. The micronutrient content of the batch reactor leachate was monitored on a daily basis. Micronutrients assessed included boron, manganese, iron, magnesium, zinc, copper, calcium, phosphorus and potassium.

The operational life and reliability of internal combustion (I.C.) engines are limited by the breakdown of the engine components due to wear under boundary lubricated conditions. It is very advantageous to know the condition of an engine and its components without disassembling the engine for examination. This paper employs the chemical and physical analysis of used synthetic crankcase oil to predict the condition of the lubricant and engine wear components during continuous operation. In this research, it is concluded that the iron content of the used oil can be used to define the oil drain interval to optimize oil use in the engine and minimize the wear process. Using an engine dynamometer, the optimum oil drain interval for a fully synthetic 15W50 was found to be 11,000 km.